Diagnostic device, diagnostic method, and diagnostic program

Abstract

To make it possible to accurately diagnose the condition of a vibrating tube of a Coriolis mass flowmeter.SOLUTION: A diagnostic device (2) includes: a transmitting / receiving unit (200) that receives density calibration results regarding calibration of the density of fluid generated by calibrating a Coriolis mass flowmeter (1) that measures the flow rate and density of the fluid flowing through a vibrating tube (11) based on Coriolis force acting on the vibrating tube (11) that is vibrated; and a wall thickness and stiffness diagnostic unit (70) that executes calculations regarding at least one of the wall thickness and stiffness of the vibrating tube (11) based on the density calibration results and generates wall thickness and stiffness diagnostic results regarding changes in the vibrating tube (11).SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a diagnostic device, a diagnostic method, and a diagnostic program. [Background technology]

[0002] Coriolis mass flowmeters are known as one type of flowmeter used in plants. Coriolis mass flowmeters vibrate a vibrating tube (U-shaped tube) through which a fluid flows by exciting a coil, and measure the Coriolis force generated by the fluid passing inside the vibrating tube through the twisting of the vibrating tube. Since the Coriolis force increases according to the flow rate of the fluid, it is possible to measure the flow rate through the width and phase of the twisting of the vibrating tube.

[0003] In Coriolis mass flowmeters, the flow rate is measured by using the twisting of the vibrating tube, so if the vibrating tube becomes corroded, it will cause errors in the flow rate measurement. It is also desirable to know the corrosion of the vibrating tube for the maintenance of the tube. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4952820 [Patent Document 2] Patent No. 4469337 [Patent Document 3] Patent No. 4866423 [Patent Document 4] Patent No. 3523592 [Patent Document 5] Patent No. 7024466 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional techniques have room for improvement in terms of accurately diagnosing the condition of the vibrating tube of a Coriolis mass flowmeter. For example, in Patent Document 1, amplitude information is used to determine corrosion of the vibrating tube, which is affected by the amplification sensitivity of the driving circuit and the measurement circuit. In addition, in Patent Document 1, corrosion of the vibrating tube is determined based on rigidity, and the change in wall thickness is not directly obtained.

[0006] The present invention has been made in view of the above, and an object of the present invention is to accurately diagnose the condition of a vibrating tube of a Coriolis mass flowmeter. [Means for solving the problem]

[0007] The present invention provides a diagnostic device including: a transceiver unit that acquires a density calibration result related to calibration of the density of a fluid generated by calibrating a Coriolis mass flowmeter that measures the flow rate and density of a fluid flowing through a vibrating tube based on the Coriolis force acting on the vibrated vibrating tube; and a thickness and stiffness diagnostic unit that performs a calculation related to at least one of the thickness and stiffness of the vibrating tube based on the density calibration result and generates a thickness and stiffness diagnostic result related to a change in the vibrating tube.

[0008] The present invention also provides a diagnostic method in which a computer executes processing to acquire a density calibration result relating to calibration of the density of a fluid generated by calibrating a Coriolis mass flowmeter that measures the flow rate and density of a fluid flowing through a vibrating tube based on the Coriolis force acting on the vibrated vibrating tube, executes a calculation relating to at least one of the thickness and stiffness of the vibrating tube based on the density diagnostic result, and generates a thickness stiffness diagnostic result relating to a change in the vibrating tube.

[0009] The present invention also provides a diagnostic program that causes a computer to execute processing to acquire a density calibration result related to calibration of the density of a fluid generated by calibrating a Coriolis mass flowmeter that measures the flow rate and density of a fluid flowing through a vibrating tube based on the Coriolis force acting on the vibrated vibrating tube, perform a calculation related to at least one of the thickness and rigidity of the vibrating tube based on the density diagnosis result, and generate a thickness rigidity diagnosis result related to a change in the vibrating tube. Effect of the Invention

[0010] According to the present invention, it is possible to accurately diagnose the condition of the vibrating tube of a Coriolis mass flowmeter. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a diagnostic system according to an embodiment. [Diagram 2] 1 is a block diagram showing an example of the configuration of a Coriolis mass flowmeter according to an embodiment; [Diagram 3] FIG. 4 is a diagram illustrating an example of a measurement process of the Coriolis mass flowmeter according to the embodiment. [Figure 4] FIG. 2 is a block diagram showing an example of the configuration of each device of the diagnostic system according to the embodiment. [Diagram 5] FIG. 11 is a diagram showing an example of an entire density calibration process according to the embodiment. [Figure 6] FIG. 11 is a diagram illustrating an example of a density calibration process according to the embodiment. [Figure 7] FIG. 11 is a diagram illustrating an example of an overall density error diagnosis process according to the embodiment. [Figure 8] FIG. 2 is a diagram illustrating an example of density error diagnosis processing 1 according to the embodiment. [Figure 9] FIG. 11 is a diagram illustrating an example of density error diagnosis processing 2 according to the embodiment. [Figure 10] FIG. 11 is a diagram illustrating an example of density error diagnosis processing 3 according to the embodiment. [Figure 11] FIG. 11 is a diagram showing an example of an entire thickness stiffness diagnosis process according to the embodiment; [Figure 12] FIG. 2 is a diagram showing an example of a wall thickness / rigidity diagnosis process 1 according to the embodiment. [Figure 13] 11 is a diagram showing an example of a wall thickness / rigidity diagnosis process 2 according to the embodiment. FIG. [Figure 14] 11 is a diagram showing an example of a wall thickness / rigidity diagnosis process 3 according to the embodiment. FIG. [Figure 15] 11 is a diagram showing an example of a wall thickness / rigidity diagnosis process 4 according to the embodiment. FIG. [Figure 16] 5 is a diagram showing an example of a wall thickness / rigidity diagnosis process 5 according to the embodiment. FIG. [Figure 17] FIG. 11 is a diagram showing an example of the entire flow rate error diagnosis and simple correction process according to the embodiment. [Figure 18] FIG. 4 is a diagram showing an example of flow rate error diagnosis and simple correction processing 1 according to the embodiment. [Figure 19] FIG. 11 is a diagram showing an example of flow rate error diagnosis and simple correction processing 2 according to the embodiment. [Figure 20] FIG. 11 is a diagram showing an example of flow rate error diagnosis and simple correction processing 3 according to the embodiment. [Figure 21] FIG. 11 is a diagram showing an example of flow rate error diagnosis and simple correction processing 4 according to the embodiment. [Figure 22] FIG. 4 is a diagram showing an example of an entire timing prediction diagnosis process according to the embodiment; [Figure 23] FIG. 2 is a diagram showing an example of a timing prediction diagnosis process 1 according to the embodiment. [Figure 24] FIG. 4 is a diagram showing an example of a timing prediction diagnosis process 2 according to the embodiment. [Diagram 25] FIG. 11 is a diagram showing an example of a timing prediction diagnosis process 3 according to the embodiment. [Figure 26] FIG. 4 is a diagram showing an example of a timing prediction diagnosis process 4 according to the embodiment. [Figure 27] FIG. 11 is a diagram showing an example of a density diagnosis result according to the embodiment. [Figure 28] FIG. 2 is a diagram showing an example of a wall thickness / rigidity diagnosis result 1 according to the embodiment. [Figure 29] FIG. 11 is a diagram for explaining a wall thickness / rigidity diagnosis result 2 according to the embodiment. [Diagram 30] FIG. 11 is a diagram showing an example of a wall thickness / rigidity diagnosis result 2 according to the embodiment. [Diagram 31] FIG. 11 is a diagram showing an example of a thickness / rigidity diagnosis result 3-1 according to the embodiment. [Diagram 32] FIG. 13 is a diagram showing an example of a thickness / rigidity diagnosis result 3-2 according to the embodiment. [Diagram 33] FIG. 4 is a diagram showing an example of a flow rate diagnosis result 1 according to the embodiment. [Diagram 34] FIG. 2 is a diagram showing an example of a flow rate diagnosis result 2-1 according to the embodiment. [Diagram 35] FIG. 11 is a diagram showing an example of a flow rate diagnosis result 2-2 according to the embodiment. [Diagram 36] FIG. 11 is a diagram showing an example of a flow rate diagnosis result 2-3 according to the embodiment. [Figure 37] FIG. 11 is a diagram showing an example of a timing prediction diagnosis result according to the embodiment. [Figure 38] 10 is a flowchart showing an example of the overall flow of diagnostic processing according to the embodiment. [Figure 39] 1 is a flowchart showing an example of an overall flow of a density calibration process according to an embodiment. [Diagram 40] 10 is a flowchart showing an example of the overall flow of a density error diagnosis process according to the embodiment. [Diagram 41] 10 is a flowchart showing an example of the overall flow of a thickness stiffness diagnosis process according to the embodiment. [Diagram 42] 5 is a flowchart showing an example of the overall flow rate diagnosis and simple correction process according to the embodiment. [Diagram 43] 5 is a flowchart showing an example of the overall flow of a timing prediction diagnosis process according to the embodiment. [Diagram 44] FIG. 2 is a diagram illustrating an example of a hardware configuration according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A diagnostic device, a diagnostic method, and a diagnostic program according to an embodiment of the present invention will be described in detail below with reference to the drawings. Note that the present invention is not limited to the embodiment described below.

[0013] [Embodiment] The configuration of the diagnostic system (1000) according to this embodiment, the configuration of the Coriolis mass flowmeter (1), the configuration of each device in the diagnostic system (1000), details of each process of the calibration device (3) and the diagnostic device (2), the results of each process, and the flow of each process will be described below in order, and finally the effects of this embodiment will be described.

[0014] 1. Configuration of diagnostic system (1000) The configuration of the diagnostic system (1000) according to this embodiment will be described in detail with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the diagnostic system (1000) according to the embodiment. Below, an example of the overall configuration of the diagnostic system (1000), the processing of the diagnostic system (1000), the basic operation of the Coriolis mass flowmeter (1), and problems with the conventional technology will be described in this order, and finally, the effects of the diagnostic system (1000) will be described.

[0015] (1-1. Example of the overall configuration of the diagnostic system (1000)) The diagnostic system (1000) includes a Coriolis mass flowmeter (1), a diagnostic device (2), and a calibration device (3). The Coriolis mass flowmeter (1), the diagnostic device (2), and the calibration device (3) are connected to each other via a predetermined communication network (not shown) so as to be able to communicate with each other by wire or wirelessly. The diagnostic system (1000) shown in FIG. 1 may include a plurality of Coriolis mass flowmeters (1), a plurality of diagnostic devices (2), and a plurality of calibration devices (3). As will be described later with reference to FIG. 2, the Coriolis mass flowmeter (1) may have at least one of the diagnostic device (2) and the calibration device (3) as an internal device. The diagnostic device (2) and the calibration device (3) may be integrated into an external device (31).

[0016] (1-2. Overall processing of diagnostic system (1000)) The overall processing of the above-mentioned diagnostic system (1000) will be described. First, the calibration device (3) acquires the measurement value measured by the Coriolis mass flowmeter (1) (step S1). Next, the calibration device (3) executes density calibration processing of the Coriolis mass flowmeter (1) (step S2). Next, the diagnostic device (2) acquires the density calibration result (151) from the calibration device (3) (step S3), and executes density error diagnosis processing (step S4), wall thickness rigidity diagnosis processing (step S5), flow rate error diagnosis and simple correction processing (step S6), and timing prediction diagnosis processing (step S7) in this order. Then, the diagnostic device (2) transmits the diagnosis result of the above steps S4 to S7 to the Coriolis mass flowmeter (1) (step S8). In addition, the diagnostic device (2) transmits the calibration timing of the Coriolis mass flowmeter (1), which is the timing prediction diagnosis result of the above step S7, to the calibration device (3) (step S9). Note that the above steps S1 to S9 can be executed in a different order. Furthermore, among the above steps S1 to S9, some of the processes may be omitted.

[0017] (1-3. Basic operation of Coriolis mass flowmeter (1)) 2-3 and equations, a basic operation of the Coriolis mass flowmeter 1 in the diagnostic system 1000 will be described. The basic configuration, measurement equation, and operation of the Coriolis mass flowmeter 1 will be described below in that order.

[0018] (1-3-1. Basic configuration of Coriolis mass flowmeter (1)) The basic configuration of the Coriolis mass flowmeter (1) will be described with reference to Fig. 2. Fig. 2 is a block diagram showing an example of the configuration of the Coriolis mass flowmeter (1) according to the embodiment. As shown in Fig. 2, the Coriolis mass flowmeter (1) has a detection unit (10), a conversion unit (20), and a display operation unit (30). In addition, the Coriolis mass flowmeter (1) is connected to an external device (31).

[0019] The detection unit (10) has one or more vibration tubes (11), a vibration unit (12), two or more sensors (13, 14) that measure vibration, and a temperature sensor (15). Here, the upstream sensor (13) transmits an upstream signal S1 (13a) to the conversion unit (20). Also, the downstream sensor (14) transmits a downstream signal S2 (14a) to the conversion unit (20). The temperature sensor (15) measures at least one of the temperature of the vibration tube (11) and the temperature of the fluid, and transmits a temperature signal T (15a) to the conversion unit (20). The vibration unit (12) receives an excitation signal drive (12a) from the conversion unit (20) and vibrates the vibration tube (11).

[0020] The conversion unit (20) has a drive control unit (21), a mass flow rate calculation unit (22), and a density calculation unit (23). The drive control unit (21) changes the excitation signal drive (12a) so that at least one of the amplitude of the upstream signal S1 (13a) and the amplitude of the downstream signal S2 (14a) becomes a target value. The mass flow rate calculation unit (22) calculates the mass flow rate from the phase difference and frequency of the upstream signal S1 (13a) and the downstream signal S2 (14a). The mass flow rate calculation unit (22) also performs temperature correction using the temperature signal T (15a). The density calculation unit (23) calculates the density of the fluid from at least one of the frequency of the upstream signal S1 (13a) and the frequency of the downstream signal S2 (14a). The density calculation unit (23) also performs temperature correction using the temperature signal T (15a).

[0021] The conversion unit (20) transmits the measured numerical value to the display operation unit (30) as a status value (32a). The conversion unit (20) also transmits the measured numerical value to the external device (31) as a status value (32b). Meanwhile, the display operation unit (30) transmits an operation amount (33a) to the conversion unit (20) and sets the operation and the measurement coefficient. The external device (31) also transmits an operation amount (33b) to the conversion unit (20) and sets the operation and the measurement coefficient.

[0022] Here, the conversion unit (20) may also have a calibration control unit (40b) that executes a calibration process for measuring at least one of mass flow rate and density for the Coriolis mass flowmeter (1). The conversion unit (20) may also have a diagnosis control unit (60b) that executes a diagnosis process for the Coriolis mass flowmeter (1).

[0023] The external device (31) holds a reference flow meter and calibrates the Coriolis mass flowmeter (1) by flowing a fluid, and includes a calibration control unit (40a) and a diagnosis control unit (60a). The calibration control unit (40a) includes a density calibration unit (51a) and a mass flow calibration unit (41a). The density calibration unit (51a) performs a density calibration process by measuring the frequency of a plurality of fluids having known densities. The mass flow calibration unit (41a) performs a mass flow calibration process. The diagnosis control unit (60a) also performs a diagnosis process by a diagnosis device (2) according to an embodiment described below.

[0024] Meanwhile, the calibration control unit (40b) of the conversion unit (20) of the Coriolis mass flowmeter (1) can also execute a calibration process, similar to the calibration control unit (40a) of the above-described external device (31). Moreover, the diagnosis control unit (60b) of the conversion unit (20) of the Coriolis mass flowmeter (1) can also execute a diagnosis process by a diagnosis device (2) according to an embodiment described below, similar to the diagnosis control unit (60a) of the above-described external device (31).

[0025] As described above, in the diagnostic system (1000) according to the embodiment, the diagnostic control unit (60) that executes various diagnostic processes is configured as either or both of the diagnostic control unit (60a) included in the external device (31) and the diagnostic control unit (60b) included in the conversion unit (20) inside the Coriolis mass flowmeter (1).

[0026] (1-3-2. Measurement formula of Coriolis mass flowmeter (1)) The measurement formula of the Coriolis mass flowmeter (1) is explained below. First, according to JIS B7555 "Explanation of flow measurement method by Coriolis meter (mass flow rate, density and volumetric flow rate measurement)", the mass flow rate Qm is measured by the following formula (1).

[0027]

number

[0028] Here, the variable Ks indicates the rigidity (spring constant) of the vibrating tube in the torsional direction. The variable ω indicates the vibration angular velocity of the vibrating tube. The variable d indicates the width of the U-shaped vibrating tube. The variable L indicates the length of the U-shaped vibrating tube in the vibration direction. The variable K1 indicates a constant. The variable ωs indicates the natural frequency in the torsional direction. The variable ωu indicates the natural angular frequency in the vibration direction. The variable θ0 indicates the phase difference corresponding to the torsion.

[0029] To measure the actual mass flow rate, the following measurement equation (2) is used.

[0030]

number

[0031] In the Coriolis mass flowmeter (1), the vibrating tube vibration frequency f and the phase difference θ0 are measured and multiplied by the flow measurement coefficient Cq to obtain the mass flow rate Qm. At this time, the flow measurement coefficient Cq is determined by the mass flow calibration unit (41) and is defined as the flow measurement coefficient Cq (28f). The phase difference θ0 is also measured and is defined as the phase difference θ (28d). The frequency f is also measured and is defined as the frequency f (28c). The mass flow rate Qm is then calculated using the above formula (2) and is defined as the mass flow rate Qm (28a).

[0032] In the vibration of the oscillating tube (11) of the Coriolis mass flowmeter (1), the relationship between the stiffness (spring constant) K of the oscillating tube (11), the total mass M of the oscillating tube (11), and the vibration angular frequency ω of the oscillating tube (11) is expressed by the following equation (3), where the variable f indicates the vibration frequency of the oscillating tube (11).

[0033]

number

[0034] The total mass M of the vibration tube (11) is the sum of the mass Mu of the vibration tube (11), the mass Md of the accessories connected to the vibration tube (11), such as two or more sensors (13, 14) and the vibration unit (12), and the mass Mf of the fluid inside the vibration tube (11), and is expressed by the following (4).

[0035]

number

[0036] The mass Mf of the fluid in the vibration tube (11) is expressed by the following formula (5) using the volume of the fluid, that is, the internal volume V of the vibration tube (11), and the density ρ of the fluid.

[0037]

number

[0038] Here, from the above formulas (3), (4), and (5), the following formulas (6) and (7) are given.

[0039]

number

[0040]

number

[0041] Here, density ρ is a function of vibration frequency f. The above formula (7) includes the rigidity K of the vibrating tube (11), the internal volume V of the vibrating tube (11), the mass Mu of the vibrating tube (11) itself, and the mass Md of the accessories. Therefore, these coefficients must be calculated in order to measure the density.

[0042] A fluid with a known density ρ is measured. If the density is ρa, the vibration frequency is fa, and the rigidity of the vibration tube (11) is Ka, the following equation (8) is established from the above equation (6).

[0043]

number

[0044] In addition, if the stiffness Ka of the vibration pipe (11) is equal to the stiffness K of the vibration pipe (11) during measurement, it is expressed by the following formula (9).

[0045]

number

[0046] Incidentally, the rigidity of the vibration pipe (11) changes depending on the temperature, etc., so strictly speaking, the above formula (9) does not hold. Therefore, correction based on the temperature, etc. is required.

[0047] From the above equations (6), (8), and (9), the following equation (10) is obtained.

[0048]

number

[0049] Here, we define the density measurement coefficient Cd. As expressed by the following formula (11), the density measurement coefficient Cd is the sum of the mass of the vibration tube and accessories divided by the internal volume of the vibration tube, and has the same units as density.

[0050]

number

[0051] Moreover, from the above formulas (10) and (11), the following formulas (12) and (13) hold true.

[0052]

number

[0053]

number

[0054] In the Coriolis mass flowmeter (1), the density measurement coefficient Cd and frequency fa are determined by the density calibration unit (51) and are defined as the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l), respectively. Also, the vibration frequency f of the vibration tube (11) is measured and defined as the frequency f (28c). Then, the density ρ is calculated from the above formula (12) and defined as the density ρ (28b).

[0055] Here, the above formula (12) shows that if the density measurement coefficient Cd and the frequency fa at the fluid density ρa are measured in advance, the density ρ of the unknown fluid can be calculated from the frequency f. In this case, the fluid density ρa and frequency fa use the values ​​of air or vacuum at standard temperature and pressure. When measuring liquids, the span error can be reduced by using the density of a liquid with a close density, such as water.

[0056] Moreover, the above formula (13) indicates that as the density ρ increases, the frequency f decreases. Furthermore, as the density measurement coefficient Cd increases, the change in frequency f relative to the change in density ρ decreases.

[0057] From the above, the relationship between the density measurement coefficient Cd and the rigidity K is expressed by the following equation (14).

[0058]

number

[0059] (1-3-3. Operation of Coriolis mass flowmeter (1)) The operation of the Coriolis mass flowmeter (1) will be described with reference to FIG. 3. FIG. 3 is a diagram showing an example of a measurement process of the Coriolis mass flowmeter (1) according to the embodiment. As shown in FIG. 3, the Coriolis mass flowmeter (1) has a detection unit (10) and a conversion unit (20). The detection unit (10) also has an excitation unit (12), an upstream sensor (13), a downstream sensor (14), and a temperature sensor (15). The conversion unit (20) also has a drive control unit (21) including an amplitude calculation unit (21a), an amplitude control unit (21b), a multiplier (21c), an excitation circuit (21d), and a current amplitude calculation unit (21e), a mass flow rate calculation unit (22), a density calculation unit (23), a phase difference calculation unit (24a), a frequency calculation unit (24b), an amplitude calculation unit (24c), an amplitude calculation unit (24d), a temperature calculation unit (24e), and a pressure selection switch (24f).

[0060] First, the upstream sensor (13) of the detection unit (10) outputs an upstream signal S1 (13a), and the downstream sensor (14) of the detection unit (10) outputs a downstream signal S2 (14a).

[0061] Next, the drive control section (21) of the conversion section (20) controls the excitation signal drive (12a) so that the amplitude of the upstream signal S1 (13a) becomes the amplitude target value (27c). Here, the amplitude calculation section (21a) outputs the amplitude of the upstream signal S1 (13a). The amplitude control section (21b) calculates the drive gain (27b) from the amplitude calculated by the amplitude calculation section (21a) and the amplitude target value (27c). At this time, P control, PI control, or the like is used. The multiplier (21c) multiplies the upstream signal S1 (13a) by the drive gain (27b) to calculate a control signal. The excitation circuit (21d) creates the excitation signal drive (12a) from the control signal. Then, the excitation section (12) of the detection section (10) is driven by the excitation signal drive (12a). At this time, the excitation section (12) converts the current into a force. Moreover, the current amplitude calculation unit (21e) outputs the amplitude of the current value output by the excitation circuit (21d) as a drive current (27a).

[0062] 3, the amplitude control is performed by the upstream signal S1 (13a), but the amplitude control can also be performed by the downstream signal S2 (14a). Also, both the upstream signal S1 (13a) and the downstream signal S2 (14a) can be used.

[0063] The amplitude calculation unit (24c) of the conversion unit (20) outputs the amplitude S1 (27d) of the upstream signal S1 (13a). The amplitude calculation unit (24d) outputs the amplitude S2 (27e) of the downstream signal S2 (14a). The amplitude calculation units (24c, 24d) can perform output processing simultaneously with the phase difference calculation using a Hilbert transform or the like. The phase difference calculation unit (24a) of the conversion unit (20) calculates the phase difference θ (28d) from the upstream signal S1 (13a) and the downstream signal S2 (14a). The frequency calculation unit (24b) of the conversion unit (20) calculates the frequency f (28c) from at least one of the upstream signal S1 (13a) and the downstream signal S2 (14a). The temperature calculation unit (24e) of the conversion unit (20) calculates the temperature T (28e) from the temperature signal T (15a).

[0064] The mass flow calculation unit (22) of the conversion unit (20) calculates the mass flow rate Qm (28a) from the phase difference θ (28d) and the frequency f (28c) by the above-mentioned formula (2). The mass flow calculation unit (22) calculates the mass flow rate Qm (28a) by using the flow measurement coefficient Cq (28f). Here, the mass flow rate Qm (28a) depends on temperature, pressure, and density. Since the Coriolis mass flowmeter (1) cannot measure pressure, an external pressure gauge (29) is attached to obtain an external input pressure Pin (28r) or set a default pressure Ps (28q). When the pressure gauge (29) is connected, a pressure gauge connection signal (28s) is set. The pressure selection switch (24f) outputs the external input pressure Pin (28r) or the default pressure Ps (28q) according to the pressure gauge connection signal (28s), and sets it as the pressure P (28t). At this time, the mass flow rate calculator (22) corrects the mass flow rate Qm (28a) by using a flow rate measurement correction coefficient (28g) and at least one of the temperature T (28e), the density ρ (28b), and the pressure P (28t).

[0065] The density calculation unit (23) of the conversion unit (20) calculates the density ρ (28b) from the frequency f (28c) by the above-mentioned formula (12). The density calculation unit (23) calculates the density ρ (28b) by using the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l). Here, the density ρ (28b) depends on the temperature and the pressure. At this time, the density calculation unit (23) corrects the density ρ (28b) by using the density measurement correction coefficient (28m) and at least one of the temperature T (28e) and the pressure P (28t). Note that this correction is not a correction for a change in the measurement target, but a correction for a situation in which the above-mentioned formula (9) does not hold due to a change in the rigidity of the vibration tube (11) or the like. The density calculation unit (23) corrects the frequency to a specified state, for example, 20° C. and 1 atm.

[0066] The conversion unit (20) stores all of the coefficients, set values, and measurement results used in the above-mentioned calculations as control parameters (27) and parameters (28). The calibration control unit (40) and diagnosis control unit (60) operate by reading and setting the values ​​of these parameters.

[0067] (1-4. Issues with the prior art) Below, the problems with the conventional technology will be described in the order of stiffness damping diagnosis processing, corrosion diagnosis processing, density calibration processing, flow rate calibration processing, and prediction processing for maintenance, etc.

[0068] (1-4-1. Stiffness damping diagnostic processing and corrosion diagnostic processing) Conventional stiffness attenuation diagnostic processing and corrosion diagnostic processing use amplitude information, so they are affected by the amplification sensitivity of the drive circuit and measurement circuit. In addition, conventional processing performs diagnosis using input and output signals of the converter, so it includes unmeasurable characteristics such as changes in magnetic flux density of the magnets of the driver and pick-off and gain of the circuit. Therefore, conventional processing cannot measure the absolute value of the stiffness of the vibration tube, and determines the relative value.

[0069] In addition, the conventional processing measures the amplitude, and is therefore subject to the effects of vibration, temperature, and the like. Here, the mass flow rate and density of the Coriolis mass flowmeter are measured from the phase difference and frequency, and the accuracy of the amplitude measurement is low. Furthermore, in the conventional processing, the drive gain is fixed, and a special mechanism is required for the converter, such as measuring the rate of change of the amplitude, and therefore heavy calculations are required in addition to the normal mass flow rate and density measurements. Also, in the conventional processing, corrosion is determined by the rigidity, and the thickness change is not directly obtained. Here, the cause of the stiffness change is not limited to corrosion. The density error diagnosis processing and the thickness stiffness diagnosis processing executed by the diagnosis system (1000) contribute to solving the above problems.

[0070] (1-4-2. Density calibration process) In conventional density calibration processing, changing parameters creates discontinuities in the measurement results. This becomes a factor of variation, particularly when calibration is performed frequently. Even with conventional processing, it is possible to calculate density error from the difference with the known density of the fluid used for calibration at the time of calibration, but the density error depends on the density of the object to be measured. Here, since the purpose of a Coriolis mass flowmeter is to measure mass flow rate and density, it is necessary to understand the density error in order to guarantee performance. The density calibration processing and density error diagnosis processing executed by the diagnostic system (1000) contribute to solving the above problems.

[0071] (1-4-3. Flow rate calibration process) Conventional flow rate calibration processes require a device that provides a known flow rate or a standard mass flow meter, and the calibration device is large in size. In addition, in conventional processes, mass flow rate calibration requires removing the device and transporting it to a calibration facility for calibration, which results in a large amount of expense and time when the flow meter cannot be used. Since measurement accuracy is important, calibration is performed during regular maintenance. In conventional processes, there are attempts to calibrate Coriolis mass flow meters at the site of use, but this requires a compact flow rate calibration device. Here, since the purpose of the Coriolis mass flow meter is to measure mass flow rate and density, it is necessary to grasp the flow rate error in order to guarantee performance. The flow rate error diagnosis and simple correction process performed by the diagnostic system (1000) contributes to solving the above problems.

[0072] (1-4-4. Prediction of maintenance, etc.) Conventional maintenance and replacement timing prediction processes predict timing based on stiffness or damping. It is difficult to determine the value that requires maintenance based on these parameters alone. The timing prediction diagnostic process executed by the diagnostic system (1000) contributes to solving the above problem.

[0073] (1-5. Effects of diagnostic system (1000)) In the following, the effects of the diagnostic system (1000) will be described in the order of density error diagnostic processing, thickness stiffness diagnostic processing, flow rate error diagnostic processing / simple correction processing, and timing prediction diagnostic processing.

[0074] (1-5-1. Density error diagnosis process and thickness stiffness diagnosis process) As described above, in the diagnostic system (1000), the diagnostic device (2) generates a density diagnostic result related to the density error of the fluid before and after the density calibration based on a density calibration result related to the calibration of the density of the fluid generated by calibrating the Coriolis mass flowmeter (1) that measures the flow rate and density of the fluid flowing through the vibrating tube (11) based on the Coriolis force acting on the vibrated vibrating tube (11), and performs a calculation related to at least one of the thickness and rigidity of the vibrating tube (11) based on the density diagnostic result to generate a thickness and rigidity diagnostic result related to the change in the vibrating tube (11). The diagnostic device (2) also calculates the density error using the initial density measurement coefficient, the density measurement coefficient indicated by the density calibration result, and the density of the measurement target, and generates a thickness and rigidity diagnostic result including at least one of the results related to the thickness change and rigidity change of the vibrating tube (11) using the rate of change of the density measurement coefficient indicated by the density calibration result and the design value of the vibrating tube (11), and detects an abnormality related to the vibrating tube (11) when the thickness and rigidity diagnostic result is equal to or greater than a threshold value. Furthermore, the diagnostic device (2) generates a thickness / rigidity diagnostic result including at least one of the inner diameter, thickness, thickness change, thickness change rate, rigidity change rate, corrosion diagnosis, and adhesion diagnosis of the vibration pipe (11).

[0075] Therefore, the diagnostic system (1000) can determine corrosion of the oscillating tube without using amplitude information that is affected by the amplification sensitivity of the drive circuit and the measurement circuit, and can accurately diagnose the condition of the oscillating tube of the Coriolis mass flowmeter (1). Also, the diagnostic system (1000) can directly determine the change in wall thickness of the oscillating tube, and can easily diagnose failures and performance degradation of the Coriolis mass flowmeter (1).

[0076] (1-5-2. Flow rate error diagnosis and simple correction process) As described above, in the diagnostic system (1000), the diagnostic device (2) performs calculations on the flow rate of the fluid based on the thickness / rigidity diagnostic result, and generates a flow rate diagnostic result on the flow rate error of the fluid. The diagnostic device (2) also calculates a flow rate correction coefficient using at least one of the stiffness change rate, the thickness change rate, and the change rate of the density measurement coefficient, and performs update control of the flow rate correction coefficient used by the Coriolis mass flowmeter (1) to measure the flow rate based on the calculated flow rate correction coefficient. Therefore, in the diagnostic system (1000), the mass flow rate can be simply corrected from stiffness change, thickness change, density measurement coefficient change, and the like, without calibrating the mass flow rate in a calibration facility.

[0077] (1-5-3. Timing prediction diagnostic processing) As described above, in the diagnostic system (1000), the diagnostic device (2) predicts the occurrence of a fault in the Coriolis mass flowmeter (1), the time required for maintenance or equipment replacement, the operating time, or the integrated flow rate of the fluid based on the density calibration result, the density diagnostic result, the wall thickness / rigidity diagnostic result, or the flow rate diagnostic result, and generates these as timing prediction diagnostic results. Therefore, in the diagnostic system (1000), by using either the result of the calibration process or the result of each diagnostic process, it is possible to more accurately and easily predict the timing of maintenance, etc.

[0078] 2. Configuration of each device in the diagnostic system (1000) The functional configuration of each device of the diagnostic system (1000) shown in FIG. 1 will be described with reference to FIG. 4. FIG. 4 is a block diagram showing an example of the configuration of each device of the diagnostic system according to the embodiment. Below, an example of the configuration and processing of the diagnostic system (1000) as a whole will be described, and then an example of the configuration of the diagnostic device (2) will be described. In FIG. 4, the solid arrows indicate information such as signals, and the dashed arrows indicate triggers for processing.

[0079] (2-1. Example of the overall configuration of the diagnostic system (1000)) As shown in Fig. 4, the diagnostic system (1000) has a Coriolis mass flowmeter (1), a diagnostic device (2), and a calibration device (3). In Fig. 4, the Coriolis mass flowmeter (1), the diagnostic device (2), and the calibration device (3) are shown as separate devices, but two or three of the above three devices may be integrated into one configuration. Note that the configuration and processing of the Coriolis mass flowmeter (1) are common to the configuration and processing of the Coriolis mass flowmeter (1) described in (1-3-1. Basic configuration of the Coriolis mass flowmeter (1)), and therefore will not be described here.

[0080] In addition, the configuration and processing overview of the calibration control unit (40) of the calibration device (3) are common to the calibration control unit (40) in the external device (31) or the conversion unit (20) of the Coriolis mass flowmeter (1) described in (1-3-1. Basic configuration of the Coriolis mass flowmeter (1)), so a description thereof will be omitted. However, the details of the configuration and processing of the calibration control unit (40) will be described later in [3. Details of each process of the calibration device (3) and the diagnosis device (2)].

[0081] (2-2. Overall processing of diagnostic system (1000)) 4, the calibration device (3) executes density calibration processing by the density calibration unit (51). The diagnosis device (2) executes diagnosis processing in the following order: density error diagnosis processing by the density error diagnosis unit (61), thickness stiffness diagnosis processing by the thickness stiffness diagnosis unit (70), flow rate error diagnosis and simple correction processing by the flow rate error diagnosis simple correction unit (80), and timing prediction diagnosis processing by the timing prediction diagnosis unit (90). That is, in the diagnosis system (1000), the diagnosis device (2) executes each diagnosis from a change in the density measurement coefficient obtained by the density calibration unit (51) as shown below.

[0082] (2-2-1. Density calibration process) As the first process, the density calibration process will be described. First, the density calibration unit (51) of the calibration device (3) outputs the density calibration result (151) and updates the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l). The density calibration unit (51) measures the frequency f (28c) of a measurement object whose density is known, and obtains the density measurement coefficient. The density calibration unit (51) uses only the density of the measurement object and the frequency f (28c) obtained by the frequency calculation unit (24b) of the Coriolis mass flowmeter (1). The density calibration unit (51) sets a density calibration completion signal (160) at the end of execution. The mass flow calibration unit (41) of the calibration device (3) measures the frequency f (28c) and the phase difference θ (28d) at a known flow rate, and obtains the flow rate measurement coefficient Cq (28f). Then, the mass flow rate calibration unit (41) sets a flow rate calibration completion signal (120) when the process is completed.

[0083] (2-2-2. Density error diagnosis process) As the second process, the density error diagnosis process will be described. First, the density error diagnosis unit (61) of the diagnosis device (2) executes the process when the density calibration completion signal (160) is set. At this time, the density error diagnosis unit (61) executes the density error diagnosis process from a change in the density measurement coefficient included in the density calibration result (151). The density error diagnosis unit (61) also stores the process result in the density diagnosis result (201). Then, when the process ends, the density error diagnosis unit (61) resets the density calibration completion signal (160) and sets the density diagnosis completion signal (210).

[0084] (2-2-3. Thickness and rigidity diagnostic processing) As the third process, the thickness / rigidity diagnosis process will be described. First, the thickness / rigidity diagnosis unit (70) of the diagnosis device (2) executes the process when the density diagnosis completion signal (210) is set. At this time, the thickness / rigidity diagnosis unit (70) obtains the rate of change of thickness and rigidity from the change in the density measurement coefficient, and performs diagnosis. The thickness / rigidity diagnosis unit (70) also stores the process result in the thickness / rigidity diagnosis result (301). Then, the thickness / rigidity diagnosis unit (70) resets the density diagnosis completion signal (210) when the process ends. Then, the thickness / rigidity diagnosis unit (70) sets the thickness / rigidity diagnosis completion signal (310).

[0085] (2-2-4. Flow rate error diagnosis and simple correction process) As the fourth process, the flow rate error diagnosis and simple correction process will be described. First, the flow rate error diagnosis simple correction unit (80) of the diagnosis device (2) executes the process when the thickness stiffness diagnosis completion signal (310) or the flow rate calibration completion signal (120) is set. At this time, the flow rate error diagnosis simple correction unit (80) reduces the flow rate error and diagnoses the flow rate error by updating the flow rate correction coefficient fk (28u) based on the change in the density measurement coefficient, the change in the thickness, the change in the stiffness, etc. In addition, the flow rate error diagnosis simple correction unit (80) saves the process result in the flow rate diagnosis result (501). When the process ends, the flow rate error diagnosis simple correction unit (80) resets the thickness stiffness diagnosis completion signal (310) and the flow rate calibration completion signal (120).

[0086] (2-2-5. Timing prediction diagnostic processing) As the fifth process, a timing prediction diagnosis process will be described. First, the timing prediction diagnosis unit (90) of the diagnosis device (2) predicts the time when the target value will be reached by using the density calibration result (151), density diagnosis result (201), wall thickness stiffness diagnosis result (301), or flow rate diagnosis result (501). At this time, the timing prediction diagnosis unit (90) sets a threshold value to predict the time required until a failure occurs or a state where maintenance is required, the operating time, or the accumulated flow rate of the fluid.

[0087] (2-3. Configuration example of diagnostic device (2)) A configuration example of the diagnostic device (2) according to the embodiment will be described below. As shown in Fig. 4, the diagnostic device (2) has a diagnostic control unit (60), a transmitting / receiving unit (200), and a notification unit (300). The diagnostic device (2) may also have an input unit (e.g., a keyboard, a mouse, etc.) that accepts various operations from an administrator of the diagnostic device (2), and a display unit (e.g., a liquid crystal display, etc.) that displays various information.

[0088] (2-3-1. Diagnosis control unit (60)) The diagnostic control unit (60) is realized, for example, by a central processing unit (CPU), a micro processing unit (MPU), etc., executing various programs (corresponding to an example of an information processing program) stored in a storage device inside the diagnostic device (2) using a RAM as a working area. The diagnostic control unit (60) is also realized, for example, by an integrated circuit such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA).

[0089] As shown in Fig. 4, the diagnosis control unit (60) has a density error diagnosis unit (61), a wall thickness rigidity diagnosis unit (70), a flow rate error diagnosis simple correction unit (80), and a timing prediction diagnosis unit (90), and realizes or executes the functions and actions of information processing described below. The internal configuration of the diagnosis control unit (60) is not limited to the configuration shown in Fig. 4, and may be other configurations as long as they perform information processing described below. Furthermore, the connection relationship between the processing units of the diagnosis control unit (60) is not limited to the connection relationship shown in Fig. 4, and may be other connection relationships.

[0090] (2-3-1-1. Density error diagnosis unit (61)) The density error diagnosis unit (61) generates a density diagnosis result (201) relating to the density error of the fluid before and after the density calibration, based on a density calibration result (151) relating to the calibration of the density of the fluid, which is generated by calibrating a Coriolis mass flowmeter (1) that measures the flow rate and density of the fluid flowing through the vibrating tube (11) based on the Coriolis force acting on the vibrated vibrating tube (11).

[0091] For example, the density error diagnosis unit (61) calculates a density error Δρ0 using the initial density measurement coefficients (Cd0, fa0), the density measurement coefficients (Cdc, fac) indicated by the density calibration result, and the density ρt of the object to be measured. The density error diagnosis unit (61) also calculates a rate of change (aCd, afa) of the density measurement coefficients using the initial density measurement coefficients (Cd0, fa0), the density measurement coefficients (Cdc, fac) indicated by the density calibration result, and the density ρt of the object to be measured.

[0092] Furthermore, the density error diagnosis unit (61) calculates a density fluctuation Δρ0 that occurs when the density measurement coefficients are updated, using the density measurement coefficients (Cd0, fa0) before the change, the density measurement coefficients (Cdc, fac) indicated by the density calibration result, and the density ρt of the measurement object, and if the density fluctuation exceeds a tolerance, detects an abnormality related to the vibrating tube (11).

[0093] (2-3-1-2. Thickness and rigidity diagnosis section (70)) The thickness / rigidity diagnosis unit (70) performs calculations on at least one of the thickness and rigidity of the vibration tube (11) based on the density calibration result (151) and generates a thickness / rigidity diagnosis result (301) on the change in the vibration tube (11). For example, the thickness / rigidity diagnosis unit (70) generates a thickness / rigidity diagnosis result (301) including at least one of the results on the change in the thickness and rigidity of the vibration tube (11) using the change rate (aCd, afa) of the density measurement coefficient indicated by the density calibration result (151) or the density diagnosis result (201) and the design values ​​(inner diameter d of the vibration tube, outer diameter D of the vibration tube) of the vibration tube (11), and detects an abnormality in the vibration tube (11) when the thickness / rigidity diagnosis result (301) is equal to or greater than a threshold value. Further, the thickness / rigidity diagnosis unit (70) generates a thickness / rigidity diagnosis result (301) including at least one of the inner diameter dc, the thickness tc, the thickness change dt, the thickness change rate rt, and the rigidity change rate aK of the vibration pipe (11).

[0094] Furthermore, the thickness / rigidity diagnosis unit (70) uses the results regarding the changes in thickness and rigidity of the vibrating tube (11) to perform a fault diagnosis of the Coriolis mass flowmeter (1), including at least one of a thickness diagnosis, a rigidity diagnosis, a corrosion diagnosis, and an adhesion diagnosis, and if the above results exceed an alarm value, detects a fault in the Coriolis mass flowmeter (1).

[0095] (2-3-1-3. Flow rate error diagnosis simple correction unit (80)) The flow rate error diagnosis simple correction unit (80) executes a calculation related to the flow rate of the fluid based on the thickness / rigidity diagnosis result (301) and generates a flow rate diagnosis result (501) related to the flow rate error of the fluid. For example, the flow rate error diagnosis simple correction unit (80) calculates a flow rate correction coefficient fkq using at least one of the stiffness change rate aK, the thickness change rate dt, and the change rate adc of the density measurement coefficient, and executes update control of the flow rate correction coefficient used by the Coriolis mass flowmeter (1) to measure the flow rate based on the calculated flow rate correction coefficient fkq.

[0096] At this time, the flow rate error diagnosis simple correction unit (80) calculates the flow rate fluctuation rate rqd when the flow rate correction coefficient is updated, using the flow rate correction coefficient fk before the change and the calculated flow rate correction coefficient fkq, and if the flow rate fluctuation rate exceeds an allowable value, updates the flow rate measurement coefficient used by the Coriolis mass flowmeter (1) to measure the flow rate. The flow rate error diagnosis simple correction unit (80) can also determine in advance the type of rate of change and weighting coefficient used in calculating the flow rate correction coefficient fkq from the results of a simulation or experiment.

[0097] (2-3-1-4. Timing Prediction and Diagnosis Unit (90)) The timing prediction diagnosis unit (90) predicts the occurrence of a fault in the Coriolis mass flowmeter (1), the time required for maintenance or equipment replacement, the operating time, or the accumulated flow rate of the fluid based on the density calibration result (151), the density diagnosis result (201), the wall thickness / rigidity diagnosis result (301), or the flow rate diagnosis result (501), and generates the result as a timing prediction diagnosis result (603).

[0098] For example, the timing prediction diagnosis unit (90) uses at least one of the calculated density measurement coefficients (Cdc, fac), density measurement coefficient change rate (aCdc, afac), and density error Δρ0 as the density diagnosis result (201) and outputs it as the timing prediction diagnosis result (603). Also, the timing prediction diagnosis unit (90) uses at least one of the inner diameter dc, thickness tc, thickness change dt, and thickness change rate rt of the vibration tube (11) as the thickness rigidity diagnosis result (301) and outputs it as the timing prediction diagnosis result (603). Also, the timing prediction diagnosis unit (90) uses at least one of the flow rate correction coefficient fkq and flow rate error rate rqe as the flow rate diagnosis result (501) and outputs it as the timing prediction diagnosis result (603).

[0099] The timing prediction diagnosis unit (90) also obtains an approximation line or approximation curve indicating the change with time of a parameter included in the density calibration result (151), the density diagnosis result (201), the wall thickness / rigidity diagnosis result (301) or the flow rate diagnosis result (501), the change with respect to the operating time of the parameter, or the change with respect to the integrated flow rate of the parameter, and predicts the time, operating time or integrated flow rate of the fluid until the approximation line or approximation curve reaches a diagnostic target value specified as a state in which a fault has occurred and maintenance or replacement of equipment is required, and outputs the result as a timing prediction diagnosis result (603).

[0100] (2-3-2. Transmitter / receiver (200)) The transmitting / receiving unit (200) is realized by, for example, a network interface card (NIC) or the like. For example, the transmitting / receiving unit (200) acquires a density calibration result (151) from a calibration device (3). The transmitting / receiving unit (200) is connected to a predetermined communication network by wire or wirelessly, and transmits and receives information to and from various devices.

[0101] (2-3-3. Notification Department (300)) The notification unit (300) notifies of an abnormality related to the vibrating pipe (11) when the density calibration result (151), the density diagnosis result (201), the wall thickness / rigidity diagnosis result (301) or the flow rate diagnosis result (501) exceeds a predetermined alarm value.

[0102] [3. Details of each process of the calibration device (3) and the diagnosis device (2)] 5 to 26 and equations, the details of each process of the calibration device (3) and the diagnosis device (2) according to the embodiment will be described. The following describes the density calibration diagnosis process of the calibration device (3), the thickness stiffness diagnosis process of the diagnosis device (2), the flow rate error diagnosis and simple correction process, and the timing prediction diagnosis process in that order.

[0103] (3-1. Density calibration process) The density calibration process executed by the density calibration unit (51) of the calibration device (3) according to the embodiment will be described with reference to Fig. 5 and Fig. 6 and equations. Below, the theoretical equation of the density calibration process will be explained, followed by the overall density calibration process and the density calibration coefficient calculation process.

[0104] (3-1-1. Theoretical formula for density calibration process) The theoretical formula for density calibration processing is explained below. The density measurement coefficient Cd (28k) and density measurement coefficient fa (28l) are calibrated using fluids with two or more points of known density. The above formula (12) is considered to be a linear formula. If the coefficients after calibration are the density measurement coefficient Cdc and the density measurement coefficient fac, then the following formulas (15) to (18) are obtained.

[0105]

number

[0106]

number

[0107]

number

[0108]

number

[0109] Now consider calibration at two points. If the frequency in a material with density ρ1 is f1 and the frequency in a material with density ρ2 is f2, we obtain the following equations (19) and (20). Here, it is assumed that the frequencies f1 and f2 have been corrected so that the above-mentioned equation (9) holds.

[0110]

number

[0111]

number

[0112] The coefficients a and b are calculated as in the following equations (21) and (22).

[0113]

number

[0114]

number

[0115] The density measurement coefficient Cdc and the density measurement coefficient fac are calculated using the following equations (23) and (24).

[0116]

number

[0117]

number

[0118] When calibrating at three or more points, create the above formula (15) for each result and find the coefficients using the least squares method or the like.

[0119] (3-1-2. Overall density calibration process) The entire density calibration process will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a diagram showing an example of the entire density calibration process according to the embodiment. The configuration and process of the density calibration unit (51) of the calibration device (3) will be described below.

[0120] The configuration and processing of the density calibration unit (51) will be described with reference to Fig. 5. As shown in Fig. 5, the density calibration unit (51) has a density measurement coefficient calculation unit (52). The density measurement coefficient calculation unit (52) outputs a density calibration result (151) from the parameters (28) and a density calibration set value (152). The density measurement coefficient calculation unit (52) also sets a density calibration completion signal (160). Here, the density calibration completion signal (160) is used for the execution of the density error diagnosis unit (61) and is reset in the density error diagnosis unit (61) of the diagnosis device (2).

[0121] The density measurement coefficient calculation unit (52) sets the density calibration result (151) in the parameter (28). In addition, the density error diagnosis unit (61) described below determines whether or not the result can be set, and sets the result in the parameter (28). When the density error diagnosis unit (61) is used, no setting is made here.

[0122] (3-1-3. Density measurement coefficient calculation process) The density measurement coefficient calculation process by the density measurement coefficient calculation unit (52) of the density calibration unit (51) will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of the density calibration process according to the embodiment. As shown in Fig. 6, the density measurement coefficient calculation unit (52) has a frequency correction unit (53), a material selection switch (54), a standard density calculation unit (55), a density selection switch (56), a material selection switch (57), and a density measurement coefficient calculation execution unit (58).

[0123] Here, the manually input density ρin (152a) indicates a density value manually inputted via the display operation unit (30) or the external device (31). Also, the density selection (152b) indicates a signal for controlling the density selection switch (56) to select the standard density ρc (156) or the manually input density ρin (152a). The coefficient n (152c) indicates the number of the measured substance.

[0124] The frequency correction unit (53) corrects the frequency f (28c) using the density measurement correction coefficient (28m), the temperature T (28e), and the pressure P (28t), and outputs the corrected frequency fn (153). This correction is not for changes in the measurement target, but for a situation in which the above-mentioned formula (9) does not hold due to changes in the rigidity of the oscillating tube (11), etc. The frequency correction unit (53) corrects the frequency to a specified state, such as 20°C, 1 atm, etc. This processing is the same as the processing included in the density calculation unit (23).

[0125] The material selection switch (54) outputs the corrected frequency f1 (154) or the corrected frequency f2 (155) according to the coefficient n (152c). The standard density calculation unit (55) calculates the standard density ρc (156) from the temperature T (28e), the pressure P (28t), and the coefficient n (152c). The standard density calculation unit (55) operates when a density calculation formula corresponding to the target material is prepared. The density selection switch (56) selects the standard density ρc (156) or the manually input density ρin (152a) according to the density selection (152b), and sets it as the density ρn (157). The material selection switch (57) outputs the density ρ1 (158) or the density ρ2 (159) according to the coefficient n (152c).

[0126] The density measurement coefficient calculation execution unit (58) calculates the density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) by using the corrected frequency f1 (154), the corrected frequency f2 (155), the density ρ1 (158), and the density ρ2 (159) according to the above-mentioned equations (21) to (24).

[0127] The density measurement coefficient calculation unit (52) also stores the date and time (28x) in the calibration date and time (151x). Here, the date and time (28x) is the time held by the conversion unit (20) or the external device (31) and is the date and time when the calibration was performed. The density measurement coefficient calculation unit (52) also stores the conversion unit drive time (28y) in the drive time (151y). Here, the conversion unit drive time (28y) is held by the conversion unit (20) and indicates a value obtained by integrating the drive time of the conversion unit (20). The density measurement coefficient calculation unit (52) also stores the integrated flow rate (28z) in the integrated flow rate (151z). Here, the integrated flow rate (28z) is held by the conversion unit (20) and indicates a value obtained by integrating the mass flow rate.

[0128] When the density measurement coefficient calculation unit 52 ends the density measurement coefficient calculation process, it sets an update flag 151s and a density calibration completion signal 160. The update flag 151s is used by the timing prediction diagnosis unit 90.

[0129] (3-2. Density error diagnosis processing) 7 to 10 and equations, the density error diagnosis process executed by the density error diagnosis unit (61) of the diagnosis device (2) according to the embodiment will be described. Below, after explaining the theoretical equation of the density error diagnosis process, the overall density error diagnosis process, the initialization determination process, the density error initialization process, and the density error calculation determination process will be described in that order.

[0130] (3-2-1. Theoretical formula for density error diagnosis processing) The theoretical formula for the density error diagnosis process is explained below. First, the density fluctuation Δρ (201c) is calculated from the changes in the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l). Here, the density measurement coefficients obtained by density calibration are the density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b). Also, the density measurement coefficients before calibration are the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l). From the above formula (13), when a material with a measurement target density ρt (202c) is measured in the calibrated state, the frequency f is given by the following formula (25).

[0131]

number

[0132] An error occurs when calculating density using frequency f and the density measurement coefficient Cd (28k) and density measurement coefficient fa (28l), which are coefficients before calibration. If the density including the error is ρe, then we obtain the following equation (26).

[0133]

number

[0134] The density variation Δρ(201c) when the density measurement coefficient is changed can be calculated using the following equation (27).

[0135]

number

[0136] The density variation Δρ (201c) depends on the measured density ρt (202c) and indicates the density error that has occurred since the last density calibration.

[0137] Changing the density measurement coefficient creates discontinuities in the density measurement results. If the density fluctuation Δρ (201c) is within the allowable range, there is also the option of prioritizing the continuity of the measurement values. The density fluctuation allowable value (202d) is set as a variable ρlim, and is compared with the absolute value of the density fluctuation Δρ (201c) to determine whether or not the density measurement coefficient can be replaced, thereby suppressing the fluctuation in the density measurement results. In this case, the conditional formula is the following formula (28).

[0138]

number

[0139] When the density measurement coefficient is replaced, an alarm can be set. Also, the density fluctuation Δρ (201c) can be displayed on the display operation unit (30) or the external device (31), and it is also possible to input whether or not the density measurement coefficient is replaced.

[0140] The density measurement coefficients in the initial state at the time of shipment or the like are stored and designated as initial coefficients Cd0 (202a) and fa0 (202b). The density error Δρ0 (201d) from the initial state is calculated as in the following equation (29).

[0141]

number

[0142] When the absolute value of the density error Δρ0 (201d) becomes equal to or greater than the density error alarm value (202h), a density error abnormality (201h) is set. The density error alarm value (202h) is set as a variable ρ0lim. In this case, the conditional formula is the following formula (30).

[0143]

number

[0144] By setting a density error error (201h) due to an error from the initial value, the user is notified of an abnormality in the device. The occurrence of a density error indicates that an error has also occurred in the mass flow measurement results. The density error error (201h) notifies the user that readjustment of the measuring device is necessary.

[0145] When the coefficient change rate aCd (201e) is calculated from the initial coefficient Cd0 (202a) and the density measurement coefficient Cdc (151a), the following formula (31) is obtained.

[0146]

number

[0147] The coefficient change rate afa (201f) is calculated from the initial coefficient fa0 (202b) and the density measurement coefficient fac (151b) as shown in the following equation (32).

[0148]

number

[0149] The change from the previous calibration can be calculated by using the density measurement coefficient Cd and density measurement coefficient fa from the previous calibration.

[0150] An abnormality diagnosis is performed from the rate of change of the density measurement coefficient. It is judged whether the coefficient change rate aCd (201e) is greater than the coefficient change rate aCd tolerance (202i). The coefficient aCdlim indicates the coefficient change rate aCd tolerance (202i). If it is greater, a coefficient change rate aCd abnormality (201i) is set. If there is no change, the coefficient change rate aCd (201e) becomes the value 1.0. It is also possible to determine an upper and lower limit for the judgment. In this case, the conditional formula is the following formula (33).

[0151]

number

[0152] It is determined whether the coefficient change rate afa (201f) is greater than the coefficient change rate afa tolerance (202j). The coefficient afalim indicates the coefficient change rate afa tolerance (202j). If it is greater, a coefficient change rate afa abnormality (201j) is set. If there is no change, the coefficient change rate afa (201f) becomes the value 1.0. It is also possible to determine upper and lower limits for the determination. In this case, the condition formula is the following formula (34).

[0153]

number

[0154] (3-2-2. Overall density diagnostic processing) The overall density error diagnosis process will be described with reference to Fig. 7. Fig. 7 is a diagram showing an example of the overall density error diagnosis process according to the embodiment. The following describes the configuration of the density error diagnosis unit (61) of the diagnosis device (2).

[0155] 7, the density error diagnosis unit (61) is part of the diagnosis control unit (60), and executes processing when the density calibration completion signal (160) is set. The density error diagnosis unit (61) also has an initialization determination unit (62), a density error initialization unit (63), and a density error calculation determination unit (64). The density calibration unit (51) updates the parameters (28) immediately after calculation, but the density error diagnosis unit (61) determines whether to update based on the density fluctuation Δρ (201c).

[0156] The initialization determination unit (62) selects the process to be executed based on the density calibration completion signal (160) and the density diagnosis set value (202). At this time, if initialization is required, the initialization determination unit (62) sets an initialization signal (203) to execute a density error initialization unit (63). On the other hand, if initialization is not required, the initialization determination unit (62) sets a calculation determination signal (204) to execute a density error calculation determination unit (64).

[0157] The density error initialization unit (63) initializes the density diagnosis set value (202) and the density diagnosis result (201). Then, the density error initialization unit (63) resets the density calibration completion signal (160) when the process is completed, and sets the density diagnosis completion signal (210).

[0158] The density error calculation / determination unit (64) updates the density diagnosis result (201) and updates the density calibration coefficient of the parameter (28). Then, the density error calculation / determination unit (64) resets the density calibration completion signal (160) and sets the density diagnosis completion signal (210) when the process is completed.

[0159] (3-2-3. Initialization Judgment Process) The initialization determination process by the initialization determination unit (62) of the density error diagnosis unit (61) will be described with reference to FIG. 8. FIG. 8 is a diagram showing an example of density error diagnosis process 1 according to the embodiment. As shown in FIG. 8, the initialization determination unit (62) executes processing when the density calibration completion signal (160) is set. The initialization determination unit (62) also outputs an initialization signal (203) and a calculation determination signal (204) based on the initial coefficient Cd0 (202a), the initial coefficient fa0 (202b), the initialization execution command (202u), and the initial date and time (202x) as the density diagnosis set value (202). The flow of the initialization determination process will be described later in [5. Flow of Processing by the Calibration Device (3) and the Diagnosis Device (2)].

[0160] (3-2-4. Density error initialization process) The density error initialization process by the density error initialization unit (63) of the density error diagnosis unit (61) will be described with reference to Fig. 9. Fig. 9 is a diagram showing an example of density error diagnosis process 2 according to the embodiment.

[0161] The density error initialization unit (63) stores the density calibration result (151) in the parameter (28) as follows: That is, the density error initialization unit (63) substitutes the value of the calibration date and time (151x) for the density calibration date and time (28n), the value of the drive time (151y) for the density calibration drive time (28o), the value of the integrated flow rate (151z) for the density calibration integrated flow rate (28p), the value of the density measurement coefficient Cdc (151a) for the density measurement coefficient Cd (28k), and the value of the density measurement coefficient fac (151b) for the density measurement coefficient fa (28l).

[0162] The density error initialization unit (63) uses the density calibration result (151) to set an initial value of the density diagnosis set value (202) as shown below. That is, the density error initialization unit (63) assigns the value of the calibration date and time (151x) to the initial date and time (202x), the value of the drive time (151y) to the initial drive time (202y), the value of the integrated flow rate (151z) to the initial integrated flow rate (202z), the value of the density measurement coefficient Cdc (151a) to the initial coefficient Cd0 (202a), and the value of the density measurement coefficient fac (151b) to the initial coefficient fa0 (202b). The density error initialization unit (63) also resets the initialization execution command (202u).

[0163] The density error initialization unit (63) initializes the density diagnosis result (201) as follows: That is, the density error initialization unit (63) substitutes the value of the calibration date and time (151x) for the diagnosis date and time (201x), the value of the drive time (151y) for the drive time (201y), the value of the integrated flow rate (151z) for the integrated flow rate (201z), the value of the density measurement coefficient Cdc (151a) for the density measurement coefficient Cd (201a), and the value of the density measurement coefficient fac (151b) for the density measurement coefficient fa (201b). The density error initialization unit (63) also sets the density fluctuation Δρ (201c) to a value of 0.0, sets the density error Δρ0 (201d) to a value of 0.0, sets the coefficient change rate aCd (201e) to a value of 1.0, and sets the coefficient change rate afa (201f) to a value of 1.0. The density error initialization unit (63) also resets the density error abnormality (201h), the coefficient change rate aCd abnormality (201i), and the coefficient change rate afa abnormality (201j). Then, the density error initialization unit (63) sets an initialization flag (201t) to indicate that the density diagnosis result (201) has been initialized. The density error initialization unit (63) also sets an update flag (201s) to indicate that the density diagnosis result (201) has been updated.

[0164] The density error initialization unit 63 resets the density calibration completion signal 160 and waits until the next density calibration process is performed, and also sets the density diagnosis completion signal 210.

[0165] (3-2-5. Density error calculation and judgment process) The density error calculation and determination process by the density error calculation and determination unit (64) of the density error diagnostic unit (61) will be described with reference to Fig. 10. Fig. 10 is a diagram showing an example of density error diagnostic process 3 according to the embodiment. As shown in Fig. 10, the density error calculation and determination unit (64) has a density error calculation unit (65), a density error comparator 1 (66), a coefficient selector (67), and density error comparators 2 (68a, 68b, 68c).

[0166] The density error calculation unit (65) calculates the density diagnosis result (201) from the change in the density measurement coefficient as shown below. That is, the density error calculation unit (65) calculates the density variation Δρ (201c) using the above-mentioned equation (27), calculates the density error Δρ0 (201d) using the above-mentioned equation (29), calculates the coefficient change rate aCd (201e) using the above-mentioned equation (31), and calculates the coefficient change rate afa (201f) using the above-mentioned equation (32).

[0167] The density error comparator 1 (66) compares the absolute value of the density fluctuation Δρ (201c) with the density fluctuation allowable value (202d) using the above-mentioned equation (28). At this time, if the absolute value of the density fluctuation Δρ (201c) is greater than the density fluctuation allowable value (202d), the density error comparator 1 (66) sets the coefficient selection signal (205). On the other hand, if the absolute value of the density fluctuation Δρ (201c) is equal to or smaller than the density fluctuation allowable value (202d), the density error comparator 1 (66) resets the coefficient selection signal (205).

[0168] The coefficient selector (67) determines whether the coefficient selection signal (205) is set, and if the coefficient selection signal (205) is set, sets the density calibration result (151) to the parameter (28). That is, the coefficient selector (67) assigns the value of the calibration date and time (151x) to the density calibration date and time (28n), assigns the value of the drive time (151y) to the density calibration drive time (28o), assigns the value of the integrated flow rate (151z) to the density calibration integrated flow rate (28p), assigns the value of the density measurement coefficient Cdc (151a) to the density measurement coefficient Cd (28k), and assigns the value of the density measurement coefficient fac (151b) to the density measurement coefficient fa (28l).

[0169] The density error comparators 2 (68a, 68b, 68c) execute the following processes. That is, the density error comparator 2 (68a) compares the change in the density error Δρ0 (201d) with the density error warning value (202h) and sets the density error abnormality (201h) using the above-mentioned equation (30). The density error comparator 2 (68b) compares the change in the coefficient change rate aCd (201e) with the coefficient change rate aCd allowable value (202i) and sets the coefficient change rate aCd abnormality (201i) using the above-mentioned equation (33). The density error comparator 2 (68c) compares the change in the coefficient change rate afa (201f) with the coefficient change rate afa allowable value (202j) and sets the coefficient change rate afa abnormality (201j) using the above-mentioned equation (34).

[0170] The density error initialization unit (63) resets the initialization flag (201t) to indicate that initialization has not been performed. The density error initialization unit (63) also sets the update flag (201s) to indicate that the density diagnosis result (201) has been updated. The density error initialization unit (63) also resets the density calibration completion signal (160) and waits until the next execution of the density calibration process. The density error initialization unit (63) also sets the density diagnosis completion signal (210).

[0171] (3-3. Thickness and stiffness diagnostic processing) 11 to 16 and equations, the thickness diagnosis process executed by the thickness stiffness diagnosis unit (70) of the diagnosis device (2) according to the embodiment will be described. In the following, after explaining the theoretical equation of the thickness stiffness diagnosis process, the whole thickness stiffness diagnosis process, the initialization determination process, the thickness stiffness diagnosis initialization process, the thickness stiffness calculation process, the thickness stiffness change initialization process, and the thickness stiffness change determination process will be described in this order, and finally, the thickness stiffness diagnosis process using the density calibration result (151) will be described.

[0172] (3-3-1. Theoretical formula for thickness and stiffness diagnosis processing) The theoretical formula for the thickness and stiffness diagnostic process is explained below. First, consider a vibration tube with a circular cross section, outer diameter D, and inner diameter d. If the density of the vibration tube is ρu, the length of the vibration tube is lu, and the number of vibration tubes is m, the mass Mu of the vibration tube itself is expressed by the following formula (35).

[0173]

number

[0174] The wall thickness t of the vibration tube is given by the following equation (36).

[0175]

number

[0176] The internal volume V of the vibrating tube is given by the following equation (37).

[0177]

number

[0178] When the coefficient Cd is calculated from the above-mentioned formula (11), the following formula (38) is obtained.

[0179]

number

[0180] In the above formula (38), the first term Cda is a term that depends on the mass and internal volume of the vibration tube, and depends on the cross-sectional shape and material. The second term Cdb is a term that depends on the mass Mu of the accessory and the internal volume of the vibration tube. In other words, the heavier the accessory, the larger Cd becomes.

[0181] In a Coriolis mass flowmeter (1), the amplitude becomes larger toward the tip, the kinetic energy varies depending on the distance from the fixed point, and the farther the mass is located, the greater the impact on the vibration. In order to discuss this accurately, it is necessary to consider the equivalent mass. In the above equation (38), the first term Cda of the coefficient Cd is not affected by position as long as the shape of the vibrating tube does not change. Also, the second term Cdb is affected by position. The vibrating tube length lu and the mass Md of the accessories are values ​​that take into account the equivalent mass.

[0182] Consider a case where the inner diameter d of the oscillating tube increases uniformly due to corrosion or other reasons to become an inner diameter dc. The coefficient Cdc after the change is expressed by the following equation (39).

[0183]

number

[0184] If the vibration conditions of the Coriolis mass flowmeter (1) do not change, there is no change in the equivalent mass, and there is no change in the vibration tube length lu and the mass Md of the accessories.

[0185] The relationship between the coefficient Cdc and the stiffness Kc after the change is given by the following equation (40): Let fac be the frequency when a material with density ρa is measured.

[0186]

number

[0187] The internal volume Vc of the vibrating tube is calculated from the inner diameter dc using the following equation (41).

[0188]

number

[0189] If the inner diameter changes, the measurement error can be eliminated by performing calibration again and updating the coefficient Cdc and frequency fac.

[0190] The inner diameter dc (301c) of the vibration tube (11) after the change is calculated from the above formulas (38) and (39), as shown in formula (42) below. The density measurement coefficient Cd in the initial state is set as the initial coefficient Cd0 (302a). The inner diameter dc of the vibration tube (11) in the initial state is set as the initial inner diameter d0 (302c). The vibration tube density ρu (303b) is assumed to remain unchanged. The inner diameter dc (301c) of the vibration tube (11) after the change is calculated from the density measurement coefficient Cdc (151a) after the change and the initial coefficient Cd0 (302a), as shown in formula (42) below.

[0191]

number

[0192] The wall thickness tc (301d) of the vibration pipe (11) is calculated by the following formula (43).

[0193]

number

[0194] The change in thickness dt (301e) is expressed by the following formula (44).

[0195]

number

[0196] The wall thickness change rate rt (301f) is given by the following formula (45). If there is no change, the wall thickness change rate rt (301f) will be 1. It is also possible to subtract 1 and calculate only the amount of change.

[0197]

number

[0198] The density measurement coefficient fa in the initial state is set as the initial coefficient fa0 (302b). The stiffness change rate aK of the vibration tube (11) from the initial state can be calculated by the following equation (46) from the above equations (14) and (40). Stiffness K0 indicates the initial stiffness. The stiffness change rate aK is 1 if there is no change. It is also possible to subtract 1 and calculate only the change. The stiffness change rate aK is expressed as stiffness change rate aK (301g).

[0199]

number

[0200] Here, by using the inner diameter d of the vibration tube (11) at the time of the previous calibration, the change from the previous calibration can be calculated.

[0201] A thickness and rigidity diagnosis is performed from changes in thickness and rigidity. It is determined whether the absolute value of the difference between the inner diameter dc (301c) of the oscillating pipe (11) and the initial inner diameter d0 (302c) is greater than the inner diameter tolerance (302k). The coefficient dclim indicates the inner diameter tolerance (302k). If it is greater, an inner diameter abnormality (301k) is set. It is also possible to determine upper and lower limits for the judgment. In this case, the conditional formula is the following formula (47).

[0202]

number

[0203] It is judged whether the absolute value of the difference between the wall thickness tc (301d) of the vibration pipe (11) and the initial wall thickness is larger than the wall thickness tolerance (302l). The coefficient tclim indicates the wall thickness tolerance (302l). If it is larger, a wall thickness abnormality (301l) is set. It is also possible to determine upper and lower limits for judgment. In this case, the condition formula is the following formula (48).

[0204]

number

[0205] It is judged whether the absolute value of the thickness change dt (301e) is larger than the thickness change tolerance (302m). The coefficient dtlim indicates the thickness change tolerance (302m). If it is larger, a thickness change abnormality (301m) is set. It is also possible to determine upper and lower limits for judgment. In this case, the condition formula is the following formula (49).

[0206]

number

[0207] It is determined whether the thickness change rate rt (301f) is greater than the thickness change rate tolerance (302n). The coefficient rtlim indicates the thickness change rate tolerance (302n). If it is greater, a thickness change rate abnormality (301n) is set. If there is no change, the thickness change rate rt (301f) becomes the value 1.0. It is also possible to determine upper and lower limits for the judgment. In this case, the condition formula is the following formula (50).

[0208]

number

[0209] It is determined whether the stiffness change rate aK (301g) is greater than the stiffness change rate tolerance (302o). The coefficient aKlim indicates the stiffness change rate tolerance (302o). If it is greater, a stiffness change rate abnormality (301o) is set. If there is no change, the stiffness change rate aK (301g) becomes the value 1.0. It is also possible to determine upper and lower limits for the judgment. In this case, the condition formula is the following formula (51).

[0210]

number

[0211] Corrosion can be judged from the changes in thickness and rigidity. Several of the seven parameters obtained above are used. An example of a judgment formula using the thickness change rate rt (301f) and rigidity change rate aK (301g) is shown in the following formula (52). When corrosion occurs, the thickness change rate rt (301f) becomes smaller than 1. The rigidity change rate aK (301g) becomes smaller than 1.

[0212]

number

[0213] At this time, the judgment value rtcor and the judgment value aKcor are set as the corrosion judgment value (302p).

[0214] Adhesion can be determined from changes in thickness and rigidity. If the thickness increases without a change in rigidity, adhesion is likely. If there is adhesion inside the vibrating tube, the volume of the adhered area is replaced by the adhesion from the measured fluid. Because the adhesion is heavier than air, the density measurement coefficient fac (151b) decreases by the mass, and the density measurement coefficient Cdc (151a) increases. If the tube is filled with fluid, it is affected by the density difference between the fluid and the adhesion. If a soft substance adheres, there is no effect on rigidity.

[0215] Among the seven parameters obtained above, several are used. Here, an example of a judgment formula using the coefficient change rate aCd (201e) and the coefficient change rate afa (201f) is shown in the following formula (53).

[0216]

number

[0217] At this time, the judgment value aCdad and the judgment value afaad are set as the adhesion judgment value (302q).

[0218] The theoretical formula described above is for a tube with a circular cross section, but the formula can also be developed for tubes with an elliptical or rectangular cross section.

[0219] (3-3-2. Overall processing of thickness and stiffness diagnosis) The entire thickness stiffness diagnosis process will be described with reference to Fig. 11. Fig. 11 is a diagram showing an example of the entire thickness stiffness diagnosis process according to the embodiment. The configuration of the thickness stiffness diagnosis unit (70) of the diagnosis device (2) will be described below.

[0220] 11, the thickness / rigidity diagnosis unit (70) is a part of the diagnosis control unit (60), and after executing density error diagnosis processing, performs diagnosis of thickness and rigidity using the density diagnosis result (201) obtained from the density error diagnosis unit (61). The thickness / rigidity diagnosis unit (70) also has an initialization determination unit (71), a thickness / rigidity diagnosis initialization unit (72), a thickness / rigidity calculation unit (73), a thickness / rigidity change initialization unit (74), and a thickness / rigidity change determination unit (75), which respectively execute initialization determination processing, thickness / rigidity diagnosis initialization processing, thickness / rigidity calculation processing, thickness / rigidity change initialization processing, and thickness / rigidity change determination processing.

[0221] The thickness stiffness diagnosis unit (70) executes processing when the density diagnosis completion signal (210) is set. The thickness stiffness diagnosis unit (70) resets the density diagnosis completion signal (210) when processing is completed, and waits for the next density calibration to be performed. The thickness stiffness diagnosis unit (70) also sets the thickness stiffness diagnosis completion signal (310). Here, the thickness stiffness diagnosis completion signal (310) indicates that the thickness stiffness diagnosis unit (70) has been performed. The flow rate error diagnosis simple correction unit (80), which will be described later, uses the stiffness and thickness changes obtained by the thickness stiffness diagnosis unit (70). By setting the thickness stiffness diagnosis completion signal (310), the flow rate error diagnosis simple correction unit (80) executes processing.

[0222] The initialization determination unit (71) determines the process to be executed based on the thickness stiffness diagnosis set value (302) and the density diagnosis completion signal (210), and sets the initialization signal (306), diagnosis initialization signal (307), or diagnosis execution signal (308). At the first execution, the initialization determination unit (71) sets the initialization signal (306), and executes the thickness stiffness diagnosis initialization process. When it is necessary to reset the reference data, the initialization determination unit (71) sets the diagnosis initialization signal (307), and executes the thickness stiffness calculation process and the thickness stiffness change initialization process. At the time of normal diagnosis, the initialization determination unit (71) sets the diagnosis execution signal (308), and executes the thickness stiffness calculation process and the thickness stiffness change determination process.

[0223] The wall thickness stiffness diagnosis initialization unit (72) executes initialization processing of related parameters. The wall thickness stiffness diagnosis initialization unit (72) executes initialization processing only when an initialization signal (306) is set. The wall thickness stiffness diagnosis initialization unit (72) initializes the wall thickness stiffness diagnosis set value (302) and the wall thickness stiffness diagnosis result (301) based on the vibration pipe design value (303) and the density diagnosis result (201). In addition, the wall thickness stiffness diagnosis initialization unit (72) sets the wall thickness stiffness diagnosis completion signal (310) and resets the density diagnosis completion signal (210).

[0224] The thickness stiffness calculation unit (73) executes a process of calculating a thickness stiffness change rate and outputting it to a thickness stiffness diagnosis result (301). At this time, the thickness stiffness calculation unit (73) uses the density diagnosis result (201), the thickness stiffness diagnosis set value (302), and the vibration pipe design value (303). In addition, the thickness stiffness calculation unit (73) executes the process when a diagnosis initialization signal (307) or a diagnosis execution signal (308) is set.

[0225] The thickness stiffness change initialization unit (74) executes a process of resetting an initial value. The thickness stiffness change initialization unit (74) sets the thickness stiffness diagnosis result (301) obtained by the thickness stiffness calculation unit (73) to an initial value. The thickness stiffness change initialization unit (74) executes a process when the diagnosis initialization signal (307) is set. The thickness stiffness change initialization unit (74) initializes the thickness stiffness diagnosis set value (302) and the thickness stiffness diagnosis result (301) based on the thickness stiffness diagnosis result (301), the density diagnosis result (201), and the thickness stiffness diagnosis set value (302). In addition, the thickness stiffness change initialization unit (74) sets the thickness stiffness diagnosis completion signal (310) and resets the density diagnosis completion signal (210).

[0226] The thickness stiffness change determination unit (75) executes a process of setting a thickness stiffness diagnosis result (301). At this time, the thickness stiffness change initialization unit (74) uses the thickness stiffness diagnosis result (301) and the thickness stiffness diagnosis set value (302). The thickness stiffness change initialization unit (74) executes the process only when the diagnosis execution signal (308) is set. In addition, the thickness stiffness change initialization unit (74) sets a thickness stiffness diagnosis completion signal (310) and resets the density diagnosis completion signal (210).

[0227] As described above, the thickness / rigidity diagnostic unit 70 can execute diagnostic processes for changes in thickness and rigidity, or can execute only one of them.

[0228] (3-3-3. Initialization Judgment Process) The initialization determination process by the initialization determination unit (71) of the thickness stiffness diagnosis unit (70) will be described with reference to FIG. 12. FIG. 12 is a diagram showing an example of thickness stiffness diagnosis process 1 according to the embodiment. As shown in FIG. 12, the initialization determination unit (71) executes the process when the density diagnosis completion signal (210) is set. The initialization determination unit (71) also outputs an initialization signal (306), a diagnosis initialization signal (307), and a diagnosis execution signal (308) based on the initial inner diameter d0 (302c), the initial date and time (302x), and the initialization execution command (302u) as the thickness stiffness diagnosis set value (302). The flow of the initialization determination process will be described later in [5. Flow of each process of the calibration device (3) and the diagnosis device (2)].

[0229] (3-3-4. Thickness and stiffness diagnosis initialization process) The wall thickness diagnosis initialization process performed by the wall thickness stiffness diagnosis initialization unit (72) of the wall thickness stiffness diagnosis unit (70) will be described with reference to Fig. 13. Fig. 13 is a diagram showing an example of the wall thickness stiffness diagnosis process 2 according to the embodiment. As shown in Fig. 13, the wall thickness stiffness diagnosis initialization unit (72) has a wall thickness calculation unit (76).

[0230] The wall thickness rigidity diagnosis initialization unit (72) sets an initial value to the wall thickness rigidity diagnosis set value (302) as shown below. That is, it substitutes the value of the density measurement coefficient Cd (201a) into the initial coefficient Cd0 (302a), the value of the density measurement coefficient fa (201b) into the initial coefficient fa0 (302b), the value of the diagnosis date and time (201x) into the initial date and time (302x), the value of the drive time (201y) into the initial drive time (302y), and the value of the integrated flow rate (201z) into the initial integrated flow rate (302z). In addition, the wall thickness rigidity diagnosis initialization unit (72) substitutes the value of the vibration pipe inner diameter d (303c) into the initial inner diameter d0 (302c). Here, the wall thickness is not changed at the first time. In addition, the wall thickness rigidity diagnosis initialization unit (72) resets the initialization execution command (302u).

[0231] The wall thickness / rigidity diagnosis initialization unit (72) initializes the wall thickness / rigidity diagnosis result (301) as shown below. That is, it substitutes the value of the diagnosis date and time (201x) for the diagnosis date and time (301x), substitutes the value of the drive time (201y) for the drive time (301y), substitutes the value of the integrated flow rate (201z) for the integrated flow rate (301z), and sets the vibration tube inner diameter d (303c) to the inner diameter dc (301c). The wall thickness / rigidity diagnosis initialization unit (72) also calculates the initial wall thickness by the wall thickness calculation unit (76) and sets it to the wall thickness tc (301d). The wall thickness / rigidity diagnosis initialization unit (72) also substitutes the vibration tube inner diameter d (303c) and the vibration tube outer diameter D (303a) into the above-mentioned formula (36) to obtain the wall thickness t and substitutes it for the wall thickness tc (301d). Further, the thickness stiffness diagnosis initialization unit (72) sets the thickness change dt (301e) to a value of 0.0, sets the thickness change rate rt (301f) to a value of 0.0, sets the stiffness change rate aK (301g) to a value of 1.0, resets the inner diameter abnormality (301k), resets the thickness abnormality (301l), resets the thickness change abnormality (301m), resets the thickness change rate abnormality (301n), resets the stiffness change rate abnormality (301o), resets the corrosion abnormality (301p), and resets the adhesion abnormality (301q). Furthermore, the thickness stiffness diagnosis initialization unit (72) sets an initialization flag (301t) to indicate that the thickness stiffness diagnosis result (301) has been initialized. Furthermore, the thickness stiffness diagnosis initialization unit (72) sets an update flag (301s) to indicate that the thickness stiffness diagnosis result (301) has been updated.

[0232] The density diagnosis completion signal (210) is reset, and the process waits until the next execution of the density error diagnosis process. The wall thickness stiffness diagnosis initialization unit (72) also sets the wall thickness stiffness diagnosis completion signal (310) to indicate that the wall thickness stiffness diagnosis process has ended.

[0233] (3-3-5. Thickness and stiffness calculation processing) The thickness and stiffness calculation process by the thickness and stiffness calculation unit (73) of the thickness and stiffness diagnosis unit (70) will be described with reference to Fig. 14. Fig. 14 is a diagram showing an example of the thickness diagnosis process 3 according to the embodiment. As shown in Fig. 14, the thickness and stiffness calculation unit (73) has a thickness calculation unit (77) and a stiffness calculation unit (78).

[0234] The thickness and stiffness calculation unit (73) calculates the thickness change rate by the thickness calculation unit (77) as shown below. That is, the thickness calculation unit (77) calculates the thickness and stiffness diagnosis result (301) by using the above-mentioned formulas (42) to (45). At this time, the thickness calculation unit (77) uses the density diagnosis result (201), the thickness and stiffness diagnosis set value (302), and the vibration pipe design value (303) to calculate the inside diameter dc (301c), the thickness tc (301d), the thickness change dt (301e), and the thickness change rate rt (301f). Note that the thickness calculation unit (77) can calculate only a part of the above-mentioned thickness and stiffness diagnosis results (301).

[0235] The thickness / rigidity calculation unit (73) calculates the stiffness change rate by the stiffness calculation unit (78) as shown below. That is, the thickness calculation unit (77) calculates the stiffness change rate aK (301g) by using the above-mentioned formula (46). At this time, the thickness / rigidity calculation unit (73) uses the density diagnosis result (201), the thickness / rigidity diagnosis set value (302), and the vibration pipe design value (303).

[0236] The thickness / rigidity calculation unit (73) sets the diagnosis information of the thickness / rigidity diagnosis result (301) as follows: That is, the thickness / rigidity calculation unit (73) substitutes the value of the diagnosis date / time (201x) for the diagnosis date / time (301x), the value of the drive time (201y) for the drive time (301y), and the value of the integrated flow rate (201z) for the integrated flow rate (301z).

[0237] (3-3-6. Initialization process for thickness and stiffness changes) The thickness stiffness change initialization process performed by the thickness stiffness change initialization unit (74) of the thickness stiffness diagnosis unit (70) will be described with reference to Fig. 15. Fig. 15 is a diagram showing an example of thickness stiffness diagnosis process 4 according to the embodiment.

[0238] The thickness stiffness change initialization unit (74) sets the initial value of the thickness stiffness diagnosis set value (302) as shown below. That is, the thickness stiffness change initialization unit (74) assigns the value of the density measurement coefficient Cd (201a) to the initial coefficient Cd0 (302a), the value of the density measurement coefficient fa (201b) to the initial coefficient fa0 (302b), the value of the diagnosis date and time (201x) to the initial date and time (302x), the value of the drive time (201y) to the initial drive time (302y), the value of the integrated flow rate (201z) to the initial integrated flow rate (302z), and the value of the inner diameter dc (301c) to the initial inner diameter d0 (302c). The thickness stiffness change initialization unit (74) also resets the initialization execution command (302u).

[0239] The thickness / rigidity change initialization unit (74) initializes the thickness / rigidity diagnosis result (301) as shown below. That is, the thickness / rigidity change initialization unit (74) assigns the value of the diagnosis date and time (201x) to the diagnosis date and time (301x), assigns the value of the drive time (201y) to the drive time (301y), assigns the value of the integrated flow rate (201z) to the integrated flow rate (301z), sets a numerical value of 0.0 to the thickness change dt (301e), sets a numerical value of 1.0 to the thickness change rate rt (301f), sets a numerical value of 1.0 to the rigidity change rate aK (301g), resets the inner diameter abnormality (301k), resets the thickness abnormality (301l), resets the thickness change abnormality (301m), resets the thickness change rate abnormality (301n), resets the rigidity change rate abnormality (301o), resets the corrosion abnormality (301p), and resets the adhesion abnormality (301q).

[0240] The thickness stiffness change initialization unit (74) sets an initialization flag (301t) to indicate that the thickness stiffness diagnosis result (301) has been initialized. It also sets an update flag (301s) to indicate that the thickness stiffness diagnosis result (301) has been updated. The thickness stiffness change initialization unit (74) also resets the density diagnosis completion signal (210) and waits until the density error diagnosis process is executed next time. The thickness stiffness change initialization unit (74) also sets a thickness stiffness diagnosis completion signal (310) to indicate that the thickness stiffness diagnosis process has been completed.

[0241] (3-3-7. Thickness and stiffness change determination process) The thickness stiffness change determination process by the thickness stiffness change determination unit (75) of the thickness stiffness diagnosis unit (70) will be described with reference to Fig. 16. Fig. 16 is a diagram showing an example of the thickness stiffness diagnosis process 5 according to the embodiment. As shown in Fig. 16, the thickness stiffness change determination unit (75) has an abnormality determination unit (79).

[0242] The thickness stiffness change determination unit (75), as described below, uses the abnormality determination function (79) to compare the thickness stiffness diagnosis result (301) and the density diagnosis result (201) with the thickness stiffness diagnosis set value (302), set diagnostic abnormality information in the thickness stiffness diagnosis result (301), and determine a diagnostic abnormality. That is, the thickness stiffness change determination unit (75) compares the thickness stiffness change rate of the thickness stiffness diagnosis result (301), the coefficient change rate of the density diagnosis result (201), and the allowable value of the thickness stiffness diagnosis set value (302) to determine an abnormality.

[0243] The thickness / rigidity change determination unit (75) compares the inside diameter dc (301c) with the inside diameter allowable value (302k) using the above-mentioned formula (47). If it is outside the allowable value, the thickness / rigidity change determination unit (75) sets the inside diameter abnormality (301k). On the other hand, if it is within the allowable value, the thickness / rigidity change determination unit (75) resets the inside diameter abnormality (301k). In the case of corrosion, the inside diameter dc (301c) becomes large.

[0244] The thickness / rigidity change determination unit (75) also compares the thickness tc (301d) with the thickness tolerance (302l) using the above-mentioned formula (48). If the thickness tc is outside the tolerance, the thickness / rigidity change determination unit (75) sets the thickness abnormality (301l). On the other hand, if the thickness tc is within the tolerance, the thickness / rigidity change determination unit (75) resets the thickness abnormality (301l). In the case of corrosion, the thickness tc (301d) becomes smaller.

[0245] Furthermore, the thickness / rigidity change determination unit (75) compares the thickness change dt (301e) with the thickness change allowable value (302m) using the above-mentioned formula (49). If the thickness change dt is outside the allowable value, the thickness / rigidity change determination unit (75) sets the thickness change abnormality (301m). On the other hand, if the thickness change is within the allowable value, the thickness / rigidity change determination unit (75) resets the thickness change abnormality (301m). In the case of corrosion, the thickness change dt (301e) becomes negative.

[0246] The thickness / rigidity change determination unit (75) also compares the thickness change rate rt (301f) with the thickness change rate allowable value (302n) using the above-mentioned formula (50). If the thickness change rate rt is outside the allowable value, the thickness / rigidity change determination unit (75) sets a thickness change rate abnormality (301n). On the other hand, if the thickness change rate is within the allowable value, the thickness / rigidity change determination unit (75) resets the thickness change rate abnormality (301n). In the case of corrosion, the thickness change rate rt (301f) becomes smaller than 1.

[0247] Furthermore, the thickness-rigidity change determination unit (75) compares the rigidity change rate aK (301g) with the rigidity change rate allowable value (302o) using the above-mentioned formula (51). If the rigidity change rate is outside the allowable value, the thickness-rigidity change determination unit (75) sets the rigidity change rate abnormality (301o). On the other hand, if the rigidity change rate is within the allowable value, the thickness-rigidity change determination unit (75) resets the rigidity change rate abnormality (301o). In the case of corrosion, the rigidity change rate aK (301g) becomes smaller than 1.

[0248] Furthermore, the thickness / rigidity change determination unit (75) performs a corrosion determination. At this time, if the above-mentioned formula (52) is satisfied, the thickness / rigidity change determination unit (75) sets the corrosion abnormality (301p). On the other hand, if the above-mentioned formula (52) is not satisfied, the thickness / rigidity change determination unit (75) resets the corrosion abnormality (301p).

[0249] The thickness / rigidity change determination unit (75) also performs adhesion determination. At this time, if the above-mentioned formula (53) is satisfied, the thickness / rigidity change determination unit (75) sets the adhesion abnormality (301q). On the other hand, if the above-mentioned formula (53) is not satisfied, the adhesion abnormality (301q) is reset.

[0250] The thickness-based stiffness change determination unit 75 resets the initialization flag 301t to indicate that the thickness-based stiffness diagnosis result 301 has not been initialized, and sets the update flag 301s to indicate that the thickness-based stiffness diagnosis result 301 has been updated.

[0251] The thickness / rigidity change determination unit 75 resets the density diagnosis completion signal 210 and waits until the next execution of the density error diagnosis process. The thickness / rigidity change determination unit 75 also sets the thickness / rigidity diagnosis completion signal 310 to indicate that the thickness / rigidity diagnosis process has ended.

[0252] (3-3-8. Thickness and stiffness diagnosis process using density calibration result (151)) As described above, the thickness stiffness diagnosis unit (70) generates the thickness stiffness diagnosis result (301) using the density diagnosis result (201) generated by the density error diagnosis unit (61). On the other hand, the thickness stiffness diagnosis unit (70) can also generate the thickness stiffness diagnosis result using the density calibration result (151). The thickness stiffness diagnosis process that does not involve the density error diagnosis process will be described below.

[0253] The thickness / rigidity diagnosis unit 70 acquires a density measurement coefficient Cdc (151a) which is a density calibration result 151, instead of the density measurement coefficient Cd (201a) which is a density diagnosis result 201. Also, the thickness / rigidity diagnosis unit 70 acquires a density measurement coefficient fac (151b) which is a density calibration result 151, instead of the density measurement coefficient fa (201b) which is a density diagnosis result 201.

[0254] The thickness stiffness diagnosis unit (70) calculates the coefficient change rate aCd by using the initial coefficient Cd0 (302a) and the density measurement coefficient Cdc (151a), which is the density calibration result (151), instead of the coefficient change rate aCd (201e), which is the density diagnosis result (201) calculated as the ratio between the initial coefficient Cd0 (202a) and the density measurement coefficient Cdc (151a) and the initial value.

[0255] The thickness stiffness diagnosis unit (70) calculates the coefficient change rate afa by using the initial coefficient fa0 (302b) and the density measurement coefficient fac (151b), which is the density calibration result (151), instead of the coefficient change rate afa (201f), which is the density diagnosis result (201) calculated as the ratio of the initial coefficient Cd0 (202a) and the density measurement coefficient Cdc (151a) to an initial value.

[0256] The thickness / rigidity diagnosis unit (70) acquires the calibration date / time (151x), which is the density calibration result (151), instead of the diagnosis date / time (201x), which is the density diagnosis result (201). Moreover, the thickness / rigidity diagnosis unit (70) acquires the drive time (151y), which is the density calibration result (151), instead of the drive time (201y), which is the density diagnosis result (201). Moreover, the thickness / rigidity diagnosis unit (70) acquires the integrated flow rate (151z), which is the density calibration result (151), instead of the integrated flow rate (201z), which is the density diagnosis result (201).

[0257] The thickness / rigidity diagnosis unit (70) generates a density calibration completion signal 2 (161) in parallel with the density calibration completion signal (160) instead of the density diagnosis completion signal (210).

[0258] (3-4. Flow rate error diagnosis and simple correction process) 17 to 21 and equations, the flow rate error diagnosis and simple correction process executed by the flow rate error diagnosis simple correction unit (80) of the diagnosis device (2) according to the embodiment will be described. Below, after explaining the theoretical equation of the flow rate error diagnosis and simple correction process, the overall flow rate error diagnosis and simple correction process, the initialization determination process, the flow rate initialization process, the rigidity thickness initialization process, and the flow rate correction coefficient update process will be described in this order.

[0259] (3-4-1. Theoretical formula for flow rate error diagnosis and simple correction processing) The theoretical formula for flow rate error diagnosis and simple correction processing is explained below. First, the flow rate correction coefficient fk(28u) included in the following equation (54) is calculated from the density calibration result, and the mass flow rate is simply corrected.

[0260]

number

[0261] In the above equation (54), the flow rate measurement coefficient Cq represents the flow rate measurement coefficient Cq (28f), the phase difference θ0 represents the phase difference θ (28d), the frequency f represents the frequency f (28c), the mass flow rate Qmc represents the mass flow rate Qm after simple correction (28a), and the value of the correction coefficient fk represents the flow rate correction coefficient fk (28u).

[0262] The flow rate measurement coefficient Cq in the mass flow rate measurement equation shown above in equation (2) includes the stiffness (spring constant) ks of the torsional vibration of the vibrating tube and the ratio of the resonance frequencies of the bending vibration and torsional vibration. The stiffness change rate measured by diagnostic device (2) is the stiffness in the vibration direction, but is thought to fluctuate similarly to the stiffness of the torsional vibration. Changes in wall thickness are related to changes in the resonance frequency. Simple correction of the mass flow rate is possible by determining the correction coefficient fk from the rate of change obtained by diagnostic device (2).

[0263] In the diagnostic process described above, the rigidity and wall thickness are obtained from the density measurement coefficient Cd and the density measurement coefficient fa. Here, the density measurement coefficient Cd and the density measurement coefficient fa contain information about the vibrating tube. Therefore, by using the density measurement coefficient itself or the rate of change of the density measurement coefficient, simple correction of the mass flow rate is possible.

[0264] The calculation formula for the flow rate correction coefficient fkq using the stiffness change rate aK (301g), wall thickness change rate rt (301f), density measurement coefficient coefficient change rate aCd (201e), and density measurement coefficient coefficient change rate afa (201f) is shown in the following formula (55). Here, a simple correction is performed by substituting the flow rate correction coefficient fkq for the flow rate correction coefficient fk (28u).

[0265]

number

[0266] In the above equation (55), the coefficient Ckx indicates the flow rate correction coefficient Ckx(28v), and is a value that depends on the characteristics of the detection unit (10) of the Coriolis mass flowmeter (1). The correction equation for the flow rate correction coefficient fkq may be an approximate straight line or an approximate curve. It is not necessary to use all the change rates. The parameters and correction coefficients to be used are determined using multiple regression analysis, inference by AI (Artificial Intelligence), etc. The flow rate correction coefficient Ckx(28v) depends on the detector, and is therefore set in advance for each detector. Methods include actually corroding the vibrating tube and calculating the effects of corrosion by simulation.

[0267] In the above equation (55), the wall thickness change rate rt (301f) is used, but the correction equation for the flow rate correction coefficient fkq can also be formed using any of the inside diameter dc (301c), the wall thickness tc (301d), or the wall thickness change dt (301e).

[0268] Note that traditional flow rate calibration requires actual flow of water, etc., and requires separate equipment. Density calibration can be performed by measuring two fluids with known densities, i.e., air and water, and does not require special equipment. Unlike flow rate calibration, which involves flowing a fluid, there is a high possibility of error.

[0269] When mass flow calibration is performed, the error that was corrected using the flow correction coefficient fk (28u) is absorbed by the flow measurement coefficient Cq (28f). Therefore, after mass flow calibration, it is necessary to set the flow correction coefficient fk (28u) to its initial value of 1.0. In equation (55), the flow correction coefficient Ckx (28v) is fixed because it depends on the characteristics of the detection unit (10). Therefore, at the start or when performing mass flow calibration, it is necessary to initialize the rate of change.

[0270] Each rate of change is calculated in the thickness and stiffness diagnosis section 70. Although it is possible to configure the function to perform initialization by issuing an initialization command to the thickness and stiffness diagnosis function 70, the initial values ​​are stored in the flow rate error diagnosis simple correction function 80, and the following formula (56) is shown, which uses the rate of change from the initial values.

[0271]

number

[0272] At this time, as initial values, an initial stiffness change rate aK0 (502g), an initial thickness change rate rt0 (502f), an initial coefficient change rate aCd0 (502a), and an initial coefficient change rate afa0 (502b) are used.

[0273] When calibrating mass flow rate, the flow rate correction coefficient fk (28u) is set to an initial value of 1.0. Mass flow rate calibration and density calibration are not necessarily synchronized. In particular, if the stiffness has changed since the previous density calibration, a flow rate error will occur. Therefore, to minimize errors in the simple correction of the flow rate measurement coefficient, density calibration must be performed at the same time as mass flow rate calibration.

[0274] Changing the flow rate measurement coefficient creates discontinuities in the flow rate measurement results. If the flow rate fluctuations are within the allowable range, there is also the option of prioritizing the continuity of the measurement values. If the flow rate correction coefficient before simple correction is fk and the flow rate correction coefficient after simple correction is fkq, the flow rate fluctuation rate rqd (501c) is defined as the following equation (57). The mass flow rate before simple correction is mass flow rate Qmc, and the mass flow rate after simple correction is mass flow rate Qmcq.

[0275]

number

[0276] The flow rate fluctuation allowable value (502h) is set to rqdlim and compared with the flow rate change rate rqd. By determining whether or not the flow rate correction coefficient fk can be replaced, small fluctuations can be suppressed. In this case, the conditional expression is the following expression (58).

[0277]

number

[0278] It is always replaced when the flow rate fluctuation tolerance ratio value rqdlim is set to 0. When the flow rate correction coefficient fk is not updated, the flow rate correction coefficient fk maintains the value at the time of the previous update.

[0279] Using the flow rate correction coefficient fkq after simple correction, the flow rate error rate rqe (501b) of the mass flow measurement from the time of flow rate calibration is calculated as the following equation (59). The flow rate error rate rqe (501b) is used as a basis for diagnosing the flow rate error. The mass flow rate at the time of flow rate calibration is defined as the mass flow rate Qm.

[0280]

number

[0281] The flow rate error rate rqe (501b) is compared with the flow rate error alarm value rqelim, and if the fluctuation becomes large, a flow rate diagnosis abnormality (501r) is set. The flow rate error alarm value rqelim indicates the flow rate error alarm value (502r). At this time, the condition formula is the following formula (60).

[0282]

number

[0283] By setting the flow rate diagnosis abnormality (501r), it is possible to inform the user of an abnormality in the device. In addition, it is also possible to display the flow rate error rate rqe on the display operation unit (30) or an external device (31) and input whether or not the coefficient should be updated.

[0284] The flow rate error diagnosis and simple correction process described above includes a diagnosis process that monitors the flow rate error and issues an alarm, and a simple correction process that updates the flow rate correction coefficient fkq to reduce the density error, and it is possible to use only one of them.

[0285] (3-4-2. Flow error diagnosis and simple correction process) The overall flow rate error diagnosis and simple correction process will be described with reference to Fig. 17. Fig. 17 is a diagram showing an example of the overall flow rate error diagnosis and simple correction process according to the embodiment. The configuration of the flow rate error diagnosis simple correction unit (80) of the diagnosis device (2) will be described below.

[0286] 17, the flow rate error diagnosis simple correction unit (80) is a part of the diagnosis control unit (60). The flow rate error diagnosis simple correction unit (80) also has an initialization determination unit (81), a flow rate initialization unit (82), a rigidity thickness initialization unit (83), and a flow rate correction coefficient update unit (84), which respectively execute an initialization determination process, a flow rate initialization process, a rigidity thickness initialization process, and a flow rate correction coefficient update process.

[0287] The flow rate error diagnosis simple correction unit (80) executes processing when the thickness / rigidity diagnosis completion signal (310) or the flow rate calibration completion signal (120) is set. The flow rate error diagnosis simple correction unit (80) also updates the flow rate diagnosis result (501) and updates the parameters (28) based on the thickness / rigidity diagnosis result (301) and the density diagnosis result (201).

[0288] The initialization determination unit (81) sets an initialization execution signal 1 (507), an initialization execution signal 2 (508), or an update execution signal (509). The initialization determination unit (81) makes a determination based on the flow calibration completion signal (120), the thickness / rigidity diagnosis result (301), the thickness / rigidity diagnosis completion signal (310), and the flow diagnosis set value (502).

[0289] The flow rate initialization unit (82) sets the parameters (28), the flow rate diagnosis result (501), and the flow rate diagnosis set value (502) from the parameters (28), the density diagnosis result (201), and the thickness / rigidity diagnosis result (301), and resets the flow rate calibration completion signal (120). The flow rate initialization unit (82) executes initialization processing when the mass flow rate calibration processing is executed. In addition, the flow rate initialization unit (82) executes processing when the initialization execution signal 1 (507) is set.

[0290] The rigidity / thickness initialization unit (83) sets the parameters (28), the flow rate diagnosis result (501) and the flow rate diagnosis set value (502) from the density diagnosis result (201) and the thickness / rigidity diagnosis result (301), and resets the thickness / rigidity diagnosis completion signal (310). The rigidity / thickness initialization unit (83) executes initialization processing when the thickness / rigidity diagnosis unit (70) is executed. The rigidity / thickness initialization unit (83) also executes processing when an initialization execution signal 2 (508) is set.

[0291] The flow rate correction coefficient update unit (84) sets the parameters (28) and the flow rate diagnosis result (501) from the parameters (28), the density diagnosis result (201), the thickness / rigidity diagnosis result (301), and the flow rate diagnosis set value (502), and resets the thickness / rigidity diagnosis completion signal (310). Moreover, the flow rate correction coefficient update unit (84) executes processing when the update execution signal (509) is set.

[0292] (3-4-3. Initialization Judgment Process) The initialization determination process will be described with reference to FIG. 18. The initialization determination process by the initialization determination unit (81) of the flow rate error diagnosis simple correction unit (80) will be described. FIG. 18 is a diagram showing an example of the flow rate error diagnosis simple correction process 1 according to the embodiment. As shown in FIG. 18, the initialization determination unit (81) executes the process when the flow rate calibration completion signal (120) or the thickness stiffness diagnosis completion signal (310) is set. The initialization determination unit (81) also outputs an initialization execution signal 1 (507), an initialization execution signal 2 (508), and an update execution signal (509) based on the initialization flag (301t) as the thickness stiffness diagnosis result (301) and the initial date and time (502x) and the initialization execution command (502u) as the flow rate diagnosis set value (502). The flow of the initialization determination process will be described later in [5. Flow of each process of the calibration device (3) and the diagnosis device (2)].

[0293] (3-4-4. Flow rate initialization process) The density flow rate initialization process by the flow rate initialization unit (82) of the flow rate error diagnosis simple correction unit (80) will be described with reference to Fig. 19. Fig. 19 is a diagram showing an example of the flow rate error diagnosis and simple correction process 3 according to the embodiment. As shown in Fig. 19, the flow rate initialization unit (82) has a rigidity / thickness selection unit (85).

[0294] The flow rate initialization unit (82) initializes the flow rate diagnosis set value (502) by the rigidity / thickness selection unit (85) as described below. That is, the flow rate initialization unit (82) selects the initial value of the change rate. At this time, if the diagnosis date and time (301x) has not been set, the flow rate initialization unit (82) sets the initial coefficient change rate aCd0 (502a), the initial coefficient change rate afa0 (502b), the initial thickness change rate rt0 (502f), and the initial rigidity change rate aK0 (502g) to a value of 1.0. On the other hand, when the diagnosis date and time (301x) is set, the flow rate initialization unit (82) assigns the value of the coefficient change rate aCd (201e) to the initial coefficient change rate aCd0 (502a), assigns the value of the coefficient change rate afa (201f) to the initial coefficient change rate afa0 (502b), assigns the value of the thickness change rate rt (301f) to the initial thickness change rate rt0 (502f), assigns the value of the stiffness change rate aK (301g) to the initial stiffness change rate aK0 (502g), assigns the value of the flow calibration date and time (28h) to the initial date and time (502x), assigns the value of the flow calibration drive time (28i) to the initial drive time (502y), and assigns the value of the flow calibration integrated flow rate (28j) to the initial integrated flow rate (502z). The flow rate initialization unit 82 also sets an initialization execution command 502u to perform initialization at the next density calibration, and sets the flow rate correction coefficient fk 28u to an initial value of 1.0.

[0295] The flow rate initialization unit (82) initializes the flow rate diagnosis result (501) as follows. That is, the flow rate initialization unit (82) assigns a value of 1.0 to the flow rate correction coefficient fkq (501a), assigns a value of 0.0 to the flow rate error rate rqe (501b), assigns a value of 0.0 to the flow rate fluctuation rate rqd (501c), assigns the value of the flow rate calibration date and time (28h) to the correction date and time (501x), assigns the value of the flow rate calibration drive time (28i) to the drive time (501y), and assigns the value of the flow rate calibration integrated flow rate (28j) to the integrated flow rate (501z). The flow rate initialization unit (82) also resets the flow rate diagnosis abnormality (501r). The flow rate initialization unit (82) also sets an initialization flag (501t) to indicate that the flow rate diagnosis result (501) has been initialized. The flow rate initialization unit 82 also sets an update flag 501s to indicate that the flow rate diagnosis result 501 has been updated, and resets a flow rate calibration completion signal 120 to wait for the next execution of the flow rate calibration process.

[0296] (3-4-5. Initialization of rigidity and thickness) The rigidity thickness initialization process by the rigidity thickness initialization unit (83) of the flow rate error diagnosis simple correction unit (80) will be described with reference to Fig. 20. Fig. 20 is a diagram showing an example of flow rate error diagnosis and simple correction process 3 according to the embodiment.

[0297] The rigidity thickness initialization unit (83) initializes the flow rate diagnosis set value (502) as follows: That is, the rigidity thickness initialization unit (83) assigns the value of the coefficient change rate aCd (201e) to the initial coefficient change rate aCd0 (502a), assigns the value of the coefficient change rate afa (201f) to the initial coefficient change rate afa0 (502b), assigns the value of the thickness change rate rt (301f) to the initial thickness change rate rt0 (502f), assigns the value of the rigidity change rate aK (301g) to the initial rigidity change rate aK0 (502g), assigns the value of the diagnosis date and time (301x) to the initial date and time (502x), assigns the value of the drive time (301y) to the initial drive time (502y), and assigns the value of the integrated flow rate (301z) to the initial integrated flow rate (502z). The rigidity / thickness initialization unit 83 also resets the initialization execution command 502u and waits for an external initialization command, and sets the flow rate correction coefficient fk 28u to an initial value of 1.0.

[0298] The rigid thickness initialization unit (83) initializes the flow rate diagnosis result (501) as shown below. That is, the rigid thickness initialization unit (83) assigns a value of 1.0 to the flow rate correction coefficient fkq (501a), assigns a value of 0.0 to the flow rate error rate rqe (501b), assigns a value of 0.0 to the flow rate fluctuation rate rqd (501c), assigns the value of the diagnosis date and time (301x) to the correction date and time (501x), assigns the value of the drive time (301y) to the drive time (501y), and assigns the value of the integrated flow rate (301z) to the integrated flow rate (501z). The rigid thickness initialization unit (83) also resets the flow rate diagnosis abnormality (501r). The rigid thickness initialization unit (83) also sets an initialization flag (501t) to indicate that the flow rate diagnosis result (501) has been initialized. The stiffness / thickness initialization unit 83 also sets an update flag 501s to indicate that the flow rate diagnosis result 501 has been updated, and resets a stiffness / thickness diagnosis completion signal 310 to wait for the next execution of the stiffness / thickness diagnosis process.

[0299] (3-4-6. Flow rate correction coefficient update process) The flow rate correction coefficient updating process by the flow rate correction coefficient updating unit (84) of the flow rate error diagnosis simple correction unit (80) will be described with reference to Fig. 21. Fig. 21 is a diagram showing an example of flow rate error diagnosis and simple correction process 4 according to the embodiment. As shown in Fig. 21, the flow rate correction coefficient calculation unit (86), a flow rate fluctuation comparator 1 (87), a flow rate correction coefficient setter (88), and a flow rate fluctuation comparator 2 (89) are provided.

[0300] The flow rate correction coefficient updating unit (84) calculates a flow rate correction coefficient, a flow rate error rate, and a flow rate fluctuation rate using a flow rate correction coefficient calculation unit (86). That is, the flow rate correction coefficient updating unit (84) calculates a flow rate correction coefficient fkq using the above-mentioned equation (56) and substitutes it for the flow rate correction coefficient fkq (501a). The flow rate correction coefficient updating unit (84) also calculates a flow rate fluctuation rate rqd using the above-mentioned equation (57) and substitutes it for the flow rate fluctuation rate rqd (501c). The flow rate correction coefficient updating unit (84) also calculates a flow rate error rate rqe using the above-mentioned equation (59) and substitutes it for the flow rate error rate rqe (501b).

[0301] The flow rate correction coefficient update unit (84) sets the flow rate diagnosis result (501) as follows: That is, the flow rate correction coefficient update unit (84) assigns the value of the diagnosis date and time (301x) to the correction date and time (501x), assigns the value of the drive time (301y) to the drive time (501y), and assigns the value of the integrated flow rate (301z) to the integrated flow rate (501z).

[0302] The flow rate correction coefficient updating unit (84) uses the flow rate fluctuation comparator 1 (87) to compare the absolute value of the flow rate fluctuation rate rqd (501c) with the flow rate fluctuation allowable value (502h). At this time, the flow rate correction coefficient updating unit (84) makes a determination using the above-mentioned equation (58). If the absolute value of the flow rate fluctuation rate rqd (501c) is greater than the flow rate fluctuation allowable value (502h), the flow rate correction coefficient updating unit (84) sets the flow coefficient selection signal (504) and sets the value of the flow rate correction coefficient fkq (501a) to the flow rate correction coefficient fk (28u) using the flow rate correction coefficient setter (88).

[0303] The flow rate correction coefficient updating unit (84) executes the following process using the flow rate fluctuation comparator 2 (89). That is, the flow rate correction coefficient updating unit (84) compares the flow rate error rate rqe (501b) with the flow rate error warning value (502r) using the above-mentioned equation (60). At this time, if the absolute value of the flow rate error rate rqe (501b) is greater than the flow rate error warning value (502r), the flow rate correction coefficient updating unit (84) sets a flow rate diagnosis abnormality (501r). On the other hand, if the absolute value of the flow rate error rate rqe (501b) is equal to or less than the flow rate error warning value (502r), the flow rate correction coefficient updating unit (84) resets the flow rate diagnosis abnormality (501r). In addition, the flow rate correction coefficient updating unit (84) resets the initialization flag (501t), indicating that the flow rate diagnosis result (501) has not been initialized. In addition, the stiffness / thickness initialization unit 83 sets the update flag 501s to indicate that the flow rate diagnosis result 501 has been updated. Furthermore, the flow rate correction coefficient update unit 84 resets the thickness / stiffness diagnosis completion signal 310 and waits for the next execution of the thickness / stiffness diagnosis process.

[0304] (3-5. Timing prediction diagnostic processing) 22 to 26 and equations, a timing prediction diagnostic process executed by the timing prediction diagnostic unit (90) of the diagnostic device (2) according to the embodiment will be described. Below, a theoretical equation for the timing prediction diagnostic process will be described, followed by a description of the entire timing prediction diagnostic process, timing prediction diagnostic process using the calibration diagnostic result, timing prediction diagnostic process using the density diagnostic result, timing prediction diagnostic process using the thickness-rigidity diagnostic result, and timing prediction diagnostic process using the flow rate diagnostic result.

[0305] (3-5-1. Theoretical formula for timing prediction diagnostic processing) The theoretical formula for the timing prediction diagnosis process will be explained below. Here, an example of the wall thickness change dt (301e) is shown as an example of the formula used in the timing prediction diagnosis. Similar formulas can also be made for other diagnosis values. Here, the coefficient change rate aCd (201e), coefficient change rate afa (201f), inner diameter dc (301c), wall thickness tc (301d), wall thickness change rate rt (301f), stiffness change rate aK (301g), density error Δρ0 (201d), flow rate correction coefficient fkq (501a), and flow rate error rate rqe (501b) are taken as the coefficient change rate aCd (201e), coefficient change rate afa (201f), inner diameter dc (301c), wall thickness tc (301d), wall thickness change rate rt (301f), stiffness change rate aK (301g), density error Δρ0 (201d), flow rate correction coefficient fkq (501a), and flow rate error rate rqe (501b).

[0306] Here, the changes are approximated using an approximate straight line or curve from multiple data points, and timing prediction diagnosis is performed. The parameters and correction coefficients used are determined using multiple regression analysis, AI inference, etc. Using the maximum rate of change from multiple data allows predictions to be made under the conditions where the change is greatest.

[0307] Here, an example is shown in which an approximation line is created from the diagnosis results of two points and timing prediction diagnosis is performed. If the coefficient x is the history information number, x=1 is the start, x=2 is the present, the date and time is Tmx, the driving time is Tdx, the integrated flow rate is Qmx, and the change in thickness is dtx, the approximation line is created as shown in the following equations (61) to (63).

[0308]

number

[0309]

number

[0310]

number

[0311] In the above formula (61), the coefficient am indicates the change in thickness per date and time. Moreover, the coefficient bm indicates the change in thickness at x=0. In the above formula (62), the coefficient ad indicates the change in thickness per drive time. Moreover, the coefficient bd indicates the change in thickness at x=0. In the above formula (63), the coefficient aq indicates the change in thickness per integrated flow rate. Moreover, the coefficient bq indicates the change in thickness at x=0. Here, from the above formulas (61) to (63), the following formulas (64) to (69) are obtained.

[0312]

number

[0313]

number

[0314]

number

[0315]

number

[0316]

number

[0317]

number

[0318] Here, a diagnosis target value dts of the wall thickness change is set. A predicted value that reaches the diagnosis target value dts is obtained. If the predicted value is expressed by the date and time Tme, the driving time Tde, and the mass flow rate Qme, the following formulas (70) to (72) are obtained.

[0319]

number

[0320]

number

[0321]

number

[0322] The flow rate correction coefficient fk (28u) indicates the flow rate error that has occurred. By inputting the flow rate correction coefficient fk (28u) into the flow rate measurement formula, the flow rate error can be corrected, but since the flow rate correction coefficient fk (28u) is an estimate, it contains a certain amount of error. By using the flow rate correction coefficient fk (28u) to perform timing prediction diagnosis, it is possible to predict the date and time, operating time, and mass flow rate when the error limit value will be reached.

[0323] (3-5-2. Overall processing of timing prediction diagnosis) The entire timing prediction diagnosis process will be described with reference to Fig. 22. Fig. 22 is a diagram showing an example of the entire timing prediction diagnosis process according to the embodiment. The configuration of the timing prediction diagnosis unit (90) of the diagnosis device (2) will be described below.

[0324] The timing prediction diagnosis unit (90) has a history unit (91), a change trend calculation unit (92), and a prediction unit (93), and predicts timing from any one of the results of the density calibration unit (51), the density error diagnosis unit (61), the thickness rigidity diagnosis unit (70), and the flow rate error diagnosis simple correction unit (80).

[0325] First, the timing prediction diagnosis unit (90) determines whether an update flag is set. Here, the timing prediction diagnosis unit (90) checks the update flag of the diagnosis data included in the result of each diagnosis. That is, the timing prediction diagnosis unit (90) checks the update flag (151s) included in the density calibration result (151) which is the calibration result of the density calibration unit (51), checks the update flag (301s) included in the thickness stiffness diagnosis result (301) which is the diagnosis result of the thickness stiffness diagnosis unit (70), checks the update flag (201s) included in the density diagnosis result (201) which is the diagnosis result of the density error diagnosis unit (61), and checks the update flag (501s) included in the flow rate diagnosis result (501) which is the correction result of the flow rate error diagnosis simple correction unit (80). If none of the above update flags is set, the timing prediction diagnosis unit (90) ends the process.

[0326] Next, the timing prediction diagnosis unit (90) stores the above diagnosis result by using the history unit (91). Subsequently, the timing prediction diagnosis unit (90) calculates a change trend value (601) from the updated data in the history unit (91) by using the change trend calculation unit (92). At this time, the timing prediction diagnosis unit (90) approximates the change by the approximation line or approximation curve shown in the above-mentioned equations (64) to (69). Note that the timing prediction diagnosis unit (90) determines the parameters and correction coefficients to be used by using multiple regression analysis, AI inference, etc.

[0327] Then, the timing prediction diagnosis unit (90) calculates a predicted value from the change trend value (601) and the diagnosis target value (602) using the prediction unit (93), and outputs the calculated value as a timing prediction diagnosis result (603). At this time, the timing prediction diagnosis unit (90) performs the calculations shown in the above-mentioned equations (70) to (72). The timing prediction diagnosis unit (90) transmits the calculated timing prediction diagnosis result (603) to the display operation unit (30) of the Coriolis mass flowmeter (1) or the external device (31). Finally, the timing prediction diagnosis unit (90) resets the update flag.

[0328] (3-5-3. Timing prediction diagnostic processing using density calibration results) A timing prediction diagnostic process using the density calibration result will be described with reference to Fig. 23. Fig. 23 is a diagram showing an example of a timing prediction diagnostic process 1 according to the embodiment.

[0329] The timing prediction diagnosis unit (90) performs timing prediction diagnosis from the density calibration result (151) of the density calibration unit (51) as described below. That is, the timing prediction diagnosis unit (90) executes timing prediction diagnosis processing when the update flag (151s) included in the density calibration result (151) is set. At this time, the history unit (91) of the timing prediction diagnosis unit (90) imports data using the setting of the update flag (151s) as a trigger. The history unit (91) can also select necessary data from the input data. Here, the density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) are important parameters for timing prediction. The history unit (91) resets the update flag (151s) when the import is completed.

[0330] (3-5-4. Timing prediction diagnosis processing using density diagnosis results) A timing prediction diagnostic process using the density diagnosis result will be described with reference to Fig. 24. Fig. 24 is a diagram showing an example of timing prediction diagnostic process 2 according to the embodiment.

[0331] The timing prediction diagnostic unit (90) performs timing prediction diagnosis from the density diagnosis result (201) of the density error diagnostic unit (61) as described below. That is, the timing prediction diagnostic unit (90) executes timing prediction diagnosis processing when the update flag (201s) included in the density diagnosis result (201) is set. At this time, the history unit (91) of the timing prediction diagnostic unit (90) imports data in response to the setting of the update flag (201s). The history unit (91) can also select necessary data from the input data. Here, the density error Δρ0 (201d), the coefficient change rate aCd (201e), and the coefficient change rate afa (201f) are important parameters for timing prediction. The history unit (91) resets the update flag (201s) when the import is completed.

[0332] (3-5-5. Timing prediction diagnosis process using thickness and stiffness diagnosis results) The timing prediction diagnostic process using the wall thickness stiffness diagnosis result will be described with reference to Fig. 25. Fig. 25 is a diagram showing an example of timing prediction diagnostic process 3 according to the embodiment.

[0333] The timing prediction diagnosis unit (90) performs timing prediction diagnosis from the thickness / rigidity diagnosis result (301) of the thickness / rigidity diagnosis unit (70) as described below. That is, the timing prediction diagnosis unit (90) executes timing prediction diagnosis processing when the update flag (301s) included in the thickness / rigidity diagnosis result (301) is set. At this time, the history unit (91) of the timing prediction diagnosis unit (90) imports data using the setting of the update flag (301s) as a trigger. The history unit (91) can also select necessary data from the input data. Here, the inside diameter dc (301c), the thickness tc (301d), the thickness change rate rt (301f), and the rigidity change rate aK (301g) are important parameters for timing prediction. When the import is completed, the history unit (91) resets the update flag (301s).

[0334] (3-5-6. Timing prediction diagnostic process using flow rate diagnostic results) A timing prediction diagnostic process using a flow rate diagnosis result will be described with reference to Fig. 26. Fig. 26 is a diagram showing an example of timing prediction diagnostic process 4 according to the embodiment.

[0335] The timing prediction diagnosis unit (90) performs timing prediction diagnosis from the flow rate diagnosis result (501) of the flow rate error diagnosis simple correction unit (80) as described below. That is, the timing prediction diagnosis unit (90) executes timing prediction diagnosis processing when the update flag (501s) included in the flow rate diagnosis result (501) is set. The history unit (91) of the timing prediction diagnosis unit (90) imports data when the update flag (501s) is set. The history unit (91) is also capable of selecting necessary data from the input data. Here, the flow rate correction coefficient fkq (501a) and the flow rate error rate rqe (501b) are important parameters for timing prediction. The history unit (91) resets the update flag (501s) when the import is completed.

[0336] [4. Processing results of each process of the diagnostic device (2)] 27 to 37, the results of each process of the diagnosis device (2) according to the embodiment and their effects will be described. The density diagnosis result, thickness rigidity diagnosis result, flow rate diagnosis result, and timing prediction diagnosis result will be described in this order.

[0337] (4-1. Density diagnosis results and effects) The density diagnosis result and the effect will be described with reference to Fig. 27. Fig. 27 is a diagram showing an example of the density diagnosis result according to the embodiment. In the following, the density diagnosis result will be described, and then the effect of the density diagnosis process will be described.

[0338] (4-1-1. Density diagnosis results) The density diagnosis result will be described with reference to Fig. 27. The density diagnosis result shows the result of flowing a corrosive fluid into a Coriolis mass flowmeter (1), performing density calibration before and after corrosion, and measuring the stiffness change using the method described in Patent Document 1 together with the density calibration.

[0339] Figure 27(1) shows the measurement data. Test# is the number of tests, with 0 indicating before corrosion. Density calibration was performed before corrosion and after the corrosive fluid was allowed to flow for a certain period of time. The Test# value indicates the number of corrosions. The amount of corrosion increases as the Test# value increases. Density calibration was performed with air and water. No pressure was applied. The values ​​f1s and f2s indicate the frequency f (28c) obtained in the measurement. The values ​​T1s and T2s indicate the temperature T (28e) during the measurement. The value f1 indicates the corrected frequency f1 (154) obtained by correcting the frequency f1s by the temperature T1s. The value f2 indicates the corrected frequency f2 (155) obtained by correcting the frequency f2s by the temperature T2s. The density ρ1 (158) and density ρ2 (159) indicate the density of air and the density of water at standard conditions, obtained using the temperatures T1s and T2s.

[0340] FIG. 27(2) shows the density calibration result (151) and the density diagnosis result (201). The density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) were calculated by substituting the measured values ​​in FIG. 27(1) into the above-mentioned formulas (21) to (24). The density fluctuation Δρ (201c) was calculated from the above-mentioned formula (27). The density of air and water was used as the measurement target density ρt (202c). Also, the density fluctuation that occurred after the previous density calibration is shown. The density error Δρ0 (201d) was calculated from the above-mentioned formula (29). The density of air and water was used as the measurement target density ρt (202c). Also, the density error from the initial state is shown. The density fluctuation Δρ (201c) is compared with the density fluctuation tolerance value (202d) by the above-mentioned formula (28), and the fluctuation is evaluated, and the replacement of the density measurement coefficient can be determined. Furthermore, the density error Δρ0 (201d) can be compared with the density error warning value (202h) by the above-mentioned equation (30) to set a density error abnormality (201h).

[0341] Figure 27(3) shows the change in density measurement coefficient fac (151b) and density measurement coefficient Cdc (151a) depending on the number of corrosions. Both decrease as the amount of corrosion increases.

[0342] FIG. 27(4) shows the change in density error Δρ0 (201d) depending on the number of corrosions. The densities of air and water were used as the density ρt (202c) of the measurement object. The density variation Δρ (201c) increases as the amount of corrosion increases. The density error Δρ0 (201d) changes depending on the setting of the density ρt (202c) of the measurement object. Since the corrosive fluid is flowed to forcibly cause corrosion, the density error Δρ0 (201d) changes significantly. In this way, by density calibration, the density error Δρ0 (201d) can be estimated as the density diagnosis result (201) according to the embodiment, and by monitoring the density error, the accuracy of the density measurement can be maintained.

[0343] (4-1-2. Effects) As described above, the density error occurring can be estimated from the change in the density measurement coefficient obtained by density calibration. Since the density error depends on the density of the object to be measured, the density error is calculated taking into account the density of the object to be measured. A density error tolerance can be set and an alarm can be issued to notify of an abnormality. The occurrence of a density error indicates that an error has also occurred in the mass flow measurement results. It is also possible to notify that the measurement instrument needs to be readjusted. Density calibration is an important function that determines the accuracy of a Coriolis mass flowmeter and is performed in a stable situation. Therefore, accurate measurements can be made without being affected by disturbances. Changing the density measurement coefficient by density calibration creates discontinuities in the density measurement results. If the density fluctuation is within the tolerance range, there is also the option of prioritizing the continuity of the measurement values. By setting a density fluctuation tolerance, it is possible to determine whether or not the density measurement coefficient can be replaced, and the fluctuation of the density measurement results can be suppressed. Coriolis mass flowmeters are characterized by their ability to perform accurate measurements. Density measurement is one of the basic functions of a Coriolis mass flowmeter, and the target accuracy can be maintained by monitoring the density error.

[0344] (4-2. Thickness and rigidity diagnosis results and effects) The wall thickness stiffness diagnosis results and effects will be described with reference to Fig. 28 to Fig. 32. In the following, wall thickness stiffness diagnosis result 1, wall thickness stiffness diagnosis result 2, and wall thickness stiffness diagnosis result 3 will be described, and then the effects of the wall thickness stiffness diagnosis process will be described.

[0345] (4-2-1. Thickness and rigidity diagnosis result 1) The wall thickness and stiffness diagnosis result 1 will be described with reference to Fig. 28. Fig. 28 is a diagram showing an example of the wall thickness and stiffness diagnosis result 1 according to the embodiment.

[0346] FIG. 28(1) shows the results of calculation using the formula according to the embodiment. Here, the thickness and stiffness diagnosis was performed based on the density calibration results shown in FIG. 27(1) and FIG. 27(2). “Density Calibration” is the result of calculation using the formula according to the embodiment. The amount of change was calculated based on the value of Test #0. The inner diameter dc (301c), thickness tc (301d), thickness change dt (301e), thickness change rate rt (301f), and stiffness change rate aK (301g) were calculated using the above formulas (42) to (46). The changes from the initial Test #0 are also shown. The variable aKc indicates the stiffness change rate aKc measured using the method of Patent Document 1. The value was almost the same as the stiffness change rate aK (301g).

[0347] FIG. 28(2) shows the number of corrosions, the thickness change dt (301e), the thickness change rate rt (301f), the stiffness change rate aK (301g), and the stiffness change rate aKc measured by the method of Patent Document 1. The stiffness change rate aK (301g) according to the embodiment and the stiffness change rate aKc according to Patent Document 1 are the same. The thickness change rate also decreased with the same tendency. In this way, the thickness change rate and stiffness change rate can be estimated as the thickness stiffness diagnosis result (301) according to the embodiment based on the density calibration result.

[0348] (4-2-2. Thickness and rigidity diagnosis result 2) The wall thickness rigidity diagnosis result 2 will be described with reference to Fig. 29 and Fig. 30. Fig. 29 is a diagram for explaining the wall thickness rigidity diagnosis result 2 according to the embodiment. Fig. 30 is a diagram showing an example of the wall thickness rigidity diagnosis result 2 according to the embodiment.

[0349] In the following, a test was carried out to verify the effect of the sensitivity of the upstream sensor (13) as shown in Fig. 29. As shown in Fig. 29, the upstream signal S1 (13a) was attenuated between the detection unit (10) and the conversion unit (20) by an attenuator (13b). This simulated a decrease in the sensitivity of the upstream sensor (13).

[0350] Figure 30 (1) shows the results of density calibration performed by changing the gain of the attenuator (13b). The variation in the density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) was less than 0.01%. The density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) can be obtained regardless of the gain of the attenuator (13b).

[0351] FIG. 30(2) shows the stiffness change rate aK (301g) obtained by density calibration while changing the gain of the damper (13b) and the stiffness change rate aKc obtained by the method of Patent Document 1. The stiffness change rate aK (301g) does not depend on the gain of the damper (13b). The stiffness change rate aKc depends on the gain of the damper (13b). The method of Patent Document 1 interprets that when the sensitivity of the upstream sensor (13) decreases and the upstream signal S1 (13a) becomes small, the vibration pipe (11) has become stiff. The same phenomenon occurs in the downstream sensor (14) and the vibration unit (12).

[0352] The stiffness change rate aK (301g) and the thickness change rate rt (301f) are shown in Fig. 30 (3). They were obtained with a variation of 0.01% or less. In the thickness stiffness processing according to the embodiment, since the amplitude information of the sensor is not used, the stiffness change rate aK (301g) and the thickness change rate rt (301f) can be measured regardless of the change in sensitivity of the sensor (13, 14) or the vibration unit (12).

[0353] (4-2-3. Thickness and rigidity diagnosis result 3) The thickness and stiffness diagnosis result 3 will be described with reference to Fig. 31 and Fig. 32. Fig. 31 and Fig. 32 are diagrams showing an example of the thickness and stiffness diagnosis result 3 according to the embodiment. In the following, a test for verifying the adhesion diagnosis was carried out as the thickness and stiffness diagnosis process.

[0354] Figure 31(1) shows the results of density calibration with a total of 0.978g of vinyl tape attached to the outside of the vibrating tube. "Normal" shows the case without the tape attached, and "Tape" shows the case with the tape attached. The frequency and temperature were measured in air and water for each case. The frequency was corrected and the density was calculated based on the temperature. Each measurement was performed five times.

[0355] Figures 31(2) and 31(3) show the results of determining the density measurement coefficient Cd (28k) and density measurement coefficient fa (28l) from Figure 31(1). The density error Δρ0 (201d) was calculated by assuming the measurement object density ρt (202c) to be air and water. By attaching the tape to the outside, the density measurement coefficient fa decreased and the density measurement coefficient Cd increased. The density error Δρ0 (201d) is in g / l. By attaching the tape to the outside, the density error Δρ0 (201d) increases. This is thought to be due to the increase in weight.

[0356] FIG. 32 shows the thickness diagnosis result. The amount of change was calculated based on the value of Test #1. The inner diameter dc (301c) is the value calculated by the above formula (42), the thickness tc (301d) is the value calculated by the above formula (43), the thickness change dt (301e) is the value calculated by the above formula (44), the thickness change rate rt (301f) is the value calculated by the above formula (45), and the stiffness change rate aK (301g) is the result calculated by the above formula (46). When adhesion occurs, the density measurement coefficient Cd (28k) and the density measurement coefficient fa (28l) fluctuate, so adhesion diagnosis is possible by density calibration.

[0357] (4-2-4. Effects) As described above, in the thickness stiffness diagnosis process according to the embodiment, the thickness and stiffness change rate can be determined individually by using the change in density measurement coefficient obtained by density calibration and the design information of the vibrating tube. Since the thickness information and stiffness change rate can be determined individually, corrosion diagnosis and adhesion diagnosis are possible. Furthermore, instead of judging corrosion from stiffness change, the thickness change is diagnosed directly. A fluctuation tolerance value is set for the thickness information and stiffness change rate, and an abnormality can be notified by issuing an alarm. At this time, the thickness information includes the inner diameter, thickness, thickness change, and thickness change rate, and the allowable value for abnormality judgment is set as a value directly related to the abnormality.

[0358] In addition, in the thickness stiffness diagnostic process according to the embodiment, thickness information and stiffness change rate are obtained using the change in density measurement coefficient obtained by density calibration and design information of the vibration tube, so that new mechanisms such as fixing the drive gain and obtaining a frequency response are not required. In this case, special operations and software for analysis are not required. Also, the diagnostic function can be realized not only by the conversion unit (20) of the Coriolis mass flowmeter (1) but also by the external device (31) or the calibration device (3). Diagnosis is possible along with the calibration of the Coriolis mass flowmeter (1). The soundness of the device is diagnosed by adding a diagnostic procedure after the density calibration procedure.

[0359] In conventional diagnosis based on stiffness change, the amplitude of the sensor signal is used in addition to the frequency. In this case, it is affected by the sensitivity of the sensor, etc. In the thickness stiffness diagnosis process according to the embodiment, since the amplitude information of the sensor is not used, the stiffness change rate and thickness change are estimated individually regardless of the change in sensitivity of the sensor or the vibrating unit or the change in the circuit gain.

[0360] (4-3. Flow rate diagnosis results and effects) The flow rate diagnosis results and effects will be described with reference to Figures 33 to 36. Below, flow rate diagnosis result 1 and flow rate diagnosis result 2 will be described, and then the effects of the flow rate error diagnosis and simple correction process will be described.

[0361] (4-3-1. Flow rate diagnosis result 1) The flow rate diagnosis result 1 will be described with reference to Fig. 33. Fig. 33 is a diagram showing an example of the flow rate diagnosis result 1 according to the embodiment.

[0362] First, consider a situation in which corrosion increases the flow rate error. Corrosion reduces the flow rate measurement coefficient Cq and increases the ratio θ0 / f of the phase difference θ0 and frequency f. An error occurs because the flow rate measurement coefficient Cq (28f) is the value before corrosion.

[0363] Figure 33 shows the relationship between error and simple correction. If the error variation per measurement is -0.1%, then 10 measurements will result in an error of -1.0%. If the initial value of the flow measurement coefficient Cq (28f) is still used, this will result in an error of +1.0% in the 10th flow measurement.

[0364] "Qe=-0.1%" shows the flow rate error when no flow rate calibration is performed. The flow rate error was calculated when the flow rate correction coefficient fk (28u) was updated. "fk=-0.1%" shows the flow rate error when the rate of change of the flow rate correction coefficient fk (28u) is equal to the flow rate error. In this case, the flow rate measurement coefficient Cq (28f) can be corrected by using the flow rate correction coefficient fk (28u). The flow rate error returns to zero by performing density calibration.

[0365] The error when the rate of change of the flow correction coefficient fk (28u) is -0.05% / calibration is shown as "fk=-0.05%". When it is -0.15% / calibration, it is shown as "fk=-0.15%". The error can be suppressed by simple correction. If the allowable error is ±0.5%, without simple correction, the allowable error will be reached after 5 times, but with simple correction, it will be 10 times. This shows that the interval between flow calibrations can be extended by using the flow correction coefficient fk (28u) and performing simple correction of the flow measurement coefficient.

[0366] In this way, by updating the flow rate correction coefficient fk(28u) based on the density calibration result, simple correction of the flow rate is possible.

[0367] (4-3-2. Flow rate diagnosis result 2) The flow rate diagnosis result 2 will be described with reference to Fig. 34 to Fig. 36. Fig. 34 to Fig. 36 are diagrams showing an example of the flow rate diagnosis result 2 according to the embodiment.

[0368] Figure 34(1) shows the rate of change of density measurement coefficient, rate of change of rigidity, rate of change of thickness, and flow rate error when corrosion was repeated multiple times. At the same time as the density calibration experiment in Figure 27(1), water was run and the flow rate error rate Qe was measured. The coefficient change rate aCd and the coefficient change rate afa show the change ratio of the density measurement coefficient obtained in Figure 27(2). The coefficient change rate aCd (201e) shows the rate of change of density measurement coefficient Cdc (151a). The coefficient change rate afa (201f) shows the rate of change of density measurement coefficient fac (151b). The inner diameter change rate rt shows the rate of change of thickness rt (301f) calculated in the thickness rigidity diagnosis in Figure 28(1). The rigidity change rate aK shows the rigidity change rate aK (301g) calculated in the thickness rigidity diagnosis in Figure 28(1). The change in the flow measurement coefficient Cq (28f) was calculated from the flow error rate Qe, and the change rate aCq was obtained.

[0369] Figure 34 (2) shows the relationship between the rate of change of the density measurement coefficient, the rate of change of wall thickness, the rate of change of rigidity, and the change in the flow coefficient Cq. The flow error Qe indicates the error rate when measurement is performed without updating the flow measurement coefficient Cq (28f). If the flow correction coefficient fk (28u) has the same trend as the rate of change aCq, the flow error can be corrected. The trends of the rate of change aCq and each rate of change match, but differences appear as the corrosion increases. The change in the coefficient rate of change afa is small. The change in the flow measurement coefficient Cq (28f) can be easily corrected using at least one of the coefficient rate of change aCd, the rate of change of wall thickness rt, and the rate of change of rigidity aK.

[0370] FIG. 34(3) shows the result of performing the flow error diagnosis simple correction process according to the embodiment using the result of FIG. 34(1). The flow error when simple correction is not performed is shown in Qe. The flow error when simple correction is performed using the stiffness change rate aK (301g), the wall thickness change rate rt (301f), the coefficient change rate aCd (201e), and the coefficient change rate afa (201f) is shown. In the above-mentioned formula (56), one of Ckx (x=1 to 4) is set to 1 and the others are set to 0, and the result is shown in which each change rate is set to the flow correction coefficient fk (28u). Except for the flow error Qe, the results show before and after updating the flow correction coefficient fk (28u). When the coefficient change rate afa (201f) is used, the effect is small. This is because the change in the coefficient change rate afa (201f) is smaller than the change in the flow measurement coefficient Cq (28f). The results using the other three parameters are equivalent. Since the rate of change is larger than that of the flow measurement coefficient Cq (28f), the flow error after simple correction becomes negative with each iteration.

[0371] Figure 34 (4) shows the relationship between the flow measurement coefficient Cq (28f) and the wall thickness change rate rt (301f), stiffness change rate aK (301g), coefficient change rate aCd (201e), and coefficient change rate afa (201f). There is a correlation between all variables. The slope of the coefficient change rate afa (201f) is small.

[0372] Figure 35 (1) shows the results of determining the flow rate correction coefficient Ckx (28v) using multiple regression analysis. A blank indicates that the value is 0. The results show the case where the four parameters are used independently and the case where the correction coefficient is determined by combining the stiffness change rate aK (301g) and the wall thickness change rate rt (301f), the coefficient change rate aCd (201e) and the coefficient change rate afa (201f). The correlation is high in all cases. Although the combination and F value become small, the combination is also effective. The flow rate correction coefficient fk (28u) can be calculated using the coefficient change rate aCd (201e), the wall thickness change rate rt (301f), the stiffness change rate aK (301g) and the wall thickness change rate rt (301f), or the coefficient change rate aCd (201e) and the coefficient change rate afa (201f), allowing for simple correction of the mass flow rate.

[0373] Figure 35(2) shows the flow rate correction result when the flow rate correction coefficient Ckx (28v) in Figure 35(1) is used. By performing density calibration, the error returns to almost zero. By updating the flow rate correction coefficient fk (28u) using the density calibration result, simple correction of the flow rate is possible.

[0374] Figure 36 (1) shows the results of estimating the flow rate error. The flow rate correction coefficient fk (28u) was found from equation (56) above, and the flow rate error rate rqe (501b) was calculated from equation (59) above. One of the four variables was used for the flow rate correction coefficient fk (28u). Shown here is the result rqex1 when the flow rate correction coefficient Ckx (28v) corresponding to the variable used in equation (56) above is set to the value 1.0, and shown is the result rqex2 when the flow rate correction coefficient Ckx (28v) is used using the value found by correlation.

[0375] Figure 36 (2) shows the change in flow rate error Qe and flow rate error rate rqex1. The change in the result when using the coefficient change rate afa (201f) is small. The flow rate error rate rqe (501b) calculated using the stiffness change rate aK (301g), the wall thickness change rate rt (301f) and the coefficient change rate aCd (201e) shows the same change trend as the flow rate error Qe.

[0376] Figure 36 (3) shows the change in the flow rate error Qe and the flow rate error rate rqex2. The change trends of each result matched those of the flow rate error Qe.

[0377] By setting a flow rate error alarm value (502r) for the flow rate error rate rqe (501b), it is possible to determine whether the flow rate diagnosis is abnormal (501r).

[0378] (4-3-3. Effects) As described above, in the flow rate error diagnosis and simple correction process according to the embodiment, the flow rate measurement coefficient and flow rate error can be obtained using the stiffness change rate, thickness change rate, and density measurement coefficient change rate obtained from density calibration, density diagnosis process, and thickness stiffness diagnosis process. Using these, the flow rate measurement coefficient is simply corrected, thereby reducing the flow rate error without flow rate calibration.

[0379] Density calibration can be achieved on-site by measuring frequency and temperature in known fluids such as air and water. Simple correction of flow rate correction coefficients extends the actual calibration interval.

[0380] There is a high correlation between the mass flow rate error and the rate of change of stiffness, wall thickness, and density measurement coefficient, but there is a difference in the slope. By correcting the relationship between the mass flow rate error and each rate of change with an approximate straight line or curve, the error of the simplified correction is reduced. The parameters and correction coefficients used are determined using multiple regression analysis, AI inference, etc.

[0381] The accuracy of the simple correction depends on the measurement accuracy of the parameters used in the correction formula for the flow rate correction coefficient. Since density calibration can be performed in a stable environment, it can be calculated with high accuracy.

[0382] The flow rate error is estimated from the change in the flow rate correction coefficient. A tolerance for the flow rate error is set, and an alarm is issued to notify of an abnormality.

[0383] Changing the flow correction coefficient creates discontinuities in the mass flow measurement results. If the flow rate fluctuation caused by changing the flow correction coefficient is within the tolerance range, there is also the option of prioritizing the continuity of the measurement value. By setting the flow rate fluctuation tolerance, it is possible to determine whether or not to replace the flow correction coefficient and suppress the fluctuation of the mass flow measurement results.

[0384] Coriolis mass flowmeters are characterized by their ability to measure with high accuracy. Mass flow measurement is one of the basic functions of a Coriolis mass flowmeter, and the target accuracy is maintained by monitoring flow rate errors.

[0385] (4-4. Timing prediction diagnosis results) The timing prediction diagnostic result and the effect will be described with reference to Fig. 37. In the following, the timing prediction diagnostic result will be described, and then the effect of the timing prediction diagnostic process will be described.

[0386] (4-4-1. Timing prediction diagnosis results) A calculation example of timing prediction diagnosis is shown in Fig. 37. Fig. 37 is a diagram showing an example of a timing prediction diagnosis result according to the embodiment.

[0387] Two points were assumed for each date and time, drive time, integrated flow rate, and density error. These are shown in "Data 1" and "Data 2". The coefficients of the approximation line obtained from the above-mentioned equations (64) to (69) are shown in "Slope ax" and "Intercept bx". The diagnosis target value dts is set to -0.5 mm. The predicted values ​​obtained from the above-mentioned equations (70) to (72) are shown in "Estimation". "Estimation - Data 2" shows the predicted values ​​from "Data 2". In Figure 37, from "Data 2", the diagnosis target value dts is reached after 8 days, drive time of 60 hours, or an integrated flow rate of 760 t.

[0388] (4-4-2. Effects) As described above, timing prediction diagnosis makes it possible to predict when a failure will occur or when maintenance or equipment replacement will be required. By having a history of calibration and diagnosis, the health of the equipment can be understood. By using the converter's operating time and cumulative flow rate in addition to the time, a diagnosis that is close to reality can be performed. Corrosion occurs when corrosive fluids are flowed, so the cumulative flow rate is important. Converter failures are often affected by the operating time. By evaluating density error and flow rate error, it is possible to predict when flow rate calibration will be necessary. By storing the obtained diagnosis results in a history, the state of condition changes can be understood. This makes timing prediction diagnosis (life diagnosis) possible. From multiple parameters, the parameter that suits the purpose can be used.

[0389] For users, predicting when maintenance or replacement is necessary is important for the effective use of equipment. Maintenance requires the equipment to be shut down and calibration costs are incurred. For equipment prone to failures such as corrosion, replacement must be anticipated.

[0390] [5. Flow of each process of the calibration device (3) and the diagnosis device (2)] 38 to 43, the flow of each process of the calibration device (3) and the diagnosis device (2) according to the embodiment will be described. In the following, after describing the flow of the entire diagnosis process according to the embodiment, the flow of the density calibration process will be described as the flow of the process of the calibration device (3), and the flow of the process of the diagnosis device (2) will be described in the order of the flow of the density error diagnosis process, the flow of the wall thickness stiffness diagnosis process, the flow of the flow rate error diagnosis / simple correction process, and the flow of the timing prediction diagnosis process.

[0391] (5-1. Overall flow of diagnostic processing) The overall flow of the diagnostic process will be described with reference to Fig. 38. Fig. 38 is a flowchart showing an example of the overall flow of the diagnostic process according to the embodiment. Note that the processes of steps S101 to S105 below can also be executed in a different order. Also, some of the processes of steps S101 to S105 below may be omitted.

[0392] First, the calibration device (3) executes density calibration processing (step S101). Next, the diagnosis device (2) executes density error diagnosis processing (step S102), thickness stiffness diagnosis processing (step S103), flow rate error diagnosis and simple correction processing (step S104), timing prediction diagnosis processing (step S105), and ends the processing.

[0393] (5-2. Density calibration process flow) The flow of the entire diagnosis process will be described with reference to FIG. 39. FIG. 39 is a flowchart showing an example of the flow of the entire density calibration process according to the embodiment. Below, the flow of the entire density calibration process will be described, and then the flow of each process will be described. Note that each process below can also be executed in a different order. Also, some of the processes below may be omitted.

[0394] (5-2-1. Overall flow of density calibration process) As shown in FIG. 39, the calibration device (3) executes a density measurement coefficient calculation process (steps S201 to S223), stores the density measurement coefficient in the parameter (28) (step S224), and ends the process.

[0395] (5-2-2. Overall flow of density measurement coefficient calculation process) The calibration device (3) calibrates the density measurement and updates the density measurement coefficient as shown below. First, the frequency is measured for two types of materials with known densities. At this time, the coefficient n (152c) is used to perform two measurements, and the coefficient n (152c) is set to 1 as an initial value (step S201). Next, the calibration device (3) sets the filling state to On in order to determine that the material in the vibration tube has been replaced (step S202). Then, the calibration device (3) determines whether the filling state is On (step S203). At this time, the calibration device (3) waits until the vibration tube (11) is filled with the material n. If the filling state is On (step S203: Yes), the calibration device (3) proceeds to the process of step S204, and if the filling state is not On (step S203: No), the calibration device (3) proceeds to the process of step S206.

[0396] The calibration device (3) fills the vibrating tube (11) with the substance n (step S204). At this time, an external device different from the Coriolis mass flowmeter (1) empties the vibrating tube (11) in the case of air, and in the case of a vacuum, discharges the substance inside using a vacuum pump or the like. Here, the density calibration process requires the density of the substance n, and if the density changes with temperature and pressure, a formula or a mathematical table relating to temperature and pressure is required. Then, the display operation unit (30) or the external device (31) turns off the filling state to indicate that filling has ended (step S205), and the process returns to step S203.

[0397] The calibration device (3) waits until the measured values ​​stabilize, since the temperature and the like become unstable due to the replacement of the substance (step S206). At this time, the calibration device (3) may wait for a fixed period of time, or may monitor fluctuations in the frequency f (28c) and temperature T (28e), or may not wait if the fluctuations do not affect the results. Then, the calibration device (3) acquires the frequency f (28c) and temperature T (28e) (step S207), and proceeds to the processing of step S208.

[0398] The calibration device (3) determines whether the pressure gauge (29) is connected based on the pressure gauge connection signal (28s) (step S208). At this time, if the pressure gauge (29) is connected (step S208: Yes), the calibration device (3) acquires the external input pressure Pin (28r) and sets it as pressure P (28t) (step S210), and proceeds to the process of step S211. On the other hand, if the pressure gauge (29) is not connected (step S208: No), the calibration device (3) sets the default pressure Ps (28q) as pressure P (28t) (step S209), and proceeds to the process of step S211.

[0399] The calibration device (3) corrects the frequency f (28c) with the temperature T (28e) and pressure P (28t) using the frequency correction unit (53) to calculate the corrected frequency fn (153) (step S211). The calibration device (3) also uses the material selection switch (54) to store the corrected frequency fn (153) in the corrected frequency f1 (154) or the corrected frequency f2 (155) according to the coefficient n (152c) (step S212). The calibration device (3) also uses the standard density calculation unit (55) to calculate the standard density ρc (156) of the material n from the temperature T (28e), pressure P (28t) and coefficient n (152c) (step S213), and proceeds to the process of step S214.

[0400] The calibration device (3) uses the density selection switch (56) to determine whether the density ρn (157) is to be manually input by the density selection (152b) (step S214). At this time, if the calibration device (3) determines that the density is to be manually input (step S214: Yes), the calibration device (3) sets the manually input density ρin (152a) set by the display operation unit (30) or the external device (31) as the density ρn (157) (step S215) and proceeds to the process of step S217. On the other hand, if the calibration device (3) determines that the density is not to be manually input (step S214: No), the calibration device (3) sets the standard density ρc (156) as the density ρn (157) (step S216) and proceeds to the process of step S217.

[0401] The calibration device (3) uses the material selection switch (57) to store the density ρn (157) in the density ρ1 (158) or density ρ2 (159) according to the coefficient n (152c) (step S217). The calibration device (3) also sets the coefficient n (152c) to n+1 (step S218). If the coefficient n (152c) is 2 or less (step S219: Yes), the calibration device (3) proceeds to the process of step S208 and measures the second material. On the other hand, if the coefficient n (152c) is greater than 2 (step S219: No), the calibration device (3) uses the density measurement coefficient calculation execution unit (58) to calculate the density measurement coefficient Cdc (151a) and the density measurement coefficient fac (151b) (step S220). At this time, the calibration device (3) calculates the density measurement coefficient by substituting the corrected frequency f1 (154), the corrected frequency f2 (155), the density ρ1 (158), and the density ρ2 (159) into the above-mentioned equations (21) to (24).

[0402] The calibration device (3) saves the date and time, the converter drive time, and the integrated flow rate (step S221). At this time, the calibration device (3) saves the date and time (28x) in the calibration date and time (151x), the converter drive time (28y) in the drive time (151y), and the integrated flow rate (28z) in the integrated flow rate (151z).

[0403] The calibration device (3) sets the update flag (151s) (step S222), sets the density calibration completion signal (160) (step S223), and proceeds to the process of step S224.

[0404] (5-3. Density error diagnosis process flow) The flow of density error diagnosis processing will be described with reference to FIG. 40. FIG. 40 is a flowchart showing an example of the overall flow of density error diagnosis processing according to an embodiment. Below, the overall flow of density error diagnosis processing will be described, and then the flow of each process will be described. Note that the following processes can also be performed in a different order. Also, some of the following processes may be omitted.

[0405] (5-3-1. Overall flow of density error diagnosis process) 40, the diagnostic device (2) executes an initialization determination process (steps S301 to S307), and if the initialization signal (203) is set (step S308: Yes), executes a density error initialization process (step S309), and ends the process. On the other hand, if the initialization signal (203) is not set (step S308: No), the diagnostic device (2) proceeds to the process of step S310.

[0406] If the calculation determination signal (204) is set (step S310: Yes), the diagnostic device (2) executes density error calculation determination processing (step S311) and ends the processing. On the other hand, if the calculation determination signal (204) is not set (step S310: No), the diagnostic device (2) ends the processing.

[0407] (5-3-2. Flow of initialization determination process) As shown in FIG. 40, after the calibration device (3) performs density calibration processing (step S301) of the density measurement coefficient, the diagnostic device (2) selects the processing to be performed based on the density calibration completion signal (160) and the density diagnosis setting value (202).

[0408] The diagnostic device (2) resets the initialization signal (203) and the calculation determination signal (204) (step S302). Next, the diagnostic device (2) determines whether the density calibration completion signal (160) is set (step S303). At this time, if the density calibration completion signal (160) is set (step S303: Yes), the diagnostic device (2) proceeds to the process of step S304. On the other hand, if the density calibration completion signal (160) is not set (step S303: No), the diagnostic device (2) ends the process.

[0409] The diagnostic device (2) determines whether the initialization execution command (202u) is set (S304). At this time, if the initialization execution command (202u) is set (step S304: Yes), the diagnostic device (2) sets the initialization signal (203) (step S305) and proceeds to processing of step S308 and thereafter. On the other hand, if the initialization execution command (202u) is not set (step S304: No), the diagnostic device (2) proceeds to processing of step S305.

[0410] The diagnostic device (2) determines whether an initial value exists (step S305). If there is no initial value (step S305: Yes), the diagnostic device (2) sets the initialization signal (203) (step S306) and proceeds to processing from step S308 onwards. On the other hand, if there is an initial value (step S305: No), the diagnostic device (2) sets the calculation determination signal (204) (step S307) and proceeds to processing from step S308 onwards. Here, the diagnostic device (2) determines that there is no initial value when any of the following applies: the initial coefficient Cd0 (202a) is 0, the initial coefficient fa0 (202b) is 0, or the initial date and time (202x) has not been set.

[0411] (5-3-3. Density error initialization process flow) The diagnostic device (2) saves the density calibration result (151) in the parameter (28), sets the initial value of the density diagnosis set value (202), resets the initialization execution command (202u), initializes the density diagnosis result (201), sets the initialization flag (201t), sets the update flag (201s), resets the density calibration completion signal (160), sets the density diagnosis completion signal (210), and ends the process.

[0412] (5-3-4. Density error calculation and judgment process flow) The diagnostic device (2) calculates density variation Δρ (201c), density error Δρ0 (201d), coefficient change rate aCd (201e), and coefficient change rate afa (201f) as a density diagnostic result (201) from the change in the density measurement coefficient. At this time, the diagnostic device (2) sets the coefficient selection signal (205) if the absolute value of the density variation Δρ (201c) is greater than the density variation allowable value (202d). On the other hand, the diagnostic device (2) resets the coefficient selection signal (205) if the absolute value of the density variation Δρ (201c) is equal to or less than the density variation allowable value (202d).

[0413] The diagnostic device (2) judges whether the coefficient selection signal (205) is set. If the coefficient selection signal (205) is set, the diagnostic device (2) sets the density calibration result (151) in the parameter (28). On the other hand, if the coefficient selection signal (205) is set, the diagnostic device (2) proceeds to the next process.

[0414] The diagnostic device (2) sets the measurement coefficient and the measurement information in the density diagnostic result (201). The diagnostic device (2) also compares the change in the density error Δρ0 (201d) with the density error warning value (202h) and sets a density error abnormality (201h), compares the change in the coefficient change rate aCd (201e) with the coefficient change rate aCd allowable value (202i) and sets a coefficient change rate aCd abnormality (201i), and compares the change in the coefficient change rate afa (201f) with the coefficient change rate afa allowable value (202j) and sets a coefficient change rate afa abnormality (201j).

[0415] The diagnostic device (2) resets the initialization flag (201t), sets the update flag (201s), resets the density calibration completion signal (160), sets the density diagnosis completion signal (210), and ends the process.

[0416] (5-4. Flow of wall thickness and stiffness diagnosis process) The flow of the thickness stiffness diagnosis process will be described with reference to FIG. 41. FIG. 41 is a flowchart showing an example of the flow of the entire thickness stiffness diagnosis process according to the embodiment. Below, the flow of the entire thickness stiffness diagnosis process will be described, and then the flow of each process will be described. Note that each of the processes below can also be executed in a different order. Also, some of the processes below may be omitted.

[0417] (5-4-1. Overall flow of thickness and stiffness diagnosis process) 41, the diagnostic device (2) executes an initialization determination process (steps S401 to S407), and if the initialization signal (306) is set (step S408: Yes), executes a thickness stiffness diagnosis initialization process (step S409), and ends the process. On the other hand, if the initialization signal (306) is not set (step S408: No), the diagnostic device (2) proceeds to the process of step S410.

[0418] If the diagnosis initialization signal (307) is set (step S410: Yes), the diagnosis device (2) executes a thickness stiffness calculation process (step S411), executes a thickness stiffness change initialization process (step S412), and ends the process. On the other hand, if the diagnosis initialization signal (307) is not set (step S410: No), the diagnosis device (2) proceeds to the process of step S413.

[0419] If the diagnosis execution signal (308) is set (step S413: Yes), the diagnosis device (2) executes a thickness stiffness calculation process (step S414), executes a thickness stiffness change determination process (step S415), and ends the process. On the other hand, if the diagnosis execution signal (308) is not set (step S413: No), the diagnosis device (2) ends the process.

[0420] (5-4-2. Flow of initialization determination process) As shown in Fig. 41, first, the diagnostic device (2) resets the initialization signal (306), the diagnosis initialization signal (307), and the diagnosis execution signal (308) (step S401). Next, the diagnostic device (2) judges whether the density diagnosis completion signal (210) is set (step S402). At this time, if the density diagnosis completion signal (210) is set (step S402: Yes), the diagnostic device (2) proceeds to the process of step S403, and if the density diagnosis completion signal (210) is not set (step S402: No), the diagnostic device (2) ends the process.

[0421] The diagnostic device (2) determines whether an initial value exists (step S403). At this time, if there is no initial value (step S403: Yes), the diagnostic device (2) sets an initialization signal (306) (step S404). On the other hand, if there is an initial value (step S403: No), the diagnostic device (2) proceeds to the process of step S405. Here, the diagnostic device (2) determines that there is no initial value when either the initial inner diameter d0 (302c) is the numerical value 0 or the initial date and time (302x) has not been set.

[0422] The diagnostic device (2) determines whether the initialization execution command (302u) is set (step S405). At this time, if the initialization execution command (302u) is set (step S405: Yes), the diagnostic device (2) sets the diagnostic initialization signal (307) (step S406) and proceeds to the processing of step S408 and thereafter. On the other hand, if the initialization execution command (302u) is not set (step S405: No), the diagnostic device (2) sets the diagnostic execution signal (308) (step S407) and proceeds to the processing of step S408 and thereafter.

[0423] (5-4-3. Flow of wall thickness and stiffness diagnosis initialization process) The diagnostic device (2) sets an initial value to the thickness stiffness diagnosis setting value (302), resets the initialization execution command (302u), initializes the thickness stiffness diagnosis result (301), sets the initialization flag (301t), sets the update flag (301s), resets the density diagnosis completion signal (210), sets the thickness stiffness diagnosis completion signal (310), and ends the process.

[0424] (5-4-4. Flow of thickness and stiffness calculation process) The diagnostic device (2) calculates the thickness change rate, calculates the stiffness change rate, sets the diagnostic information of the thickness stiffness diagnostic result (301), and ends the process.

[0425] (5-4-5. Flow of Initialization Process for Thickness and Stiffness Change) The diagnostic device (2) sets an initial value of the thickness stiffness diagnosis set value (302), resets the initialization execution command (302u), initializes the thickness stiffness diagnosis result (301), sets the initialization flag (301t), sets the update flag (301s), resets the density diagnosis completion signal (210), sets the thickness stiffness diagnosis completion signal (310), and ends the process.

[0426] (5-4-6. Flow of thickness stiffness change judgment process) The diagnostic device (2) compares the wall thickness stiffness diagnosis result (301) and the density diagnosis result (201) with the wall thickness stiffness diagnosis set value (302), sets diagnostic abnormality information in the wall thickness stiffness diagnosis result (301), resets the initialization flag (301t), sets the update flag (301s), resets the density diagnosis completion signal (210), sets the wall thickness stiffness diagnosis completion signal (310), and ends the process.

[0427] (5-5. Flow rate error diagnosis and simple correction process flow) The flow of the flow error diagnosis and simple correction process will be described with reference to FIG. 42. FIG. 42 is a flowchart showing an example of the overall flow of the flow error diagnosis and simple correction process according to the embodiment. Below, the overall flow of the flow error diagnosis and simple correction process will be described, and then the flow of each process will be described. Note that each of the processes below can also be executed in a different order. Also, some of the processes below may be omitted.

[0428] (5-5-1. Overall flow of flow rate error diagnosis and simple correction process) 42, first, the diagnostic device (2) executes an initialization determination process (steps S501 to S509), and if the initialization execution signal 1 (507) is set (step S510: Yes), it executes a flow rate initialization process (step S511) and ends the process. On the other hand, if the initialization execution signal 1 (507) is not set (step S510: No), the diagnostic device (2) proceeds to the process of step S512.

[0429] If the initialization execution signal 2 (508) is set (step S512: Yes), the diagnostic device (2) executes the rigidity / thickness initialization process (step S513) and ends the process. On the other hand, if the initialization execution signal 2 (508) is not set (step S512: No), the diagnostic device (2) proceeds to the process of step S514.

[0430] If the update execution signal (509) is set (step S514: Yes), the diagnostic device (2) executes the flow rate correction coefficient update process (step S515) and ends the process. On the other hand, if the update execution signal (509) is not set (step S514: No), the diagnostic device (2) ends the process.

[0431] (5-5-2. Flow of initialization determination process) As shown in FIG. 42, first, the diagnostic device (2) resets the initialization execution signal 1 (507), the initialization execution signal 2 (508), and the update execution signal (509) (step S501). Next, the diagnostic device (2) determines whether the flow rate calibration completion signal (120) is set (step S502). Here, the flow rate calibration completion signal (120) is set when the mass flow rate calibration process is executed by the mass flow rate calibration unit (41) of the calibration device (3). At this time, if the flow rate calibration completion signal (120) is set (step S502: Yes), the diagnostic device (2) sets the initialization execution signal 1 (507) (step S503) and proceeds to the process of step S510 and after. On the other hand, if the flow rate calibration completion signal (120) is not set (step S502: No), the diagnostic device (2) proceeds to the process of step S504.

[0432] The diagnosis device (2) determines whether the thickness stiffness diagnosis completion signal (310) is set (step S504). At this time, if the thickness stiffness diagnosis completion signal (310) is set (step S504: Yes), the process proceeds to step S505, and if the thickness stiffness diagnosis completion signal (310) is not set (step S504: No), the process ends. Here, the thickness stiffness diagnosis completion signal (310) is set when the thickness stiffness diagnosis process is executed by the thickness stiffness diagnosis unit (70).

[0433] The diagnostic device (2) determines whether an initial value exists (step S505). Here, the diagnostic device (2) determines whether an initial date and time (502x) is set. At this time, if an initial value does not exist (step S505: Yes), the diagnostic device (2) sets the initialization execution signal 2 (508) (step S508) and proceeds to processing from step S510 onwards. On the other hand, if an initial value exists (step S505: No), the diagnostic device (2) proceeds to processing of step S506.

[0434] The diagnostic device (2) determines whether the initialization flag (301t) is set (step S506). At this time, if the initialization flag (301t) is set (step S506: Yes), the diagnostic device (2) sets the initialization execution signal 2 (508) (step S508) and proceeds to processing of step S510 and thereafter. On the other hand, if the initialization flag (301t) is not set (step S506: No), the diagnostic device (2) proceeds to processing of step S507.

[0435] The diagnostic device (2) determines whether the initialization execution command (502u) is set (step S507). At this time, if the initialization execution command (502u) is set (step S507: Yes), the diagnostic device (2) sets the initialization execution signal 2 (508) (step S508) and proceeds to processing from step S510 onwards. On the other hand, if the initialization execution command (502u) is not set (step S507: No), the diagnostic device (2) sets the update execution signal (509) (step S509) and proceeds to processing from step S510 onwards.

[0436] (5-5-3. Flow Initialization Process) The diagnostic device (2) initializes the flow rate diagnosis set value (502), sets an initialization execution command (502u), sets the flow rate correction coefficient fk (28u) to an initial value of 1.0, initializes the flow rate diagnosis result (501), resets the flow rate diagnosis abnormality (501r), sets the initialization flag (501t), sets the update flag (501s), resets the flow rate calibration completion signal (120), and ends the process.

[0437] (5-5-4. Flow of stiffness and thickness initialization process) The diagnostic device (2) initializes the flow rate diagnosis set value (502), resets the initialization execution command (502u), sets the flow rate correction coefficient fk (28u) to an initial value of 1.0, initializes the flow rate diagnosis result (501), resets the flow rate diagnosis abnormality (501r), sets the initialization flag (501t), sets the update flag (501s), resets the thickness / rigidity diagnosis completion signal (310), and ends the process.

[0438] (5-5-5. Flow rate correction coefficient update process flow) The diagnostic device (2) calculates the flow rate correction coefficient, the flow rate error rate, and the flow rate fluctuation rate. At this time, if the absolute value of the flow rate fluctuation rate rqd (501c) is greater than the flow rate fluctuation allowable value (502h), the diagnostic device (2) sets the flow rate coefficient selection signal (504) and sets the flow rate correction coefficient fk (28u). Furthermore, if the absolute value of the flow rate error rate rqe (501b) is greater than the flow rate error alarm value (502r), the diagnostic device (2) sets a flow rate diagnosis abnormality (501r). On the other hand, if the absolute value of the flow rate error rate rqe (501b) is equal to or less than the flow rate error alarm value (502r), the diagnostic device (2) resets the flow rate diagnosis abnormality (501r).

[0439] The diagnostic device (2) resets the initialization flag (501t), sets the update flag (501s), resets the thickness / rigidity diagnosis completion signal (310), and ends the process.

[0440] (5-6. Flow of timing prediction diagnosis process) The flow of the timing prediction diagnosis process will be described with reference to Fig. 43. Fig. 43 is a flowchart showing an example of the flow of the entire timing prediction diagnosis process according to the embodiment. Note that the processes of steps S601 to S605 below can also be executed in a different order. Also, some of the processes of steps S601 to S605 below may be omitted.

[0441] The diagnostic device (2) determines whether an update flag is set (step S601). At this time, if an update flag is set (step S601: Yes), the diagnostic device (2) proceeds to the process of step S602. On the other hand, if none of the update flags are set (step S601: No), the diagnostic device (2) ends the process. The update flag of the diagnostic data is included in the result of each diagnosis.

[0442] The diagnostic device (2) checks the density calibration result (151), the density diagnostic result (201), the wall thickness / rigidity diagnostic result (301), and the flow rate diagnostic result (501), imports the diagnostic result data (step S602), calculates a change trend value (601) from the imported data (step S603), calculates a timing prediction diagnostic result (603) from the change trend value (601) and the diagnostic target value (602) (step S604), resets the update flag (step S605), and ends the process.

[0443] 6. Effects of the embodiment Finally, effects of the embodiment will be described below: Effects 1 to 7 corresponding to the processing according to the embodiment will be described below.

[0444] (6-1. Effect 1) In the process according to the embodiment described above, a density diagnosis result (201) relating to the density error of the fluid before and after the density calibration is generated based on a density calibration result (151) relating to the calibration of the density of the fluid generated by calibrating the Coriolis mass flowmeter (1) that measures the flow rate and density of the fluid flowing through the vibrating tube (11) based on the Coriolis force acting on the vibrated vibrating tube (11), and a calculation is performed on at least one of the thickness and rigidity of the vibrating tube (11) based on the density diagnosis result (201) to generate a thickness rigidity diagnosis result (301) relating to the change in the vibrating tube (11). Therefore, in this process, the state of the vibrating tube (11) of the Coriolis mass flowmeter (1) can be accurately diagnosed.

[0445] (6-2. Effect 2) In the process according to the embodiment described above, a density error is calculated using an initial density measurement coefficient, a density measurement coefficient indicated by the density calibration result (151), and the density of the object to be measured, and a thickness and stiffness diagnosis result (301) including at least one of results related to a thickness change and stiffness change of the vibration tube (11) is generated using a change rate of the density measurement coefficient indicated by the density diagnosis result (201) and a design value of the vibration tube (11), and an abnormality related to the vibration tube (11) is detected when the thickness and stiffness diagnosis result (301) is equal to or greater than a threshold value. Therefore, in this process, the density diagnosis result (201) and the thickness and stiffness diagnosis result (301) are effectively generated, thereby making it possible to accurately diagnose the state of the vibration tube (11) of the Coriolis mass flowmeter (1).

[0446] (6-3. Effect 3) In the process according to the embodiment described above, a thickness / rigidity diagnosis result (301) is generated that includes at least one of the inner diameter, thickness, thickness change, thickness change rate, rigidity change rate, corrosion diagnosis, and adhesion diagnosis of the vibration pipe (11). Therefore, in this process, the thickness / rigidity diagnosis result (301) is effectively used to accurately diagnose the condition of the vibration pipe (11) of the Coriolis mass flowmeter (1).

[0447] (6-4. Effect 4) In the process according to the embodiment described above, a calculation related to the flow rate of the fluid is performed based on the wall thickness / rigidity diagnosis result (301) to generate a flow rate diagnosis result (501) related to the flow rate error of the fluid. Therefore, in this process, by generating the flow rate diagnosis result (501), it is possible to accurately diagnose the state of the vibrating tube (11) of the Coriolis mass flowmeter (1) and perform a simple correction related to the flow rate.

[0448] (6-5. Effect 5) In the process according to the embodiment described above, a flow correction coefficient is calculated using at least one of the stiffness change rate, the wall thickness change rate, and the change rate of the density measurement coefficient, and based on the calculated flow correction coefficient, update control of the flow correction coefficient used by the Coriolis mass flowmeter (1) to measure the flow rate is performed. In this process, by effectively generating a flow diagnosis result (501), it is possible to accurately diagnose the state of the vibrating tube (11) of the Coriolis mass flowmeter (1) and perform simple correction related to the flow rate.

[0449] (6-6. Effect 6) In the process according to the present embodiment described above, the occurrence of a fault in the Coriolis mass flowmeter (1), the time required for maintenance or equipment replacement, the operating time, or the integrated flow rate of the fluid are predicted based on the density calibration result (151), the density diagnosis result (201), the wall thickness / rigidity diagnosis result (301), or the flow rate diagnosis result (501), and the results are generated as timing prediction diagnosis results. Therefore, in this process, the condition of the vibrating tube (11) of the Coriolis mass flowmeter (1) can be accurately diagnosed, and the diagnosis result can be effectively utilized.

[0450] (6-7. Effect 7) In the process according to the present embodiment described above, when the density calibration result (151), the density diagnosis result (201), the wall thickness stiffness diagnosis result (301), or the flow rate diagnosis result (501) exceeds a predetermined alarm value, an abnormality related to the vibrating tube (11) is notified. Therefore, in this process, the condition of the vibrating tube (11) of the Coriolis mass flowmeter (1) is accurately diagnosed, and the diagnosis result is effectively utilized to provide useful information.

[0451] 〔system〕 The information including the processing procedures, control procedures, specific names, various data and parameters shown in the above documents and drawings can be changed arbitrarily unless otherwise specified.

[0452] In addition, each component of each device shown in the figure is a functional concept, and does not necessarily have to be physically configured as shown in the figure. In other words, the specific form of distribution and integration of each device is not limited to that shown in the figure. In other words, all or part of them can be functionally or physically distributed and integrated in any unit according to various loads, usage conditions, etc.

[0453] Furthermore, each processing function performed by each device may be realized, in whole or in part, by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware using wired logic.

[0454] [Hardware] Next, an example of the hardware configuration of the diagnostic device (2) will be described. Note that other devices may have a similar hardware configuration. FIG. 44 is a diagram for explaining an example of the hardware configuration. As shown in FIG. 44, the diagnostic device (2) has a communication device (2a), a HDD (Hard Disk Drive) (2b), a memory (2c), and a processor (2d). In addition, each unit shown in FIG. 44 is connected to each other by a bus or the like.

[0455] The communication device (2a) is a network interface card or the like, and communicates with other servers. The HDD (2b) stores the programs and DB that operate the functions shown in FIG.

[0456] The processor (2d) reads out a program that executes the same processes as the respective processing units shown in Fig. 4 from the HDD (2b) or the like, and loads it into the memory (2c), thereby operating a process that executes each function described in Fig. 4 or the like. For example, this process executes the same functions as the respective processing units of the diagnosis device (2). Specifically, the processor (2d) reads out a program having the same functions as the density error diagnosis unit (61), the thickness stiffness diagnosis unit (70), the flow rate error diagnosis simple correction unit (80), the timing prediction diagnosis unit (90), and the like from the HDD (2b) or the like. Then, the processor (2d) executes a process that executes the same processes as the density error diagnosis unit (61), the thickness stiffness diagnosis unit (70), the flow rate error diagnosis simple correction unit (80), the timing prediction diagnosis unit (90), and the like.

[0457] In this way, the diagnostic device (2) operates as an information processing device that executes various processing methods by reading and executing the programs. The diagnostic device (2) can also realize functions similar to those of the above-mentioned embodiment by reading the above programs from a recording medium using a media reading device and executing the read programs. Note that the programs in these other embodiments are not limited to being executed by the diagnostic device (2). For example, the present invention can be similarly applied to cases where other computers or servers execute the programs, or where these execute the programs in cooperation with each other.

[0458] This program can be distributed via a network such as the Internet. This program can also be recorded on a computer-readable recording medium such as a hard disk, a flexible disk (FD), a CD-ROM, a magneto-optical disk (MO), or a digital versatile disk (DVD), and can be executed by being read out from the recording medium by a computer. [Explanation of symbols]

[0459] 1 Coriolis mass flowmeter 2. Diagnostic equipment 3 Calibration device 10. Detection section 11 Vibration tube 20 Conversion unit 21 Drive control unit 22 Mass flow rate calculation section 23 Density calculation section 30 Display operation section 31 External device 40 Calibration control section 41 Mass flow rate calibration section 51 Density calibration section 60 Diagnostic control unit 61 Density error diagnostic unit 70 Thickness and rigidity diagnostic section 80 Flow rate error simple correction section 90 Timing Prediction and Diagnosis Department 200 Transmitter / receiver 300 Notification Department 1000 Diagnostic Systems

Claims

1. a transceiver for acquiring a density calibration result related to the calibration of the density of a fluid generated by calibrating a Coriolis mass flowmeter that measures a flow rate and density of a fluid flowing through a vibrating tube based on a Coriolis force acting on the vibrating tube; a density error diagnosis unit that generates a density diagnosis result regarding a density error of the fluid before and after the density calibration based on the density calibration result; a thickness and stiffness diagnosis unit that performs calculations on at least one of the thickness and stiffness of the vibration tube based on the density calibration result or the density diagnosis result, and generates a thickness and stiffness diagnosis result on a change in the vibration tube; a flow rate error diagnosis simple correction unit that performs a calculation regarding a flow rate of the fluid based on the wall thickness stiffness diagnosis result and generates a flow rate diagnosis result regarding a flow rate error of the fluid; A diagnostic device comprising:

2. The density error diagnosis unit includes: Calculating the density error using an initial density measurement coefficient, a density measurement coefficient indicated by the density calibration result, and the density of the object to be measured; The thickness and rigidity diagnosis unit includes: Using the rate of change of the density measurement coefficient indicated by the density calibration result or the density diagnosis result and the design value of the vibration tube, a thickness and stiffness diagnosis result is generated, the thickness and stiffness diagnosis result including at least one result related to a thickness change, a stiffness change, corrosion, and adhesion of the vibration tube; When the wall thickness rigidity diagnosis result is equal to or greater than a threshold value, an abnormality related to the vibration pipe is detected. The diagnostic device of claim 1 .

3. The thickness and rigidity diagnosis unit includes: generating a thickness / rigidity diagnosis result including at least one of an inner diameter, a wall thickness, a wall thickness change, a wall thickness change rate, a rigidity change rate, a corrosion diagnosis, and an adhesion diagnosis of the vibration tube; The diagnostic device of claim 2.

4. The flow rate error diagnosis simple correction unit includes: generating the flow diagnostic result including at least one of a flow correction coefficient and a flow error using at least one of a stiffness change rate, a wall thickness change rate, and a density measurement coefficient change rate of the vibration pipe; and performing update control of a flow rate correction coefficient used by the Coriolis mass flowmeter to measure the flow rate based on the flow rate correction coefficient. The diagnostic device of claim 1 .

5. a timing prediction and diagnosis unit that predicts the occurrence of a fault in the Coriolis mass flowmeter, the time required for maintenance or equipment replacement, the operating time, or the integrated flow rate of the fluid based on the density calibration result, the density diagnosis result, the wall thickness and stiffness diagnosis result, or the flow rate diagnosis result, and generates the result as a timing prediction and diagnosis result; The diagnostic device of claim 1 further comprising:

6. a notification unit that notifies an abnormality related to the vibration pipe when the density calibration result, the density diagnosis result, the wall thickness rigidity diagnosis result, or the flow rate diagnosis result exceeds a predetermined alarm value; The diagnostic device of claim 5 further comprising:

7. The computer A density calibration result is obtained regarding calibration of the density of the fluid generated by calibrating a Coriolis mass flowmeter that measures a flow rate and density of the fluid flowing through a vibrating tube based on a Coriolis force acting on the vibrating tube; generating a density diagnostic result regarding a density error of the fluid before and after the density calibration based on the density calibration result; Calculating at least one of the thickness and stiffness of the vibration tube based on the density calibration result or the density diagnosis result to generate a thickness stiffness diagnosis result regarding the change of the vibration tube; Executing a calculation related to a flow rate of the fluid based on the wall thickness stiffness diagnosis result, and generating a flow rate diagnosis result related to a flow rate error of the fluid. A diagnostic method to perform the action.

8. On the computer, A density calibration result is obtained regarding calibration of the density of the fluid generated by calibrating a Coriolis mass flowmeter that measures a flow rate and density of the fluid flowing through a vibrating tube based on a Coriolis force acting on the vibrating tube; generating a density diagnostic result regarding a density error of the fluid before and after the density calibration based on the density calibration result; Calculating at least one of the thickness and stiffness of the vibration tube based on the density calibration result or the density diagnosis result to generate a thickness stiffness diagnosis result regarding the change of the vibration tube; Executing a calculation related to a flow rate of the fluid based on the wall thickness stiffness diagnosis result, and generating a flow rate diagnosis result related to a flow rate error of the fluid. A diagnostic program that performs the process.

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