Gasket condition estimation method, gasket condition estimation device, and program

Abstract

To enable estimation of gasket condition.SOLUTION: A gasket condition estimation method is provided, comprising receiving vibration propagating through a gasket when vibration of a characteristic frequency indicative of characteristics of the gasket is applied to the gasket, and estimating the condition of the gasket on the basis of signal intensity of the received vibration and a relationship between the gasket condition and the signal intensity of vibration at the characteristic frequency.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] Gasket fastening is a necessary construction work when constructing new infrastructure. It is necessary to manage the fastening of gaskets, but the fastening work is affected by the skills of the worker, the size and distortion of the pipes, and the work environment. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-258879 A [Patent Document 2] JP 2003-270219 A [Patent Document 3] JP 2005-52212 A [Patent Document 4] JP 2011-5058 A Summary of the Invention [Problem to be solved by the invention]

[0004] It is difficult to determine the condition of a gasket, such as the load being applied to it, from an external inspection. An object of the present invention is to provide a gasket condition estimating method, a gasket condition estimating device, and a program that solve the above-mentioned problems. [Means for solving the problem]

[0005] One aspect of the present invention is a gasket state estimation method that receives vibrations that propagate through a gasket when vibrations at a characteristic frequency that indicates characteristics of the gasket are input to the gasket, and estimates the state of the gasket based on a relationship between a signal strength of the received vibrations, the state of the gasket, and the signal strength of the vibrations at the characteristic frequency. Effect of the Invention

[0006] According to the present invention, the condition of the gasket can be estimated. [Brief description of the drawings]

[0007] [Figure 1] 2 is an example of a configuration of a gasket-state relation data generating system according to the present embodiment. [Diagram 2] 4A to 4C are diagrams illustrating an example of a received signal acquired by a received signal acquisition unit and a converted received spectrum. [Diagram 3] FIG. 13 is a diagram showing the relationship between the load applied to the gasket and the received vibration spectrum. [Figure 4] 1 is a graph showing the relationship between the applied load (surface pressure) and the signal intensity at a characteristic frequency of a gasket. [Diagram 5] 1 is a diagram showing an example of the configuration of a gasket state estimating device 15 according to a first embodiment. [Figure 6] 4 is a flowchart showing the operation of the gasket condition relation data generating device. [Figure 7] 4 is a flowchart showing the operation of the gasket state estimating device 15 according to the first embodiment. [Figure 8] 6 is a diagram showing an example of the configuration of a gasket state estimating device 15 according to a second embodiment. FIG [Figure 9] 6 is a flowchart showing the operation of a gasket state estimating device 15 according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an example of the configuration of a gasket-state relational data generating system 1 according to this embodiment. The gasket condition related data generating system 1 includes an oscillation sensor 12, a vibration receiving sensor 13, and a gasket condition related data generating device .

[0009] The oscillation sensor 12 inputs vibration to the gasket 20. The oscillation sensor 12 is, for example, an acoustic emission (AE) sensor or a piezoelectric sensor such as a piezo actuator. The frequency of the vibration input by the oscillation sensor 12 to the gasket 20 is controlled by an oscillation sensor control unit 142, which will be described later.

[0010] The gasket 20 is used to obtain a relationship between the condition of the gasket 20 and the signal strength of the vibration of the gasket 20 .

[0011] The vibration receiving sensor 13 measures vibrations propagating through the gasket 20. The vibration receiving sensor 13 is, for example, an AE sensor or an acceleration sensor. The vibration receiving sensor 13 may be attached to the front and back sides of the gasket 20 to measure vibrations propagating through both sides.

[0012] The gasket state relation data generating device 14 includes an oscillation sensor control unit 142 , a received signal acquiring unit 143 , a characteristic frequency identifying unit 144 , and a gasket state estimating unit 145 .

[0013] The oscillation sensor control unit 142 controls the frequency of the vibration that the oscillation sensor 12 inputs to the gasket 20. The oscillation sensor control unit 142 controls the oscillation sensor 12 to input white vibration including vibrations of multiple frequencies to the gasket 20.

[0014] The receiving signal acquisition unit 143 acquires the receiving signal measured by the receiving sensor 13. The receiving signal acquisition unit 143 converts the receiving signal into a receiving spectrum indicating the signal strength for each spectrum. FIG. 2 is a diagram showing an example of the receiving signal acquired by the receiving signal acquisition unit 143 and the converted receiving spectrum. The signal strength at a specific frequency in the receiving spectrum changes depending on the state of the gasket 20. The receiving spectrum can also change depending on the shape of the gasket.

[0015] The characteristic frequency identification unit 144 identifies a characteristic frequency of the gasket 20 based on the relationship between the state of the gasket 20 and the received vibration spectrum. The characteristic frequency is a frequency that represents the characteristics of the gasket 20.

[0016] The output unit 145 outputs data on the characteristic frequency of the gasket 20 and data indicating the relationship between the signal strength at a particular frequency and the state of the gasket 20 .

[0017] The state of the gasket 20 is, for example, the load applied to the gasket 20. FIG. 3 is a diagram showing the relationship between the load applied to the gasket 20 and the reception spectrum. In the graph of FIG. 3, the vertical axis represents frequency, the horizontal axis represents applied load, and a color chart represents signal intensity. The characteristic frequency identification unit 144 identifies a characteristic frequency of the gasket 20 based on, for example, the relationship between the load applied to the gasket 20 and the reception spectrum. For example, the characteristic frequency is a frequency at which the signal intensity changes most significantly when the load applied to the gasket 20 is changed.

[0018] 4 is a graph showing the relationship between the applied load (surface pressure) and the signal intensity at the characteristic frequency of the gasket 20. At the characteristic frequency, the signal intensity changes significantly when the surface pressure is changed.

[0019] 5 is a diagram showing an example of the configuration of gasket state estimating device 15 according to the first embodiment. Gasket state estimating device 15 according to the first embodiment includes an oscillation sensor control unit 152, a received signal acquiring unit 153, a gasket state estimating unit 154, a storage unit 155, and an output unit 156. The storage unit 155 stores data indicating the relationship between the characteristic frequency value of the gasket 20 and the signal strength at a specific frequency, and the state of the gasket 20. The data indicating the relationship between the characteristic frequency value of the gasket 20 and the signal strength at a specific frequency, and the state of the gasket 20 is data output from the gasket-state relationship data generating device 14, for example.

[0020] A gasket 20 shown in Fig. 5 is sandwiched between pipe joints and acts as a fastener. A load is applied to the gasket 20 from the pipe it is sandwiched between. If the gasket 20 has a part protruding from the pipe in order to input and measure vibration, it becomes easier to input and measure vibration.

[0021] 1, the oscillation sensor 12 shown in Fig. 5 inputs vibrations to the gasket 20. The vibration receiving sensor 13 in Fig. 5 measures vibrations propagating through the gasket 20, similar to the vibration receiving sensor 13 in Fig. 1.

[0022] The oscillation sensor control unit 152 controls the oscillation sensor 12 to input vibrations of a specific frequency stored in the storage unit 155. The received vibration signal acquisition unit 153 acquires the received vibration signal measured by the vibration sensor 13 in the same manner as the received vibration signal acquisition unit 143.

[0023] The gasket state estimation unit 154 estimates the state of the gasket 20 based on the signal strength of the received signal at the acquired specific frequency and data stored in the memory unit 155 indicating the relationship between the signal strength at the specific frequency and the state of the gasket 20.

[0024] The output unit 156 outputs the estimated state of the gasket 20 .

[0025] This enables the gasket condition estimation unit 154 to estimate the condition of the gasket 20.

[0026] 6 is a flowchart showing the operation of the gasket state relation data generating device 14. First, the state of the gasket 20 is changed (step S101). The oscillation sensor control unit 142 controls the oscillation sensor 12 to apply white vibration to the test object 20 (step S102). The received signal acquisition unit 143 acquires the received signal measured by the received sensor 13 (step S103). If the state has not been changed and measured a predetermined number of times (step S104: NO), the state of the gasket is changed (step S105) and the operation from step S102 is performed. In addition, the received signal acquisition unit 143 converts the received signal into a received spectrum to calculate the relationship between the state of the gasket 20 and the received spectrum.

[0027] The characteristic frequency identification unit 144 identifies the characteristic frequency of the gasket 20 based on the relationship between the state of the gasket 20 and the reception spectrum (step S106). The output unit 145 outputs data indicating the characteristic frequency and the relationship between the signal intensity at the characteristic frequency and the state of the gasket (step S107).

[0028] 7 is a flowchart showing the operation of the gasket state estimation device 15 according to the first embodiment. First, the oscillation sensor control unit 152 controls the oscillation sensor 12 to apply vibration of a specific frequency to the gasket 20 (step S201). The received vibration signal acquisition unit 153 acquires a received vibration signal measured by the vibration sensor 13 (step S202). The gasket state estimation unit 153 identifies the signal strength at the specific frequency (step S203) and estimates the state of the gasket (step S204).

[0029] 8 is a diagram showing an example of the configuration of a gasket state estimating device 15 according to the second embodiment. The gasket state estimating device 15 according to the second embodiment includes a determination unit 157 in addition to the components of the gasket state estimating device 15 according to the first embodiment.

[0030] The determination unit 157 determines the soundness of the gasket 20 as a fastened body based on the state of the gasket 20 estimated by the gasket state estimation unit 154. The determination unit 157 determines whether or not it is necessary to increase the load applied to the gasket 20 based on, for example, the load applied to the gasket 20 estimated by the gasket state estimation unit 154. The determination unit 157 determines that it is necessary to increase the load applied to the gasket 20 when, for example, the load applied to the gasket 20 estimated by the gasket state estimation unit 154 is smaller than a predetermined value.

[0031] The determination unit 157 determines whether or not the gasket 20 needs to be replaced based on the state of the gasket 20 estimated by the gasket state estimation unit 154, for example.

[0032] In the second embodiment, the output unit 156 outputs the result of the determination made by the determination unit 157. A person in charge of the piping including the gasket 20 tightens or replaces the gasket 20 based on the result of the determination, thereby increasing the load applied to the gasket 20.

[0033] 9 is a flowchart showing the operation of the gasket state estimating device 15 according to the second embodiment. The operations from steps S301 to S304 are the same as the operations from steps S201 to S204 in FIG. The determination unit 157 determines the soundness of the gasket 20 as a fastened body based on the estimated state of the gasket 20 (step S305). The output unit 156 outputs the determination result (step S306).

[0034] The gasket state estimating device 15 according to the second embodiment can judge the soundness of the gasket as a fastened body. Based on the judgment result, the gasket can be tightened or replaced, etc., and the load applied to the gasket can be increased, thereby maintaining the soundness of the gasket functioning as a fastened body.

[0035] The state of the gasket 20 is not limited to the load applied to the gasket 20. The state of the gasket 20 includes, for example, the compressed state or deformation state of the gasket 20, thermal deterioration, and permeation of an internal fluid.

[0036] The storage unit 155 may store characteristic frequency values ​​that differ depending on the type of gasket 20 and data indicating the relationship between the signal intensity and the state of the gasket 20. The storage unit 155 may store characteristic frequency values ​​that differ depending on the type of state of the gasket 20 estimated by the gasket state estimation device 15. The gasket state estimation device 15 has a function of switching the type of gasket 20 and the type of state of the gasket 20 to be estimated, and depending on the switched type of gasket 20 and the state to be estimated, the oscillation sensor control unit 152 may switch the frequency of the vibration input to the gasket 20, and the gasket state estimation unit 154 may change the state to be estimated.

[0037] The gasket condition estimation device 15 may be used when a pipe sandwiching the gasket 20 is fastened for the first time, or may be used to monitor the condition of the gasket 20 in a fastened pipe.

[0038] The oscillation sensor 12 and the vibration receiving sensor 13 do not necessarily input vibration to the gasket 20 and measure the vibration of the gasket 20. For example, the oscillation sensor 12 may input vibration to a flange that contacts the gasket 20, and the vibration receiving sensor 13 may measure the vibration transmitted to the gasket 20 via the flange. Also, for example, the oscillation sensor 12 may input vibration to the gasket 20, and the vibration receiving sensor 13 may be in contact with the flange and measure the vibration transmitted to the flange via the gasket 20.

[0039] Other Embodiments Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design changes, etc. are possible within the scope that does not deviate from the gist of the present invention.

[0040] At least some of the functions of the gasket state relation data generating device 14 and the gasket state estimating device 15 may be realized by a computer. In that case, a program for realizing the functions of the gasket state relation data generating device 14 and the gasket state estimating device 15 may be recorded in a computer-readable recording medium, and the program recorded in the recording medium may be read into a computer system and executed to realize the functions. The computer system includes hardware such as a processor, an OS, and peripheral devices. The programs of the gasket state relation data generating device 14 and the gasket state estimating device 15 may be recorded in a computer-readable recording medium. The computer-readable recording medium is, for example, a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, or a storage device such as a hard disk built into a computer system. The programs of the gasket state relation data generating device 14 and the gasket state estimating device 15 may be transmitted via an electric communication line. [Explanation of symbols]

[0041] 1 Gasket state relational data generation system, 12 Oscillation sensor, 13 Vibration receiving sensor, 14 Gasket state relational data generation device, 142, 152 Oscillation sensor control unit, 143, 153 Vibration receiving signal acquisition unit, 144 Feature frequency identification unit, 145 Output unit, 15 Gasket state estimation device, 154 Gasket state estimation unit, 155 Memory unit, 20 Gasket

Claims

1. receiving vibrations propagating through the gasket when vibrations having a characteristic frequency indicative of a characteristic of the gasket are input to the gasket; estimating a state of the gasket based on a signal strength of the received vibration and a relationship between a state of the gasket and a signal strength of the vibration at the characteristic frequency; Gasket condition estimation method.

2. The state of the gasket is a surface pressure applied to the gasket. The method for estimating a gasket condition according to claim 1 .

3. The gasket condition estimating method according to claim 1 , wherein the condition of the gasket is thermal deterioration, chemical deterioration, or fluid permeation of the gasket itself.

4. The characteristic frequency of the gasket and the relationship between the state of the gasket and the signal intensity of the vibration at the characteristic frequency are determined based on a received spectrum of the vibration propagating through the gasket by inputting a white vibration to the gasket. The method for estimating a gasket state according to claim 1 .

5. determining the soundness of the gasket as a fastening body based on the estimated state of the gasket; The method for estimating a gasket condition according to claim 1 .

6. determining whether or not it is necessary to increase the load applied to the gasket based on the estimated state of the gasket; The method for estimating a gasket condition according to claim 5 .

7. determining whether or not the gasket needs to be replaced based on the estimated condition of the gasket; The method for estimating a gasket condition according to claim 5 .

8. The characteristic frequency of the gasket and the relationship between the state of the gasket and the signal intensity of the vibration at the characteristic frequency are determined based on a received spectrum of the vibration propagating through the gasket by inputting a white vibration to the gasket. The method for estimating a gasket condition according to claim 5 .

9. a received signal acquisition unit that receives vibrations that propagate through the gasket when vibrations having a characteristic frequency that indicates a characteristic of the gasket are input to the gasket; a gasket state estimation unit that estimates a state of the gasket based on a signal strength of the received vibration, and a relationship between a state of the gasket and a signal strength of the vibration at the characteristic frequency; A gasket state estimation device comprising:

10. A program for causing a computer to execute the gasket state estimating method according to claim 1.

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