Wear condition prediction device, prediction method, and prediction program

Abstract

The present invention addresses the problem of providing a prediction device, a prediction method, and a prediction program that make it possible to predict the wear condition of a seal member in a shaft seal device without disassembling the shaft seal device.　In order to solve the problem described above, a prediction device, and a prediction method and a prediction program related to the prediction device are provided. The prediction device comprises a wear condition prediction means to which a shaft seal device is attached. The shaft seal device includes: a seal member including a fixed side member having a sliding surface and a rotary side member having a sliding surface; and a pressing part that applies pressing force so that the sliding surface of the fixed side member and the sliding surface of the rotary side member are in close contact. The wear condition prediction means predicts the wear condition of the seal member on the basis of a change in the pressure inside a fluid chamber in which a fluid moves.　According to the present invention, it is possible to predict the wear condition of the seal member on the basis of a change in the pressure inside the fluid chamber due to the wear of the seal member. This makes it possible to accurately predict the wear condition of the seal member without disassembling the shaft seal device.

Description

Technical Field

[0001] The present invention relates to a prediction device, a prediction method, and a prediction program for predicting the wear state of a seal member in a shaft seal device.

Background Art

[0002] Generally, in the rotating shaft portion of fluid equipment used for transferring fluids, etc., a shaft seal device is attached to prevent the fluid inside the equipment from leaking to the outside and to prevent gases (air), liquids, etc. from the outside of the equipment from flowing into the equipment.

[0003] As one of such shaft seal devices, one called a mechanical seal is known. A general mechanical seal includes a seal member composed of a rotating ring and a stationary ring, and uses the elastic force of a spring such as a coil spring to bring the rotating ring and the stationary ring into a closely attached state, and by rotationally driving the rotating ring to cause relative rotation, the sealing performance of the seal member is enhanced to suppress fluid leakage.

[0004] Here, since the rotating ring in the mechanical seal rotates together with the rotating shaft and rubs against the stationary ring, the surfaces (sliding surfaces) where the rotating ring and the stationary ring are in close contact gradually wear. When the wear of the rotating ring or the stationary ring progresses, the close contact state between the rotating ring and the stationary ring cannot be maintained, resulting in a decrease in sealing performance, or cracks may occur in the rotating ring or the stationary ring, leading to a situation where fluid leakage occurs. Therefore, it is preferable to accurately grasp the state of the mechanical seal.

[0005] For example, Patent Document 1 describes a device that analyzes the high-frequency vibration generated by a mechanical seal using a high-frequency vibration sensor and evaluates the sliding state of the mechanical seal.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] However, although the device described in Patent Document 1 has been improved to avoid being affected by noise from bearings and fluid noise other than mechanical seals, there is a risk that it may not be able to completely eliminate noise. For this reason, in order to understand the condition of the mechanical seal using the device described in Patent Document 1, it is necessary to use it in a place where there is no noise from other devices, and there are many problems in terms of conditions related to use and operation that make it difficult to put into practical use.

[0008] Currently, there is no established method for accurately assessing the condition of mechanical seals from the outside, and in reality, mechanical seals are either replaced periodically or only after fluid leakage occurs. In particular, mechanical seals require disassembly for inspection and replacement, and installation requires high precision, resulting in a significant burden on maintenance workers. Therefore, there is a need to accurately assess the wear condition of sealing components in shaft sealing devices such as mechanical seals from the outside, and to appropriately determine the timing of seal component replacement, thereby reducing the burden on maintenance workers and lowering costs.

[0009] Therefore, the object of the present invention is to provide a prediction device, prediction method, and prediction program that can predict the wear state of the sealing member in a shaft seal device without disassembling the shaft seal device. [Means for solving the problem]

[0010] As a result of diligent research into the above-mentioned problems, the inventors focused on the pressure change inside the fluid chamber to which the shaft seal device is installed as a phenomenon that occurs when wear occurs in the sealing member of the shaft seal device. They discovered that it is possible to predict the wear state of the sealing member based on this pressure change, and thus completed the present invention. In other words, the present invention relates to the following prediction device, prediction method, and prediction program.

[0011] The present invention provides a predictive device for solving the above problems, which predicts the wear state of a seal member in a shaft seal device, wherein the shaft seal device comprises a seal member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, and a pressing part that presses the sliding surface of the fixed side member and the sliding surface of the rotating side member into close contact, and is provided with a wear state prediction means that predicts the wear state of the seal member based on pressure changes inside a fluid chamber in which a fluid moves. According to the prediction device of the present invention, instead of the shaft seal device itself, a wear state prediction means is provided that predicts the wear state of the seal member in the shaft seal device based on the change in pressure inside the fluid chamber in which the shaft seal device is installed due to wear of the seal member in the shaft seal device. This makes it possible to accurately predict the wear state of the seal member without disassembling the shaft seal device, and to appropriately determine when the seal member should be replaced. Furthermore, this makes it possible to reduce the burden on workers and reduce costs associated with maintenance work on the shaft seal device.

[0012] Furthermore, one embodiment of the prediction device of the present invention is characterized by further comprising a wear condition display unit that displays the wear condition of the sealing member. This feature allows operators to accurately understand the condition and wear tendency of the sealing members in the shaft sealing device, making it easier to make appropriate decisions regarding subsequent actions.

[0013] Furthermore, in one embodiment of the prediction device of the present invention, the wear state prediction means is characterized by comprising a fluid temperature measuring means for measuring the temperature of the fluid. This feature allows for the measurement of the temperature of the fluid itself as it moves through the fluid chamber, thereby enabling the understanding of temperature changes in the fluid, easy detection of associated pressure changes within the fluid chamber, and use for predicting the wear state of the seal components. Furthermore, in conjunction with predicting the wear state of the seal components, it becomes possible to perform quality control of the fluid.

[0014] Furthermore, in one embodiment of the prediction device of the present invention, the wear state prediction means is characterized by comprising a fluid flow rate measuring means for measuring the flow rate of a fluid. This feature allows for the measurement of the fluid flow rate within the fluid chamber, enabling the understanding of fluid flow rate changes, easy detection of associated pressure changes within the fluid chamber, and subsequent prediction of seal wear. Furthermore, this, combined with the prediction of seal wear, allows for fluid quality control.

[0015] Furthermore, one embodiment of the prediction device of the present invention is characterized by further providing a pressure degree detection means for detecting the degree of pressure applied to the pressing portion. This feature allows for the detection of the degree of pressure by further providing a means for detecting the degree of pressure. This makes it possible to grasp the force with which the fixed-side member and the rotating-side member are pressed by the pressing part, allowing for a more accurate prediction of the wear state of the sealing member without disassembling the shaft seal device, and enabling a more appropriate determination of when the sealing member needs to be replaced. Furthermore, this will further reduce the burden on workers and lower costs associated with maintenance work on the shaft seal device.

[0016] The present invention provides a prediction method for solving the above problems, which is a method for predicting the wear state of a seal member in a shaft seal device, characterized in that the shaft seal device comprises a seal member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, and a pressing part that presses so that the sliding surface of the fixed side member and the sliding surface of the rotating side member come into close contact, and the method provides a wear state prediction step in which the wear state of the seal member is predicted based on the pressure change inside a fluid chamber in which a fluid moves. According to the prediction method of the present invention, the wear state of the seal member is predicted not by the shaft seal device itself, but by the change in pressure inside the fluid chamber in which the shaft seal device is installed due to wear of the seal member in the shaft seal device. This wear state prediction step allows for accurate prediction of the wear state of the seal member without disassembling the shaft seal device, making it possible to appropriately determine the timing of seal member replacement. Furthermore, this reduces the burden on workers and costs associated with maintenance work on the shaft seal device.

[0017] The present invention provides a prediction program for solving the above problems, which predicts the wear state of a seal member in a shaft seal device, wherein the shaft seal device comprises a seal member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, and a pressing part that presses the sliding surface of the fixed side member and the sliding surface of the rotating side member into close contact, and the present invention provides a wear state prediction process that predicts the wear state of the seal member based on pressure changes inside a fluid chamber in which a fluid moves. According to the prediction program of the present invention, instead of the wear of the shaft seal device itself, wear of the seal member in the shaft seal device causes a change in the pressure inside the fluid chamber to which the shaft seal device is installed. By performing a wear state prediction process that predicts the wear state of the seal member, it is possible to accurately predict the wear state of the seal member without disassembling the shaft seal device, and to appropriately determine when the seal member should be replaced. Furthermore, this makes it possible to reduce the burden on workers and lower costs associated with maintenance work on the shaft seal device. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a prediction device, prediction method, and prediction program that can predict the wear state of a sealing member in a shaft seal device without disassembling the shaft seal device. [Brief explanation of the drawing]

[0019] [Figure 1]It is a schematic explanatory view showing the structure of the shaft seal device and the prediction device in the first embodiment of the present invention. [Figure 2] It is a schematic explanatory view showing another aspect of the shaft seal device in the first embodiment of the present invention. [Figure 3] It is a schematic explanatory view showing the structure of the prediction device in the second embodiment of the present invention. [Figure 4] It is a schematic explanatory view showing another aspect of the prediction device in the second embodiment of the present invention. [Figure 5] It is a schematic explanatory view showing the structure of the prediction device in the third embodiment of the present invention. [Figure 6] It is a schematic explanatory view showing another aspect of the shaft seal device and the prediction device in the third embodiment of the present invention.

Mode for Carrying Out the Invention

[0020] Hereinafter, a prediction device, a prediction method, and a prediction program according to the present invention will be described in detail while referring to the drawings. Note that the prediction device described in the embodiment is merely an example for explaining the prediction device in the present invention, and is not limited thereto. Further, the prediction method and prediction program of the present invention shall be replaced with the following description of the structure and operation of the prediction device.

[0021] The present invention is a device, method, and program for predicting the wear state of a seal member in a shaft seal device. Here, the shaft seal device in the present invention is provided on a rotating shaft of various devices such as fluid equipment that transfers fluid, and is for preventing the leakage of fluid from the inside of the device and the inflow of fluid from the outside of the device. Note that the shaft seal device in the present invention only needs to include a seal member and a pressing portion described later and be able to prevent the leakage of fluid on the rotating shaft, and the specific structure other than the seal member and the pressing portion is not particularly limited. For example, the shaft seal device in the present invention includes various accessory structures known in mechanical seals. Furthermore, the equipment on which the shaft sealing device according to the present invention is installed is not particularly limited as long as it has a rotating shaft and is required to have sealing performance on the rotating shaft, and is equipped with a fluid chamber in which fluid moves. For example, examples of equipment on which the shaft sealing device according to the present invention is installed include compressors and slurry pumps.

[0022] [First Embodiment] Figure 1 is a schematic diagram illustrating the structure of a shaft sealing device and a prediction device in a first embodiment of the present invention. As shown in Figure 1, the prediction device 1A in this embodiment is attached to a fluid chamber 102 in the equipment 100 through which fluid moves, and is equipped with a wear state prediction means 2 that predicts the wear state of the seal member 20 based on pressure changes inside the fluid chamber 102 for a shaft seal device 10 which includes a seal member 20 and a pressing part 30. Also in Figure 1, the right side of the wall surface W of the equipment 100 is the housing 101 side of the equipment and is connected to the rotation drive unit (not shown) of the rotating shaft R. On the other hand, the left side of the wall surface W of the equipment is the fluid chamber 102 side through which fluid moves.

[0023] The device 100 in this embodiment is not particularly limited, as long as it has a fluid chamber 102 and is fitted with a shaft seal device 10. However, as shown in Figure 1, a device that maintains a negative pressure state in the fluid chamber 102 is a particularly preferred example. Specific examples of this device 100 include a slurry pump that transfers powder and liquid in a stirred and mixed state, and a dispersion device that introduces powder and liquid and performs stirring and mixing. In such a device 100, it is preferable to maintain a negative pressure state in the fluid chamber 102 in order to rapidly introduce the powder and ensure the stirring and mixing efficiency and stability of the slurry. In particular, if the device 100 is a dispersion device that performs dispersion by cavitation and shear force (such as the Jet Paster® manufactured by Nippon Spindle Manufacturing Co., Ltd.), maintaining a negative pressure state in the fluid chamber 102, which also functions as a mixing section into which powder and liquid are introduced, is important for stable processing. The means of creating a negative pressure state in the fluid chamber 102 are not particularly limited. For example, one could connect a pressure reducing mechanism such as a pressure reducing pump to the fluid chamber 102, or provide a structure in the fluid chamber 102 that generates cavitation, causing the inside of the fluid chamber 102 to be depressurized as the fluid moves due to the effect of cavitation.

[0024] As shown in Figure 1, the shaft sealing device 10 in this embodiment is installed on the rotating shaft R of the equipment and includes a sealing member 20 comprising a fixed-side member 21 having a sliding surface 21a and a rotating-side member 22 having a sliding surface 22a, and a pressing part 30 that presses the sliding surface 21a of the fixed-side member 21 and the sliding surface 22a of the rotating-side member 22 so that they come into close contact. Furthermore, in this embodiment, the shaft sealing device 10 uses the pressing portion 30 to bring the sliding surface 21a of the fixed-side member 21 and the sliding surface 22a of the rotating-side member 22 into close contact, thereby increasing the sealing performance of the sealing member 20 and preventing fluid leakage and inflow from between the sliding surfaces 21a and 22a. The following describes the various components of the shaft sealing device 10.

[0025] The sealing member 20 comprises a fixed-side member 21 and a rotating-side member 22. The fixed-side member 21 and the rotating-side member 22 are arranged coaxially and concentrically with respect to the rotation axis R, and their respective sliding surfaces 21a and 22a are positioned opposite each other. In this embodiment, the fixed-side member 21 and the rotating-side member 22 can be any member whose sliding surfaces 21a and 22a face each other, and whose relative rotational sliding surfaces 21a and 22a are driven by the rotation of the rotating-side member 22, thereby preventing fluid leakage. The specific structure is not particularly limited. For example, as shown in Figure 1, the fixed-side member 21 is arranged to be movable in the axial direction via a casing 23 fixed to the wall surface W that separates the fluid chamber 102 through which the fluid moves from the housing 101 in the device 100, while the rotating-side member 22 is fixed to the rotation axis R via a support member 24. It should be noted that the fixed-side member 21 and the rotating-side member 22 in this embodiment are not limited to those shown in Figure 1, and known structures for the fixed ring and rotating ring in a mechanical seal can be used.

[0026] The materials of the fixed-side member 21 and the rotating-side member 22 are not particularly limited, and should be materials commonly used in mechanical seals, taking into consideration mechanical strength, wear resistance, self-lubrication, and thermal conductivity. Specifically, for example, ultrahard materials such as silicon carbide (SiC) and tungsten carbide (WC), as well as other hard materials such as ceramics (chromium oxide and alumina), can be used. In addition, soft materials such as carbon and resin may be provided on the surface of hard materials or metal materials (stainless steel, etc.) to improve lubricity at the sliding surface.

[0027] The pressing portion 30 is for pressing the sliding surface 21a of the fixed-side member 21 and the sliding surface 22a of the rotating-side member 22 so that they come into close contact. The pressing portion 30 can be anything that presses against the fixed-side member 21 or the rotating-side member 22, and the means and structure for pressing are not particularly limited. For example, as shown in Figure 1, the pressing portion 30 can be a spring mechanism 31 such as a coil spring arranged inside the casing 23. In this case, as shown in Figure 1, the elastic force of the spring mechanism 31 presses the fixed-side member 21 against the rotating-side member 22. In Figure 1, the pressing portion 30 is shown as pressing from the fixed-side member 21 to the rotating-side member 22, but it is not limited to this. The pressing portion 30 may also be pressing from the rotating-side member 22 to the fixed-side member 21.

[0028] In this case, the pressing portion 30 is designed to apply a force P to the fixed-side member 21 (or the rotating-side member 22) such that the sliding surface 21a of the fixed-side member 21 and the sliding surface 22a of the rotating-side member 22 maintain close contact and are able to rotate and slide relative to each other.

[0029] Note that the structure of the shaft seal device 10 in this embodiment is not limited to that shown in Figure 1. Figure 2 is a schematic diagram illustrating another embodiment of the shaft sealing device in this embodiment. For example, as shown in Figure 2, instead of providing a casing 23, a support member 25 is provided to support the fixed-side member 21. The end of this support member 25 opposite to the side where the fixed-side member 21 is located (the right side in Figure 2) is in contact with the pressing part 30 (spring mechanism 31). As a result, the support member 25 is pressed by the pressing part 30 (spring mechanism 31), causing the fixed-side member 21 to be pressed against the rotating-side member 22. The shape, number, and arrangement of the spring mechanism 31 are not particularly limited. As shown in Figure 2, multiple spring mechanisms 31 may be provided, or a single spring mechanism 31 may be provided so as to press the entire support member 25. The shaft sealing device 10 in Figure 2 has the advantage of reducing manufacturing and assembly costs compared to the shaft sealing device 10 shown in Figure 1, due to its simpler component structure.

[0030] In this case, the sealing member 20 of the shaft seal device 10 experiences wear on the sliding surfaces 21a and 22a of the fixed-side member 21 and the rotating-side member 22 due to relative rotational sliding. When the sliding surfaces 21a and / or 22a of the sealing member 20 wear down, the close contact between the sealing member 20 and the fixed-side member 21 and the rotating-side member 22 cannot be maintained, reducing the sealing performance of the sealing member 20 and causing fluid leakage. Furthermore, wear on the sealing member 20 reduces the mechanical strength of the fixed-side member 21 and the rotating-side member 22, making them more susceptible to cracking, which can also lead to fluid leakage. Therefore, by predicting the wear state of the sealing member 20 of the shaft seal device 10 using the prediction device 1A in this embodiment, it becomes possible to perform maintenance work on the shaft seal device 10 at an appropriate timing.

[0031] In this embodiment, the prediction device 1A is provided with the shaft seal device 10 described above, and includes a wear state prediction means 2 that performs the process of predicting the wear state of the seal member based on the pressure change in the fluid chamber 102 through which fluid moves.

[0032] As wear of the sealing member 20 progresses, friction between the sliding surfaces 21a and 22a makes it easier for cracks to form in the fixed-side member 21 and / or the rotating-side member 22. When cracks form in the sealing member 20, the sealing performance of the sealing member 20 deteriorates. At this time, in the fluid chamber 102, which is under negative pressure, gas from inside the housing 101 flows into the fluid chamber 102 through the cracks, causing the pressure (degree of pressure reduction) in the fluid chamber 102 to rise rapidly. Therefore, in this embodiment, the wear state prediction means 2 detects the pressure change in the fluid chamber 102, and by using the detection result, it becomes possible to predict the wear state of the seal member 20. In this embodiment, it is preferable to perform the prediction of the wear state using the prediction device 1A while the device 100 is in operation. Furthermore, if the device 100 is a dispersion device that performs dispersion by cavitation and shear force, such as a jet paster (registered trademark), then by performing the prediction while the powder is being introduced and the slurry is circulating (during circulation operation) during slurry preparation using the device 100, it becomes possible to accurately predict the wear state of the seal member 20.

[0033] One example of the wear state prediction means 2 is, for example, as shown in Figure 1, a pressure gauge M1 is installed in the fluid chamber 102 to measure the pressure P1 inside the fluid chamber 102, and information related to the change in the measured value over time is collected and analyzed to directly detect the change in pressure P1. In other words, the wear state prediction means 2 includes a measurement unit 2a equipped with a pressure gauge M1 for measuring the pressure P1 in the fluid chamber 102, and a calculation unit 2b that collects and analyzes the value obtained by the measurement unit 2a (pressure gauge M1). Furthermore, the measurement unit 2a and the calculation unit 2b may include a computing device that executes programs necessary for data acquisition and data calculation (comparison calculation, etc.) using a processor such as a CPU. Here, the program that operates the measurement unit 2a and the calculation unit 2b corresponds to the prediction program in this embodiment.

[0034] Furthermore, the wear state prediction means 2 is not limited to a means for directly detecting changes in pressure P1, but may also detect pressure changes in the fluid chamber by other means. For example, if the pressure (degree of reduction) inside the fluid chamber 102 increases, changes will also occur in the temperature and flow rate of the fluid moving inside the fluid chamber 102. More specifically, for example, if a crack occurs in the sealing member 20, the sealing performance of the sealing member 20 deteriorates, and gas (air) flows into the fluid chamber 102, causing the fluid temperature to drop. In addition, the influx of gas (air) into the fluid chamber 102 causes bubbles to form in the slurry, resulting in pulsation, which makes the fluid delivery unstable and reduces the flow rate. Therefore, other examples of wear state prediction means 2 include, in addition to means for directly detecting changes in pressure P1, means for measuring the temperature of the fluid in the fluid chamber 102, and means for measuring the flow rate of the fluid in the fluid chamber 102. Here, instead of the pressure gauge M1, the wear state prediction means 2 may be provided with a temperature measuring device (thermometer, temperature sensor, etc.) to measure the temperature of the fluid and a flow rate measuring device (flow meter, etc.) to measure the flow rate of the fluid, and by collecting and analyzing information related to the changes in these measured values ​​over time, the change in pressure P1 may be detected indirectly. In other words, the wear state prediction means 2 may include a measuring unit equipped with measuring devices to measure the temperature and flow rate of the fluid in the fluid chamber 102, and a calculation unit that collects and analyzes the values ​​obtained by the measuring unit. The measuring unit and calculation unit in this case may also be executed by the prediction program in this embodiment. This makes it possible to predict the wear state of the sealing components and, in conjunction with this, perform quality control of the fluid.

[0035] In the wear state prediction means 2, one example of collecting and analyzing information related to the change in pressure P1 over time is to predict that the wear state of the sealing member 20 is considerably advanced when the value of pressure P1 obtained by the measurement unit exceeds a preset threshold. Another example involves comparing the pressure P1 value obtained from the measurement unit with the value obtained from the previous measurement, and predicting that the wear state of the sealing member 20 has progressed considerably if the amount of change exceeds a preset threshold. The threshold set here only needs to be at least the upper limit value among the upper and lower limits of pressure P1, and both may be set.

[0036] Furthermore, the wear condition prediction means 2 may also be equipped with a notification unit that, based on the results of collecting and analyzing information related to the change in pressure P1 over time, issues notifications or warnings indicating that maintenance related to inspection and replacement is necessary, thereby prompting workers to perform maintenance work. This makes it possible to appropriately and easily determine the inspection and replacement timing of the sealing member 20.

[0037] As described above, the prediction device 1A of this embodiment, along with the prediction method and prediction program related to this prediction device 1A, makes it possible to predict the wear state of a seal member based on the change in pressure inside the fluid chamber caused by wear of the seal member, by providing a wear state prediction means for a shaft seal device attached to a fluid chamber in which fluid moves. This makes it possible to accurately predict the wear state of the seal member without disassembling the shaft seal device, and to appropriately determine when to replace the seal member. Furthermore, this makes it possible to reduce the burden on workers and lower costs associated with maintenance work on the shaft seal device. Furthermore, the prediction device 1A of this embodiment, as well as the prediction method and prediction program related to this prediction device 1A, are particularly suitable for use in cases where the equipment equipped with the shaft seal device is such as a slurry pump or a dispersion device, in which the fluid chamber is under negative pressure and the mixing of powder and liquid is performed.

[0038] [Second Embodiment] Figure 3 is a schematic diagram illustrating the structure of a prediction device in a second embodiment of the present invention. Figure 4 is a schematic diagram illustrating another aspect of the prediction device in a second embodiment of the present invention. As shown in Figures 3 and 4, the prediction device 1B of the second embodiment is equipped with a wear condition display unit 4 that displays the wear condition of the seal member 20, in addition to the prediction device 1A of the first embodiment. The same components as those of the first embodiment will not be described. Figures 3 and 4 also show a different structure of the wear condition display unit 4.

[0039] In this embodiment, the wear status indicator 4 is for displaying the wear status of the seal member 20. Here, "displaying the wear status of the seal member 20" includes not only displaying that the seal member 20 is worn to the point where immediate replacement is required, but also displaying that the seal member 20 is in a normal state (not worn) or that wear has begun on the seal member 20, although it has not yet reached the point of needing replacement.

[0040] An example of a wear condition display unit 4 is shown in Figure 3, which includes a display 40 connected to a wear condition prediction means 2 that displays data (prediction results) related to the wear condition of the sealing member 20 obtained by the wear condition prediction means 2, and a control unit 41 that controls the content to be displayed on the display 40 and the display specifications.

[0041] Here, the content displayed via the display 40 and control unit 41 may include, for example, the numerical value of the pressure P1 in the fluid chamber 102 measured by the pressure gauge M1 in the measurement unit 2a. Furthermore, it is preferable to change the display specifications according to the value of pressure P1 so that the operator can easily grasp the predicted result regarding the wear state of the seal member 20. For example, the value of pressure P1 may be displayed in a frame 42 on the display 40, and when the pressure P1 is within a threshold, i.e., when the seal member 20 is in a normal state (not worn), the frame 42 may be displayed in blue (or green), when the pressure P1 is decreasing, the frame 42 may be displayed in yellow, and when the pressure P1 exceeds a threshold, i.e., when it is determined that the seal member 20 is worn, the frame 42 may be displayed in red, and so on. In addition to changing the color of the frame 42, it is also possible to change the font and size of the displayed numerical value according to the value of pressure P1. Furthermore, it is preferable that the wear status indicator 4 also includes the functions related to the notification unit described above. Specifically, when the pressure P1 exceeds a threshold and the wear state of the seal member 20 has progressed considerably, requiring replacement of the seal member 20, in addition to displaying the area within the frame 42 in red, a notification or warning that maintenance such as replacement is required is displayed in the message field 43 on the display 40, prompting the operator to perform maintenance work.

[0042] In addition to the pressure P1, the contents displayed via the display 40 and the control unit 41 may also include the fluid temperature obtained by the fluid temperature measuring means and the fluid flow rate obtained by the fluid flow rate measuring means. It is preferable that these numerical values ​​be displayed according to a display specification that corresponds to the prediction of the wear state of the seal member 20, similar to the display of the pressure P1 value. Furthermore, the display 40 may also display information related to the overall operation control of the equipment 100. For example, various numerical values ​​(pressure, temperature, rotation speed, flow rate, etc.) measured for each component of the equipment 100 other than the fluid chamber 102 (pressure reducing pump, supply / discharge piping, etc.) may also be displayed. In this case, the various numerical values ​​may be displayed overlaid on a schematic diagram showing each component of the equipment 100. This makes it possible for the operator to easily grasp the overall operating status of the equipment 100, along with the predicted wear state of the seal member 20.

[0043] Another example of the wear condition display unit 4 is to provide an analog pressure gauge 44 to the pressure gauge M1, which is the wear condition prediction means 2, as shown in Figure 4. In this case, it is preferable to configure the scale portion 44a of the pressure gauge 44 to display according to the predicted result regarding the wear condition of the seal member 20, so that the operator can quickly grasp the predicted result regarding the wear condition of the seal member 20. For example, as shown in Figure 4, the scale portion 44a indicated by the needle 44b of the pressure gauge 44 can be divided into three areas, with the area representing the range of pressure values ​​when the seal member 20 is in a normal state (not worn) displayed in blue (or green), the area representing the range of pressure values ​​when the pressure P1 is decreasing displayed in yellow, and the area representing the range of pressure values ​​when the seal member 20 is judged to be worn displayed in red.

[0044] As described above, the prediction device 1B of this embodiment includes a wear condition display unit that displays prediction results regarding the wear state of the seal member, enabling operators to accurately grasp the condition and wear trend of the seal member in the shaft seal device and to make appropriate decisions regarding subsequent actions. Furthermore, this makes it possible to reduce the burden on operators and lower costs associated with maintenance work on the shaft seal device.

[0045] [Third Embodiment] Figure 5 is a schematic diagram illustrating the structure of a prediction device in a third embodiment of the present invention. Figure 6 is a schematic diagram illustrating another embodiment of the shaft sealing device and prediction device in a third embodiment of the present invention. As shown in Figures 5 and 6, the prediction device 1C of the third embodiment is equipped with a pressure detection means 3 in addition to the wear state prediction means 2 of the prediction device 1A of the first embodiment. Note that the same components as those of the first embodiment will not be described. Figures 5 and 6 also show a shaft sealing device 10 with a different structure for the pressing portion 30, illustrating the various configurations of the prediction device 1C.

[0046] The prediction device 1C of this embodiment is further provided with a pressure degree detection means that detects the degree of pressure applied by the pressing portion 30, in addition to a wear state prediction means 2 that detects pressure changes in the fluid chamber 102 and predicts the wear state of the sealing member 20. The pressure detection means 3 is for detecting the degree to which the pressing part 30 presses against the fixed-side member 21 or the rotating-side member 22. Here, "degree of pressure" refers to the magnitude of the force P applied by the pressing part 30 to bring the fixed-side member 21 and the rotating-side member 22 into close contact. Furthermore, "detection of the degree of pressure" includes not only directly measuring the magnitude of the force P, but also measuring parameters that affect the magnitude of this force P.

[0047] When the sealing member 20 wears down, the contact between the sliding surface 21a of the fixed-side member 21 and the sliding surface 22a of the rotating-side member 22 changes, which in turn causes a change in the degree of pressure (magnitude of force P) applied by the pressing part 30. Therefore, the pressure detection means 3 in this embodiment makes it possible to predict the wear state of the sealing member 20 by detecting the degree of pressure applied by the pressing part 30.

[0048] The structure of the pressing unit 30 that detects the degree of pressure using the prediction device 1C of this embodiment is not particularly limited. For example, as shown in Figure 5, there are those that use a spring mechanism 31 such as a coil spring, and as shown in Figure 6, there are those that use a pressurizing mechanism 32 using high-pressure gas. When high-pressure gas is used in the pressurizing mechanism 32, if an abnormality such as a crack occurs in the seal member 20, gas flows into the fluid chamber 102 from the housing 101 side, making it easier to detect the pressure rise. Note that the structure of the pressing part 30 shown in Figure 5 is the same as the structure of the pressing part 30 shown in Figure 1 in the first embodiment.

[0049] The pressing portion 30 shown in Figure 5 consists of a spring mechanism 31 located inside the casing 23. In Figure 5, the pressing portion 30 presses the fixed-side member 21 against the rotating-side member 22 by the elastic force of the spring mechanism 31. Note that for the pressing portion 30 using a spring mechanism 31, the structure shown in Figure 2 of the first embodiment may also be used. On the other hand, the pressing section 30 shown in Figure 6 is equipped with a pressurizing mechanism 32 that utilizes the pressure of a high-pressure gas. The pressurizing mechanism 32 only needs to be capable of pressing the sealing member 20 (fixed-side member 21 or rotating-side member 22) with the high-pressure gas, and its specific structure is not particularly limited. As an example of the pressurizing mechanism 32, for example, a structure is provided in which high-pressure gas is supplied into a sealed housing 101 via a line L1, and the high-pressure gas presses the fixed-side member 21 against the rotating-side member 22 via a communication section 23a provided in the casing 23 so as to communicate with the housing 101.

[0050] For example, as shown in Figures 5 and 6, if the pressing portion 30 applies a force P (pressure P2) from the fixed member 21 to the rotating member 22, the pressing degree detection means 3 may be a means for detecting the change in pressure P2 at that time.

[0051] One example of a means for detecting a change in pressure P2 is, for example, as shown in Figure 5, when the pressing part 30 consists of a spring mechanism 31, a pressure sensor S1 such as a piezoelectric pressure sensor is provided at a location where pressure P2 is applied by the spring mechanism 31, such as the contact area between the pressing part 30 and the fixed side member 21, to measure the pressure P2, and information related to the change in the measured value over time is collected and analyzed to directly detect the change in pressure P2. In other words, the pressing degree detection means 3 includes a measuring unit 3a equipped with a pressure sensor S1 that measures the pressure P2 by the spring mechanism 31, and a calculation unit 3b that collects and analyzes the value obtained by the measuring unit 3a (pressure sensor S1). Another example of a means for detecting changes in pressure P2 is, for example, as shown in Figure 6, when the pressing part 30 consists of a pressurizing mechanism 32 using high-pressure gas, the pressure P3 of the high-pressure gas supplied to the pressing part 30 is measured continuously or intermittently, and information regarding the change in the measured value over time is collected and analyzed to indirectly detect changes in pressure P2. In other words, the pressing degree detection means 3 includes a measuring unit 3c equipped with a pressure gauge M2 that measures the pressure P3 of the high-pressure gas supplied to the housing 101 via line L1, and a calculation unit 3d that collects and analyzes the value obtained by the measuring unit 3c (pressure gauge M2). In addition, similar to the measurement unit 2a and calculation unit 2b in the wear state prediction means 2 described above, a program necessary for data acquisition and data calculation (comparison calculation, etc.) in the measurement units 3a, 3c and calculation units 3b, 3d may be created as the prediction program in this embodiment, and the measurement units 3a, 3c and calculation units 3b, 3d may be operated by executing this prediction program.

[0052] In the pressure detection means 3, one example of collecting and analyzing information related to the change in pressure P2 (or pressure P3) over time is to predict that the wear state of the sealing member 20 is considerably advanced when the value of pressure P2 (or pressure P3) obtained by the measurement unit exceeds a preset threshold. Another example involves comparing the pressure P2 (or pressure P3) value obtained from the measurement unit with the value obtained from the previous measurement. If the amount of change exceeds a preset threshold, it can be predicted that the wear state of the sealing member 20 has progressed considerably. The threshold value set here should be at least one of the upper and lower limits of pressure P2 (or pressure P3), depending on the trend of change in pressure P2 which fluctuates due to the wear state of the sealing member 20, and both may be set. For example, if the pressing part 30 uses a pressurizing mechanism 32 with high-pressure gas, the pressure P3 of the high-pressure gas supplied to the pressing part 30 tends to increase due to the wear of the sealing member 20, so the threshold value for pressure P3 should be set to the upper limit.

[0053] Furthermore, the pressure detection means 3 may be further equipped with a notification unit that, based on the collection and analysis of information related to the change in pressure P2 (or pressure P3) over time, issues notifications or warnings indicating that maintenance related to inspection or replacement is necessary, thereby prompting the operator to perform maintenance work. In addition, the wear condition display unit 4 described above may be provided to display the wear condition of the seal member 20 based on the information obtained from the pressure detection means 3. This makes it possible to appropriately and easily determine the inspection and replacement timing of the seal member 20.

[0054] As described above, the prediction device 1C of this embodiment, along with the prediction method and prediction program related to this prediction device 1C, provides not only a wear state prediction means for predicting the wear state of the seal member in the shaft seal device, but also a pressure degree detection means. This allows for the determination of the pressure applied to the pressing portion against the fixed-side member and the rotating-side member, and enables the prediction of the wear state of the seal member from changes in this pressure degree. As a result, the wear state of the seal member can be predicted more accurately without disassembling the shaft seal device, and the timing of seal member replacement can be determined more appropriately. Furthermore, this makes it possible to further reduce the burden on workers and lower costs associated with maintenance work on the shaft seal device.

[0055] The embodiments described above are merely examples of prediction devices, prediction methods, and prediction programs. The prediction devices, prediction methods, and prediction programs according to the present invention are not limited to the embodiments described above, and the prediction devices, prediction methods, and prediction programs according to the embodiments described above may be modified without changing the gist of the claims.

[0056] For example, in addition to the wear state prediction means and pressure degree detection means related to the prediction devices 1A to 1C of this embodiment, means for understanding the wear state of the sealing member may be further combined. Such means include, for example, providing a temperature change detection means for detecting temperature changes in or around the pressing part. As the seal component wears down, friction on the sliding surface causes temperature changes not only in the seal component but also in the pressing area and its surroundings. In particular, when the seal component (fixed side component and rotating side component) is made by laminating a soft material such as carbon with a hard material such as SiC or ceramics, with the soft material on the sliding surface side, wear of the seal component exposes the hard material to the sliding surface side. At this time, since the hard materials slide against each other, frictional heat is generated more easily, resulting in a larger temperature rise in the pressing area and its surroundings. Therefore, by detecting temperature changes in the pressing area or its surroundings using a temperature change detection means, the wear state of the seal component can be determined. Here, the locations where the temperature is measured by the temperature change detection means include directly measuring the temperature of the pressing area, measuring the ambient temperature around the pressing area, and especially when slurry is flowing around the pressing area, measuring the temperature of the slurry. Furthermore, when measuring the slurry temperature, in addition to measuring the slurry temperature near the pressing area, it is also possible to measure the slurry temperature along the slurry circulation path. As described above, by further providing a temperature change detection means for detecting temperature changes in or around the pressing part, in addition to the wear state prediction means and the pressure degree detection means, it becomes possible to grasp the wear state of the sealing member with greater accuracy. [Industrial applicability]

[0057] The prediction device, prediction method, and prediction program of the present invention can be suitably used for various shaft sealing devices and various equipment equipped with various shaft sealing devices. Furthermore, the prediction device, prediction method, and prediction program of the present invention can be particularly suitably used for mechanical seals and equipment equipped with mechanical seals. [Explanation of symbols]

[0058] 1A, 1B, 1C... Prediction device, 2... Wear state prediction means, 2a... Measurement unit, 2b... Calculation unit, 3... Pressure detection means, 3a, 3c... Measurement unit, 3b, 3d... Calculation unit, 10... Shaft seal device, 20... Seal member, 21... Fixed side member, 21a... Sliding surface, 22... Rotating side member, 22a... Sliding surface, 23... Casing, 23a... Communication part, 24, 25... Support member, 30... Pressing part, 31... 32...Pressure mechanism, 4...Wear condition indicator, 40...Display, 41...Control unit, 42...Frame, 43...Message field, 44...Pressure gauge, 44a...Scale section, 44b...Needle, 100...Device, 101...Housing, 102...Fluid chamber, L1...Line, M1, M2...Pressure gauge, P...Force applied by pressing part, P1~P3...Pressure, R...Rotation axis, S1...Pressure sensor, W...Wall surface

Claims

1. A device for predicting the wear state of a sealing member, which is provided in a shaft sealing device and is located in a fluid chamber through which fluid moves and which is under negative pressure, The aforementioned shaft sealing device comprises a sealing member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, It comprises a pressing portion that presses the sliding surface of the fixed-side member and the sliding surface of the rotating-side member so that they come into close contact, A prediction device characterized by having the shaft sealing device attached and providing wear state prediction means for predicting the wear state of the seal member based on changes in the fluid pressure inside the fluid chamber.

2. The prediction device according to claim 1, further comprising a wear condition display unit for displaying the wear condition of the sealing member.

3. The wear state prediction means is characterized by comprising a fluid temperature measuring means for measuring the temperature of the fluid, as described in claim 1 or 2.

4. The wear state prediction means is characterized by comprising a fluid flow rate measuring means for measuring the flow rate of the fluid, as described in claim 1 or 2.

5. The prediction device according to any one of claims 1 to 4, further characterized by being provided with a pressure degree detection means for detecting the degree of pressure of the pressing part.

6. A method for predicting the wear state of a sealing member provided in a shaft sealing device, which is located in a fluid chamber through which fluid moves and which is under negative pressure, The aforementioned shaft sealing device comprises a sealing member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, It comprises a pressing portion that presses the sliding surface of the fixed-side member and the sliding surface of the rotating-side member so that they come into close contact, A prediction method characterized by having the shaft seal device attached and providing a wear state prediction step for predicting the wear state of the seal member based on the pressure change of the fluid inside the fluid chamber.

7. A program for predicting the wear state of a sealing member located in a fluid chamber of a shaft sealing device, where fluid moves through the interior and a negative pressure state is maintained. The aforementioned shaft sealing device comprises a sealing member having a fixed side member having a sliding surface and a rotating side member having a sliding surface, It comprises a pressing portion that presses the sliding surface of the fixed-side member and the sliding surface of the rotating-side member so that they come into close contact, A prediction program characterized by having the shaft seal device attached and performing a wear state prediction process that predicts the wear state of the seal member based on the pressure change of the fluid inside the fluid chamber.

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