Vibration diagnosis method for pump station system piping

A vibration-based diagnostic method for pump machine auxiliary piping identifies hidden issues like rust and corrosion by analyzing specific parts and comparing vibration data, ensuring timely detection and maintenance.

JP7624872B2Active Publication Date: 2025-01-31EBARA CORP
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Patent Information

Application Number
JP2021080361
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2021-05-11
Publication Date
2025-01-31
Estimated Expiration
2041-05-11

AI Technical Summary

Technical Problem

Existing methods fail to effectively diagnose abnormalities in auxiliary piping of pump machines, such as clogging, rust, or corrosion, which are not visible through exterior checks and can lead to delayed detection of issues like cracks or foreign substance collisions.

Method used

A vibration-based diagnostic method for auxiliary piping in pump machines, involving the use of hammers and vibration meters to analyze the vibration results of specific parts of the piping, including connection points and areas prone to water accumulation, to detect abnormalities.

Benefits of technology

The method allows for early detection of piping issues like rust, corrosion, and cracks by comparing current vibration data with past measurements, facilitating regular inspections and reducing the risk of system failures during floods.

✦ Generated by Eureka AI based on patent content.

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Abstract

To provide a vibration diagnostic method for pump station system piping, which allows for detecting abnormality of auxiliary equipment system piping or signs thereof at a pump station.SOLUTION: A vibration diagnostic method for pump station system piping is provided, comprising applying vibration to a specific point of auxiliary equipment system piping 100 at a pump station 1 equipped with a main pump and auxiliary equipment for driving the main pump, and diagnosing the system piping 100 on the basis of a vibration result of the system piping 100 caused by the applied vibration.SELECTED DRAWING: Figure 7
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Description

[Technical field]

[0001] The present invention relates to a vibration diagnosis method for pump station system piping. [Background technology]

[0002] Conventionally, pumping stations that operate for the purpose of flood prevention during heavy rains and the like have been known. In such pumping stations, reliable operation is required during floods, and management and monitoring of the main pump and its auxiliary equipment are essential to confirm the soundness of the entire facility. The following Patent Document 1 discloses a pump inspection method for inspecting the main pump using an image acquisition means. Also, the following Patent Document 2 discloses a pump management method for predicting the inspection and repair timing of the main pump based on the stoppage time of the main pump. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-41503 A [Patent Document 2] JP 2019-23473 A Summary of the Invention [Problem to be solved by the invention]

[0004] As in the above-mentioned conventional technology, various methods have been disclosed for the maintenance and inspection of the main pump, but the current situation is that no effective method has yet been established for the maintenance and inspection of the system piping (especially the small piping) of the auxiliary equipment. Conventionally, pumping stations have performed regular maintenance operations in preparation for drainage operations during floods, but when there is no water to drain or in an environment where drainage is not possible, only visual inspections of the appearance of the auxiliary equipment and confirmation of its operation are performed without operating the main pump.

[0005] By simply visually checking the appearance of the auxiliary equipment or checking its operation, it is difficult to notice abnormalities such as when the auxiliary equipment's system piping is starting to become clogged with dirt or rust, when the system piping is starting to become thin or pitted due to corrosion, or when the system piping is starting to crack due to aging or collision with foreign objects, and the discovery of such abnormalities may be delayed. This problem also occurs when the main pump is able to drain during maintenance operation.

[0006] The present invention has been made in consideration of the above problems, and has an object to provide a vibration diagnosis method for pump station system piping that can discover abnormalities or signs of abnormalities in the system piping of auxiliary machinery at a pump station. [Means for solving the problem]

[0007] One embodiment of the present invention provides a vibration diagnosis method for pump station system piping, in which a main pump and an auxiliary machine that operates the main pump are provided at a pump station, and a specific location of the auxiliary machine's system piping is vibrated, and the system piping is diagnosed based on the vibration results of the vibration.

[0008] In the above-mentioned vibration diagnosis method for pump station system piping, the system piping may include at least one of system piping of a cooling water system that supplies cooling water to a drive device of the main pump, system piping of a water filling system that fills the main pump with priming water, system piping of a seal water system that supplies seal water liquid to a shaft seal portion of the main pump, system piping of a compressed air system that supplies compressed air to the drive device of the main pump, and system piping of a drainage system of the pump station.

[0009] In the above-mentioned vibration diagnosis method for a pump station system piping, the system piping may be diagnosed by comparing a vibration result of the system piping with a vibration result of the system piping measured in the past.

[0010] In the above-described vibration diagnosis method for a pump station system piping, the diagnosis of the system piping may be performed when the pump station is out of operation or during maintenance operation of the pump station.

[0011] In the above-mentioned vibration diagnosis method for pump station system piping, the vibration points at which the system piping is vibrated may include at least one of a connection between pipes of the system piping, a space between the connection and an adjacent connection, a piping support supporting the system piping, and a space between the piping support and an adjacent piping support.

[0012] In the above-described vibration diagnosis method for a pump station system piping, the specific portion of the system piping may include a portion of the system piping where water constantly accumulates.

[0013] In the above-described vibration diagnosis method for a pump station system piping, the specific location of the system piping may include a location where an installation position is the lowest in the system piping.

[0014] In the above-mentioned vibration diagnosis method for a pump station system piping, the diagnosis of the system piping may be performed in each of a state where the system piping is filled with water and a state where the system piping is empty.

[0015] In the above-mentioned vibration diagnosis method for a pump station system piping, the diagnosis of the system piping may be performed by frequency analysis of vibration results of the system piping. Effect of the Invention

[0016] According to the above aspect of the present invention, it is possible to provide a vibration diagnosis method for pump station system piping, which is capable of discovering abnormalities or signs of abnormalities in the system piping of auxiliary machines in a pump station. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is an overall configuration diagram of a pump station according to an embodiment. [Diagram 2] FIG. 2 is an explanatory diagram showing a specific location of system piping in a cooling water system according to an embodiment. [Diagram 3] FIG. 2 is an explanatory diagram showing a specific location of system piping of a seal water system according to one embodiment. [Figure 4]4 is a cross-sectional view taken along line IV-IV in FIG. 3. [Diagram 5] FIG. 2 is an explanatory diagram showing a specific location of system piping in a water-filled system according to one embodiment. [Figure 6] 6 is a cross-sectional view taken along line VI-VI in FIG. 5. [Figure 7] FIG. 2 is an explanatory diagram showing a vibration diagnosis method for a pump station system piping according to an embodiment. [Figure 8] FIG. 2 is an explanatory diagram showing preferred vibration points in a vibration diagnosis method for a pump station system piping according to an embodiment. [Figure 9] 11 is a graph showing a frequency analysis of the measurement results (initial measurement data) of a measuring device according to one embodiment. [Figure 10] 11 is a graph showing a frequency analysis of the measurement results (measurement data when an abnormality occurs) of a measuring device according to one embodiment. [Figure 11] FIG. 11 is an explanatory diagram showing a vibration diagnosis method for a pump station system piping according to a modified example of an embodiment. [Figure 12] FIG. 11 is a diagram for explaining a vibration diagnosis method for a pump station system piping according to another modified example of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, a vibration diagnosis method for a pump station system piping according to an embodiment of the present invention will be described with reference to the drawings. In the following description, a pump station that operates for the purpose of preventing flooding during heavy rain or the like will be exemplified as an application example of the present invention.

[0019] FIG. 1 is an overall configuration diagram of a pump station 1 according to one embodiment. 1 includes a plurality of main pumps 10 and a plurality of auxiliary machines 20 that operate the main pumps 10. The pump station 1 includes four horizontal shaft pumps as the main pumps 10. The pump station 1 also includes, as the auxiliary machines 20, a vacuum pump 21, a fuel transfer pump 22, an air compressor 23, a cooling water pump 24, a seal water pump 25, and the like.

[0020] The main pump 10 is a horizontal shaft pump in which an impeller is attached to a main shaft extending in a horizontal direction. The main pump 10 may be a vertical shaft pump in which an impeller is attached to a main shaft extending in a vertical direction. The main pump 10 is driven by a drive device 15. The drive device 15 includes a rotating machine 4 equipped with an internal combustion engine (such as a diesel engine) and a reducer 5 connected to the rotating machine 4.

[0021] A reducer 5 is connected to the drive shaft of the rotating machine 4, and a main shaft of a main pump 10 is connected to the reducer 5. By driving the rotating machine 4, the main shaft of the main pump 10 rotates via the reducer 5, and the water in a suction tank (not shown) is pumped up by the rotation of an impeller attached to the main shaft, and the water is discharged into a discharge tank (not shown).

[0022] The vacuum pump 21 constitutes a water-filling system 30 that sucks air from the main pump 10 and fills the main pump 10 with priming water when the main pump 10 is started. The vacuum pump 21 is connected to the main pump 10 via system piping 30a. The system piping 30a is provided with a water-filling detector 14 for detecting whether the main pump 10 is full of priming water, and an intake valve 31 (motor valve or solenoid valve) for opening and closing the system piping 30a.

[0023] The vacuum pump 21 is driven by an electric motor 21a. The vacuum pump 21 is, for example, a water-sealed vacuum pump, and is connected to a water supply pipe 32 for supplying makeup water on its intake side, and to a discharge pipe 33b for discharging the sucked air on its exhaust side. The water supply pipe 32 is connected to a water tank 34, and is provided with a water supply valve 35 (usually a manual valve) for opening and closing the water supply pipe 32.

[0024] The fuel transfer pump 22 pumps up fuel for the rotating machine 4. This fuel transfer pump 22 is driven by an electric motor 22a. The fuel transfer pump 22 is provided in a fuel supply pipe 40. In the fuel supply pipe 40, the fuel is pumped up from an underground oil tank 6 that stores fuel to a fuel dispense tank 7 installed at a predetermined height above ground by driving the fuel transfer pump 22, and the fuel is supplied from the fuel dispense tank 7 to the rotating machine 4. By storing fuel in the fuel dispense tank 7, it is possible to supply fuel to the rotating machine 4 at a required supply pressure even while the fuel transfer pump 22 is not driven.

[0025] The air compressor 23 constitutes a compressed air system 50 that supplies compressed air to the rotating machine 4 of the main pump 10. The air compressor 23 is connected to the air tank 8 via system piping 50a. The air compressor 23 fills the air tank 8 with compressed air (starting air) for starting the rotating machine 4. The air compressor 23 is driven by an electric motor 23a. In the system piping 50a, compressed air compressed by the driving of the air compressor 23 fills the air tank 8, and the compressed air is supplied from the air tank 8 to the rotating machine 4. By storing compressed air in the air tank 8, the compressed air can be supplied to the rotating machine 4 to start it up.

[0026] The cooling water pump 24 constitutes a cooling water system 60 that supplies cooling water to the drive unit 15 that drives the main pump 10. The cooling water pump 24 is driven by an electric motor 24a. The cooling water pump 24 is connected to the heat exchanger 9 of the drive unit 15 via a system piping 60a. The heat exchanger 9 shown in FIG. 9 is provided in the rotating machine 4, but may also be provided in the reduction gear 5. In the system piping 60a, cooling water is pumped up from a cooling water tank 61 by the driving of the cooling water pump 24, and the cooling water is supplied to the heat exchanger 9 of each drive unit 15. In the system piping 60a, the cooling water supplied to the heat exchanger 9 returns to the cooling water tank 61 and circulates.

[0027] Raw water (river water, etc.) is supplied to the cooling water tank 61 via system piping 60b. A water intake pump 72 is provided in the system piping 60b. This water intake pump 72 is driven by an electric motor 72a. In the system piping 60b, raw water is taken in from a water intake pit 71 by driving the water intake pump 72, and the raw water from which foreign matter such as sand and mud has been removed by filtering devices such as a strainer 73 and a sand separator 74 is supplied to the cooling water tank 61.

[0028] In addition to the cooling water pump 24, the cooling water tank 61 is provided with a seal water pump 25. The seal water pump 25 constitutes a seal water system 80 that supplies seal water liquid to the shaft seal portion 16 of the main pump 10. The seal water pump 25 is driven by an electric motor 25a. The seal water pump 25 is connected to the shaft seal portion 16 of the main pump 10 via system piping 80a. The system piping 80a is provided with a seal water valve 81 (motor valve or solenoid valve) that opens and closes a branch pipe 81a connected to the shaft seal portion 16 of each main pump 10. In the system piping 80a, the seal water liquid is pumped up from the cooling water tank 61 by driving the seal water pump 25, and the seal water liquid is supplied to the shaft seal portion 16 of each main pump 10.

[0029] FIG. 2 is an explanatory diagram showing a specific location W of a system piping 60a of a cooling water system 60 according to one embodiment. As shown in Fig. 2, system piping 60a of cooling water system 60 has an upstream piping from cooling water tank 61 to drive unit 15 (heat exchanger 9) in the building of pump station 1, and a downstream piping from drive unit 15 (heat exchanger 9) to cooling water tank 61. Note that drive unit 15 shown in Fig. 2 is installed on installation floor 2 in the same building as main pump 10 (in the case of a horizontal shaft pump).

[0030] The upstream piping of the system piping 60a is provided with, in this order from the upstream side, a cooling water pump 24, a check valve 62, and an on-off valve 63. Therefore, while the cooling water pump 24 is stopped, a specific location W where water always accumulates is generated downstream (secondary side) of the check valve 62 in the upstream piping of the system piping 60a unless the water is drained.

[0031] An automatic air vent valve 64 is provided in the downstream piping of the system piping 60a to prevent the water flow from continuing due to the siphon principle after the cooling water pump 24 is stopped. Therefore, the downstream piping of the system piping 60a is filled with water while the cooling water pump 24 is operating, and is empty while the cooling water pump 24 is stopped.

[0032] Fig. 3 is an explanatory diagram showing a specific location W of the system piping 80a of the seal water system 80 according to one embodiment. Fig. 4 is a cross-sectional view taken along line IV-IV shown in Fig. 3. As shown in Figures 3 and 4, a portion of the system piping 80a of the sealing water system 80 is placed within a pit 2a provided on the installation floor 2 within the building of the pump station 1 in order to ensure a maintenance passage within the building.

[0033] As shown in Fig. 3, the pit 2a is a groove that is lower than the floor surface of the installation floor 2, and its opening is covered by a pit cover 2b. As shown in Fig. 4, the system piping 80a is bent in a U-shape and arranged in the pit 2a. Therefore, in the system piping 80a, a specific location W where water always accumulates is generated at least in the part arranged in the pit 2a while the seal water pump 25 is stopped, unless the water is drained. Note that the part of the system piping 80a arranged in the pit 2a also corresponds to the specific location L where the installation position is the lowest in the system piping 80a.

[0034] Fig. 5 is an explanatory diagram showing a specific location L of the system piping 30a of the full-water system 30 according to one embodiment. Fig. 6 is a cross-sectional view taken along line VI-VI shown in Fig. 5. 5, the system piping 30a of the full-water system 30 is connected to the upper part of the main pump 10. In the system piping 30a, air is sucked in by the vacuum pump 21, and when the main pump 10 becomes full, the float of the full-water detector 14 blocks the air sucking.

[0035] 6, in order to ensure a maintenance passageway within the building, this system piping 30a may also be placed in a pit 2a provided in the installation floor 2. The portion of the system piping 30a placed in the pit 2a corresponds to a specific location L having the lowest installation position in the system piping 30a.

[0036] Incidentally, when the float of the full water detector 14 cuts off the water, air containing a small amount of water may be sucked in just before the water is cut off, causing water to enter the system piping 30a. In addition, due to changes in temperature, humidity, and pressure, the saturated vapor pressure may be exceeded, and water may be generated in the system piping 30a. Such water tends to accumulate at a specific point L, which is the lowest installed position in the system piping 30a.

[0037] Next, we will explain a vibration diagnosis method for pump station system piping (hereinafter referred to as this method) that can effectively diagnose abnormalities and their precursors at specific locations W and L where water constantly accumulates and / or where water is likely to accumulate and rust and corrosion are likely to occur, as described above.

[0038] FIG. 7 is an explanatory diagram showing a vibration diagnosis method for a pump station system piping according to one embodiment. As shown in FIG. 7, in this method, an operator 200 vibrates specific points W, L of the system piping 100 of the above-mentioned auxiliary machine 20, and diagnoses the system piping 100 based on the vibration result of the system piping 100 due to the vibration.

[0039] 1 described above, the system piping 100 to be diagnosed includes at least one of the system piping 60a of the cooling water system 60 that supplies cooling water to the drive unit 15 of the main pump 10, the system piping 30a of the water filling system 30 that fills the main pump 10 with priming water, the system piping 80a of the seal water system 80 that supplies seal water liquid to the shaft seal portion 16 of the main pump 10, the system piping 50a of the compressed air system 50 that supplies compressed air to the drive unit 15 of the main pump 10, and the system piping of the drainage system (not shown) of the pump station 1. The system piping of the drainage system includes the on-site drainage piping when a floor drain pump that drains miscellaneous water in the pump station 1 is installed, and the drainage piping for draining drains from the various pumps of the main pump 10 and the auxiliary equipment 20.

[0040] 7, in this method, a worker 200 holds a hammer 201 and a measuring device 202, strikes the system piping 100 with the hammer 201, and measures the striking sound or vibration by the measuring device 202. The shape, use, and characteristics of the hammer 201 should be selected to be suitable for striking the system piping 100. The measuring device 202 may be a sound level meter that measures the striking sound emitted from the system piping 100, or a vibration meter that measures the vibration of the system piping 100, and the performance (precision) of the measuring device should be selected to be suitable for measuring the striking sound and vibration of the system piping 100.

[0041] The diameter, material, shape, and thickness of the system piping 100 are not specified, but most of the system piping 100 is carbon steel pipes such as SGP, SGPW, STPG, etc., stainless steel pipes such as SUS pipes, copper pipes, etc. Also, the system piping 100 is a circular pipe (so-called small pipe) with a diameter of about 8A to 300A (8 mm to 300 mm) according to the JIS standard.

[0042] The system piping 100 includes a connection portion 101 for connecting the pipes to each other. The connection portion 101 shown in Fig. 7 is a flange connection, but may be a screw connection or a welded connection. Such a system piping 100 is supported by a plurality of pipe supports 102. Next, a preferred position of the vibration point P for vibrating the system piping 100 in this method will be described.

[0043] FIG. 8 is an explanatory diagram showing a preferable vibration point P in the vibration diagnosis method for a pump station system piping according to one embodiment. As shown in FIG. 8, it is preferable that the vibration points P for vibrating the system piping 100 include at least one of vibration points P1 to P4.

[0044] The excitation point P1 is a connection 101 between pipes of the system piping 100. The excitation point P2 is between the connection 101 and the next adjacent connection 101. Specifically, the excitation point P2 should be located at a position of A / 2, where A is the distance from the connection 101 to the next adjacent connection 101. The excitation point P1 directly vibrates the connection 101 where rust, corrosion, etc. are relatively likely to occur, making it easier to find abnormalities or signs of such problems. In addition, the excitation point P2 is somewhat away from the connection 101, making it easier to find rust, corrosion, etc. other than at the connection 101.

[0045] The excitation point P3 is a pipe support 102 that supports the system piping 100. The excitation point P4 is between the pipe support 102 and the adjacent pipe support 102. Specifically, the excitation point P4 may be located at a position of B / 2, where B is the distance from the pipe support 102 to the adjacent pipe support 102. Since the system piping 100 is fixed at the excitation point P3 by the pipe support 102, vibration can be measured under the same conditions. In addition, since the excitation point P4 is between the pipe supports 102, the amplitude of the system piping 100 is likely to be large, making it easier to measure the sound and vibration of the system piping 100 with the measuring instrument 202.

[0046] Fig. 9 is a graph showing a frequency analysis of the measurement results (initial measurement data) of measuring instrument 202 according to one embodiment. Fig. 10 is a graph showing a frequency analysis of the measurement results (measurement data when an abnormality occurs) of measuring instrument 202 according to one embodiment. Figs. 9 and 10 show examples of the results of FFT analysis with frequency on the horizontal axis and sound pressure level on the vertical axis. As shown in Figs. 9 and 10, diagnosis of the system piping 100 can be easily performed by performing frequency analysis and comparison of the vibration results of the system piping 100.

[0047] As shown in Figures 9 and 10, when observing the frequency component (dominant frequency) of a certain peak surrounded by reference symbol 300, it is clearly higher in Figure 10 than in Figure 9, and it is clear that some kind of abnormality has occurred in Figure 10. Note that since the natural frequency of the system piping 100 differs depending on each plant and each location, it is advisable to diagnose an abnormality or a sign of an abnormality in the system piping 100 by comparing with initial measurement data as shown in Figure 9.

[0048] When a blockage occurs in the system piping 100, a change occurs at a specific frequency, or the vibration waveform itself changes. The measurement data at the time of occurrence of the abnormality may change, for example, by increasing or decreasing the sound pressure level at one or more of the dominant frequencies of the initial measurement data shown in Fig. 9. Furthermore, the measurement data at the time of occurrence of the abnormality may change or disappear at a dominant frequency compared to the initial measurement data shown in Fig. 9. By observing the above-mentioned changes, it becomes possible to discover abnormalities in the system piping 100 and their precursors.

[0049] In this manner, the vibration diagnosis method for pump station system piping according to the present embodiment described above vibrates a specific location of the system piping 100 of the auxiliary equipment 20 in a pump station 1 provided with the main pump 10 and the auxiliary equipment 20 that operates the main pump 10, and diagnoses the system piping 100 based on the vibration result of the system piping 100 caused by the vibration. According to this method, it is possible to find abnormalities or signs of abnormalities in the system piping 100 that could not be found by conventional visual inspection of the appearance of the auxiliary equipment 20 or by checking the operation of the auxiliary equipment 20 alone.

[0050] In this embodiment, the system piping 100 includes at least one of the system piping 60a of the cooling water system 60 that supplies cooling water to the drive device 15 of the main pump 10, the system piping 30a of the water filling system 30 that fills the main pump 10 with priming water, the system piping 80a of the seal water system 80 that supplies seal water liquid to the shaft seal portion 16 of the main pump 10, the system piping 50a of the compressed air system 50 that supplies compressed air to the drive device 15 of the main pump 10, and the system piping of the drainage system of the pump station 1. These are the system piping 100 that are prone to rust and corrosion, so the present method makes it easier to find abnormalities and their precursors.

[0051] In addition, in this embodiment, the system piping 100 is diagnosed by comparing the vibration result of the system piping 100 with the vibration result of the system piping 100 measured in the past. For example, by comparing the above-mentioned initial measurement data with the data when an abnormality occurs during inspection, differences and changes from the initial measurement data can be found, and abnormalities such as clogging due to foreign matter or rust, thinning due to corrosion, and cracks can be found early, making it possible to manage trends in the system piping 100. Furthermore, if certain characteristics can be found in each abnormal state such as clogging, thinning due to corrosion, and cracks in the system piping 100 or in the analysis results at an intermediate stage, it becomes easier to find abnormalities and their precursors in the system piping 100 as teacher data.

[0052] Furthermore, in this embodiment, diagnosis of the system piping 100 may be performed when the pump station 1 is shut down or during maintenance operation of the pump station 1. According to this method, for example, the vibration diagnosis using the hammer 201 described above may be performed about once a month in a pump station 1 that does not allow maintenance operation, and may be performed in accordance with the maintenance operation period in a pump station 1 that allows maintenance operation, thereby making it possible to periodically diagnose the system piping 100.

[0053] In this embodiment, the vibration points P that vibrate the system piping 100 include at least one of the connection parts 101 between the pipes of the system piping 100, the space between the connection part 101 and the adjacent connection part 101, the pipe support 102 that supports the system piping 100, and the space between the pipe support 102 and the adjacent pipe support 102. In order to vibrate the same position, it is preferable to mark the vibration points P with a seal, paint, or the like to improve the accuracy of the vibration diagnosis.

[0054] At excitation point P1, rust, corrosion, and the like are relatively likely to occur at connection 101, so it is easy to find abnormalities and signs of such at excitation point P1. At excitation point P2, which is somewhat away from connection 101, it is easy to find rust, corrosion, and the like at parts other than connection 101. At excitation point P3, the system piping 100 is fixed by piping support 102, so vibration can be measured under the same conditions. At excitation point P4, which is between piping supports 102, the amplitude of the system piping 100 becomes large, making it easy to measure the sound and vibration of the system piping 100 with measuring instrument 202.

[0055] Furthermore, by setting two or more excitation points P, it is possible to diagnose the difference between each measurement value (frequency change or attenuation) and identify the location of the abnormality. Also, by capturing the trend of change in the measurement value in accordance with the change in each measurement value (change over time), more accurate diagnosis is possible. Note that by attaching a measuring device 202 to one of the excitation points P (for example, excitation point P3 which can utilize the piping support 102) and sequentially changing the excitation points P1 to P4, it is possible to identify the abnormality from the difference in response time.

[0056] In the present embodiment, the specific locations of the system piping 100 include a specific location W where water always accumulates in the system piping 100. This method makes it possible to diagnose abnormalities and their precursors in the specific location W where rust or corrosion is particularly likely to occur.

[0057] In the present embodiment, the specific locations of the system piping 100 include a specific location L that is the lowest in the system piping 100. This method makes it possible to diagnose abnormalities and their signs in the specific location L where rust and corrosion are particularly likely to occur.

[0058] In this embodiment, the diagnosis of the system piping 100 may be performed both when the system piping 100 is filled with water and when the system piping 100 is empty. This is because characteristics emerge when the system piping 100 is filled with water and when it is empty or when there is air in it. For example, by vibrating the system piping 100, the presence or absence of water can be determined. In other words, it can be determined that there is a water puddle or an air puddle in the system piping 100. In addition, when an abnormality occurs in the system piping 100, for example, no characteristics emerge when there is water, but characteristics emerge when the water is drained and the system piping is empty, or vice versa.

[0059] In the present embodiment, the diagnosis of the system piping 100 is performed by frequency analysis of the vibration results of the system piping 100. This is because the diagnosis of the system piping 100 is performed by frequency analysis of the vibration results of the system piping 100, which makes it easier to compare. Note that the frequency analysis may be performed in real time or / and FFT analysis to extract differences and points of change.

[0060] Although preferred embodiments of the present invention have been described and illustrated above, it should be understood that these are illustrative of the present invention and should not be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the present invention. Thus, the present invention should not be considered as limited by the foregoing description, but rather by the scope of the claims.

[0061] FIG. 11 is an explanatory diagram showing a vibration diagnosis method for a pump station system piping according to a modified example of the embodiment. 11, an operator 200 drops a weight 211 onto the system piping 100 to vibrate specific points W and L, and diagnoses the system piping 100 based on the vibration of the system piping 100 caused by the vibration. In this method, in order to apply a certain amount of impact to the system piping 100, a cylindrical portion 210 is attached to the system piping 100, and the weight 211 is dropped from a fixed height on the upper end of the cylindrical portion 210. This allows the system piping 100 to be vibrated and diagnosed under the same conditions.

[0062] FIG. 12 is an explanatory diagram showing a vibration diagnosis method for a pump station system piping according to another modified example of the embodiment. 12, an operator 200 contacts a vibration speaker 220 with the system piping 100 to vibrate specific locations W and L, and diagnoses the system piping 100 based on the vibration results of the system piping 100. In this method, a constant vibration is applied by the vibration speaker 220, so that the system piping 100 can be vibrated and diagnosed under the same conditions.

[0063] In addition, for example, in the above embodiment, specific locations of the system piping 100 are exemplified by specific location W where water always accumulates in the system piping 100 and specific location L which is the lowest installed location in the system piping 100, but vibration diagnosis may also be performed on other locations such as curved pipe sections and reducer pipe sections.

[0064] Also, for example, in the system piping 100 filled with water, since it may be affected by the wave motion transmitted through the fluid, the location of the abnormality may be determined by opening and closing valves provided in the system piping filled with water. Since the system piping 100 of the water system is basically normally filled with water, it is advisable to perform a diagnosis by dividing a specific section during vibration diagnosis by closing valves. By making the section closed, the diagnosis can be performed without being affected by the wave motion transmitted through the internal fluid. Also, instead of valves, a vibration insulating part such as a rubber flex may be provided in the middle of the piping to perform a divided diagnosis. This makes it easier to identify the abnormality inside the piping, since the vibration of the surface of the system piping 100 is not transmitted, but is propagated from the fluid. [Explanation of symbols]

[0065] 1...pump station, 2...installation floor, 2a...pit, 2b...pit cover, 4...rotating machine, 5...reduction gear, 6...underground oil tank, 7...fuel tank, 8...air tank, 9...heat exchanger, 10...main pump, 14...full water detector, 15...drive unit, 16...shaft seal, 20...auxiliary equipment, 21...vacuum pump, 21a...motor, 22...fuel transfer pump, 22a...motor, 23...air compressor, 23a...motor, 24...cooling water pump, 24a...motor, 25...sealing pump, 25a...motor, 30...full water system, 30a...system piping, 31...intake valve, 32...water supply pipe, 33b...discharge pipe, 34...water tank, 35...water supply valve, 40...fuel supply piping, 50...compressed air system, 50 a...system piping, 60...cooling water system, 60a...system piping, 60b...system piping, 61...cooling water tank, 62...backflow prevention valve, 63...opening / closing valve, 64...automatic air vent valve, 71...water intake pit, 72...water intake pump, 72a...motor, 73...strainer, 74...sand separator, 80...sealing water system, 80a...system piping, 81...sealing water valve, 81a...branch pipe, 100...system piping, 101...connection, 102...piping support, 200...worker, 201...hammer, 202...measuring instrument, 210...tube, 211...weight, 220...vibration speaker, L...specific location, P...excitation point, P1...excitation point, P2...excitation point, P3...excitation point, P4...excitation point, W...specific location

Claims

1. A vibration diagnosis method for pump station system piping, in which a main pump and an auxiliary machine that operates the main pump are provided, comprising the steps of: vibrating a specific location of a system piping of the auxiliary machine, and diagnosing abnormal locations inside the system piping based on the vibration results of the system piping caused by the vibration.

2. The vibration diagnosis method for pump station system piping as described in claim 1, characterized in that the specific locations of the system piping include locations in the system piping where water always accumulates or where water is prone to accumulate.

3. The system piping includes: A system piping of a cooling water system for supplying cooling water to a drive device of the main pump; A system piping for a water-filling system for filling the main pump with priming water; A system piping for a seal water system that supplies seal water liquid to a shaft seal portion of the main pump; A system piping for a compressed air system that supplies compressed air to the drive device of the main pump; 3. The vibration diagnosis method for pump station system piping according to claim 1 or 2, wherein at least one of the system piping of a drainage system of the pump station is included.

4. The vibration diagnosis method for a pump station system piping according to any one of claims 1 to 3, characterized in that the system piping is diagnosed by comparing a vibration result of the system piping with a vibration result of the system piping measured in the past.

5. The vibration diagnosis method for a pump station system piping according to any one of claims 1 to 4, characterized in that the diagnosis of the system piping is performed when the pump station is shut down or when the pump station is under maintenance operation.

6. The vibration points for vibrating the system piping include: A connection portion between the pipes of the system piping; Between the connection portion and the adjacent connection portion, A piping support for supporting the system piping; The vibration diagnosis method for pump station system piping according to any one of claims 1 to 5, characterized in that at least one of between the pipe support and an adjacent pipe support is included.

7. The vibration diagnosis method for a pump station system piping according to any one of claims 1 to 6, characterized in that the diagnosis of the system piping is performed in both a state in which the system piping is filled with water and a state in which the system piping is empty.

8. 8. The method for vibration diagnosis of a pump station system piping according to claim 1, wherein the diagnosis of the system piping is performed by frequency analysis of vibration results of the system piping.

9. In a pump station in which a main pump and an auxiliary machine for operating the main pump are provided, a specific portion of a system piping of the auxiliary machine is excited, and the system piping is diagnosed based on the vibration result of the excitation, A vibration diagnosis method for a pump station system piping, characterized in that the diagnosis of the system piping is performed in both a state where the system piping is filled with water and a state where the system piping is empty.

Citation Information

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