JPH04337180A - Motor-operated valve diagnosing device - Google Patents

Abstract

PURPOSE:To provide a motor-operated valve diagnosing device which diagnoses a motor-operated valve and selects the motor-operated valve so that the motor- operated valve having the high possibility of abnormality is inspected with priority. CONSTITUTION:A motor-operated valve diagnosing device 12 comprises a vibration detecting means 14 attached to a motor-operated valve 1 and a frequency analyzing means 20 to analyze the frequency of vibration detected by a vibration detecting means 14. The diagnosing device is also provided with a peak probing means 21 to determine a peak valve from a frequency analyzing result and a comparison deciding means 22 to compare a peak valve determined by the peak probing means 21 with a peak allowable value and decide that abnormality occurs when the peak value exceeds the peak allowable value. Further, a display means 23 to display a result therefrom is provided.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric valve diagnostic device for diagnosing abnormalities in electric valves.

0002

2. Description of the Related Art In the case of valves used in plants where many valves are used, such as nuclear power plants, all valves are required to operate normally without failure. However, this requires measures to prevent failures in advance. Electrically operated valves in particular are susceptible to vibration and tend to fail frequently. This is because wear and tear on the drive unit due to vibrations greatly affects the operability of the valve. Nuclear power plants use a large number of electrically operated valves, so these electrically operated valves are inspected on a regular basis. Inspection methods include disassembling and inspecting the motor-operated valve, measuring various parameters of the motor-operated valve using a portable measuring device, and having humans judge the measured data to diagnose the health of the motor-operated valve. I was going.

0003

[Problems to be Solved by the Invention] As mentioned above, in order to diagnose the health of an electric valve, it is necessary to periodically disassemble and inspect it, or to manually judge the measurement data measured using a portable measuring device. Was.

By the way, in the case of large-scale plants such as nuclear power plants, a large number of electric valves are used, so diagnosing the health of the electric valves as described above requires a huge amount of labor and time. I didn't like it sexually. This problem can be solved by selecting the motor-operated valve to be inspected from a large number of motor-operated valves, but this selection method is not clearly defined and is only carried out sequentially on a regular schedule. Ta. Furthermore, although a portable measuring device is an effective means for testing the operating characteristics of an electric valve, actual diagnosis is performed by humans using data obtained from the portable measuring device. Moreover, this diagnosis was made by a small number of experts based on their knowledge based on experience, and was only possible by a limited number of people.

The present invention has been made in view of the above-mentioned problems, and is an electrically operated valve that diagnoses abnormalities in electrically operated valves and selects electrically operated valves so that electrically operated valves with a high possibility of abnormality are inspected preferentially. The purpose is to provide a valve diagnostic device. [Structure of the invention]

[0006]

[Means for Solving the Problems] In order to achieve the above object, an electric valve diagnostic device according to the present invention includes a vibration detection means attached to an electric valve for detecting vibration, and a vibration detection means for detecting vibrations detected by the vibration detection means. A frequency analysis means for analyzing a frequency to obtain a frequency component, a peak search means for obtaining a peak value specific to the electric valve from the frequency component obtained by the frequency analysis means, and a predetermined peak value obtained from the peak search means. and a display means for displaying the result determined by the comparison and determination means. It is characterized by comprising: a vibration detection means attached to the electric valve for detecting vibration; an amplitude distribution calculation means for calculating the amplitude distribution of the vibration detected by the vibration detection means; a peak search means for calculating the peak amplitude value from the amplitude distribution obtained by the peak search means; and a peak search means for calculating the difference between the peak amplitude value obtained by the peak search means and an amplitude tolerance value which is a predetermined amplitude tolerance value specific to the electric valve. It is characterized by comprising a priority determining means for determining the priority of an inspection target based on its size, and a display means for displaying the results obtained by the priority determining means.

[0007]

[Operation] In the electric valve diagnosis device configured in this way, vibration of the electric valve is detected, the frequency component of this vibration is determined, a peak value specific to the electric valve is determined from this frequency component, and this peak value and the By comparing the predetermined electric valve specific peak tolerance values, it is possible to diagnose an abnormality in the electric valve.

[0008] Furthermore, the amplitude distribution is determined from the vibration of the electric valve,
The electric valve can be monitored by determining the peak amplitude value from this amplitude distribution and comparing this amplitude value with a predetermined permissible amplitude value specific to the electric valve. Further, by determining the priority based on the magnitude of the difference between the peak amplitude value and the above-mentioned allowable value, it is possible to select the electric valve to be inspected.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an electric valve diagnostic device according to an embodiment of the present invention, and FIG. 2 is a schematic structural diagram showing the structure of the electric valve. First, the structure of the electric valve will be explained using FIG. 2.

In FIG. 2, the electric valve 1 includes a valve drive section 2 that drives the valve, and a motor 3 that provides driving force to the valve drive section 2.
and a valve section 6 consisting of a valve body 4 and a valve box 5 that control fluid.
It is mainly composed of. The rotational force generated by the motor 3 is transmitted to the worm gear 9 via the motor pinion 7 of the valve drive unit 2 and the worm 8 by meshing gears. Worm gear 9 rotates dry sleeve 10. A threaded portion is formed inside the dry sleeve 10, into which the valve stem 11 is screwed, and as the dry sleeve 10 rotates, the valve stem 11 is moved in the vertical direction. The above is the structure and operating principle of the valve drive section 3. Valve drive part 3
A valve body 4 is attached to one end of a valve rod 11 driven by the valve body 4. The valve body 4 moves up and down to control the fluid, and a valve box 5 surrounding the valve body 4 maintains internal pressure.

[0011] In the electric valve configured as described above, as deterioration occurs over time, there is a possibility that rotating parts such as the motor pinion 7 and the worm gear 9 may wear out or break due to vibration, which may lead to malfunction of the valve. It may cause.

As shown in FIG. 1, the motor-operated valve diagnostic device 12 includes an acceleration sensor 14 attached to the connection section 13 between the valve drive section 2 and the motor 3 of the motor-operated valve 1, detects vibrations, and transmits a vibration signal 30. ing. Furthermore, this transmitted vibration signal 30 is amplified by an amplifier 15 and converted into an analog/digital (A/D) signal.
The converter 16 converts the analog signal into a digital signal. FIG. 3 shows an example of the raw waveform of the detected vibration signal 30. The vibration signal converted into a digital signal is then transmitted by a multiplex transmitter 17 and input to a diagnostic processor 19 via a receiver 18 .

In the diagnostic processor 19, a frequency analyzer 20 performs frequency analysis of the input vibration signal. This frequency analysis is generally performed by converting a time function into a frequency function using fast Fourier transform.

At this time, since the acceleration sensor 14 is attached to the connecting portion 13 between the valve drive section 2 and the motor 3, vibrations of both the valve drive section 2 and the motor 3 can be detected. As a result, a frequency component unique to the electric valve is obtained, which has a peak in the vibration frequency of the motor pinion, worm gear, motor speed, etc. The peak values of the frequency components specific to these electric valves are determined by the peak probe 21. The normal values of these peak values are obtained through operational tests of the motor-operated valve, and from these normal peak values, the permissible range of peaks specific to the motor-operated valve, that is, the permissible peak-specific peak value of the motor-operated valve, is determined in advance. . Next, the comparator 22 compares the peak value obtained by the peak probe 21 described above with the electric valve specific peak tolerance value, and if the measured peak value exceeds the peak tolerance value, it is determined that there is an abnormality. . FIGS. 4 and 5 are relational diagrams showing frequency components in normal and abnormal times of the frequency analysis results by the electric valve diagnostic device according to this embodiment, and will be described in detail. In FIGS. 4 and 5, the horizontal axis shows frequency (Hz), and the vertical axis shows vibration analysis values. Further, the peak permissible value Vc of the frequency component due to the meshing of the worm gear is shown by a dotted line.

FIG. 4 shows frequency components during normal operation, and three peaks appear in these frequency components. In descending order of frequency (Hz), the first peak A is the rotational speed component of the dry sleeve, the second peak B is the meshing frequency component of the worm gear, and the third peak C is the meshing frequency component of the motor pinion. Considering only the peak allowable value due to worm gear engagement, the peak value at peak B is the peak allowable value Vc
Since it does not exceed , it is judged to be normal. Also,
In FIG. 5, frequency components at a certain measurement time are shown, and as in the case of FIG. 4, three peaks appear.
In descending order of frequency (Hz), the first peak D is the rotational speed component of the dry sleeve, the second peak E is the meshing frequency component of the worm gear, and the third peak F is the meshing frequency component of the motor pinion. . Here, the peak E of the meshing frequency component of the worm gear is determined to be abnormal because it exceeds the peak tolerance value Vc. The results determined to be abnormal in this way are displayed on the display 23. FIG. 6 shows an example of a screen displayed by the display 23. In FIG. 6, the display screen 24 shows the date (DATE) and time (TIME) at which the abnormality was determined, and also shows a worm gear and a schematic diagram of the worm gear as the position where the abnormality has occurred. Therefore, since the inspection worker can identify abnormalities at a glance, the efficiency of inspection work can be greatly improved.

Next, in the diagnostic processor 19, the amplitude distribution of the input vibration signal is determined by the amplitude distribution calculator 25, and the peak amplitude value from this amplitude distribution is determined by the peak probe 26. A permissible vibration value is set in advance based on the model, size, or operation test of each electric valve, and this permissible vibration value is compared with the peak amplitude value determined by the peak probe 26 to determine if the permissible vibration value is exceeded. The priority determiner 27 determines the priority for inspection based on the magnitude of the difference between the amplitude value and the allowable value and displays it. Furthermore, the amplitude values and frequency analysis results obtained by the diagnostic processor 19 can be recorded and displayed as trend data. An example of a screen displayed by the display 23 is shown. In FIG. 7, the display screen 29 displays the date and time at the time of data recording and the vibration analysis results of the motor-operated valve.

[0017] According to the motor-operated valve diagnostic device constructed in this manner, an abnormality can be diagnosed by detecting the vibration of the motor-operated valve, analyzing the frequency of this vibration, and comparing it with a preset tolerance value. Furthermore, since the priority for inspection is determined based on the vibration amplitude value, the valve to be inspected can be selected, which greatly improves the efficiency of inspection work. Next, an electric valve diagnostic device according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 8 shows a block configuration diagram of an electric valve diagnostic device according to a second embodiment of the present invention. Note that the same parts in the figure as in FIG. 1 are indicated by the same reference numerals, and the explanation of the overlapping parts will be omitted.

In FIG. 8, each motor-operated valve 1 includes an acceleration sensor 14, an amplifier 15, an A/D converter 16, and a multiplex transmitter equipped with a transmission signal buffer for transmitting vibration signals. 17 and a receiver 18 are provided. Vibration signals are transmitted from the plurality of electric valves to the diagnostic processor 19 using a multiplex transmission method and are processed. In addition, signals from a large number of electric valves are transmitted from a multiplex transmitter 17 to a multiplex transmission cable 2.
8 and is transmitted to a diagnostic processor 19 via a receiver 18 having a time sharing function. The diagnostic processor 19 can simultaneously monitor multiple electric valves 1, record the vibrations of multiple electric valves 1 as trend data, calculate the amplitude value of each from this vibration, and determine the type and size of each electric valve. Priority is determined by comparing the size of the difference with a preset amplitude tolerance value, and the valve to be inspected is selected from a plurality of motor-operated valves.

Furthermore, since the receiver 18 sends vibration signal data to the diagnostic processor 19 using a time sharing method, the signal cable can be simplified by this multiplex transmission method.

[0020] With the above-described configuration, the second embodiment can also provide the same functions and effects as the first embodiment. Furthermore, in the second embodiment, a plurality of electrically operated valves can be monitored at the same time, and valves to be inspected can be selected more reliably, so that the efficiency of inspection work is greatly improved.

[0021]

As described above, according to the present invention, the motor-operated valve can be monitored by attaching a vibration detection means to the motor-operated valve and performing frequency analysis of the vibration obtained by the vibration detection means. Furthermore, abnormal areas can be identified. Furthermore, it is possible to prioritize the valves to be inspected based on the magnitude of the amplitude of the vibration, and this has the effect of improving the efficiency of inspection work.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram of an electric valve diagnostic device according to a first embodiment of the present invention.

FIG. 2 is a schematic structural diagram showing the driving principle of an electric valve.

FIG. 3 is a vibration waveform characteristic diagram showing vibrations of the motor-operated valve detected by the motor-operated valve diagnostic device according to the first embodiment of the present invention.

FIG. 4 is a characteristic diagram showing frequency components of an electric valve analyzed by the electric valve diagnostic device according to the first embodiment of the present invention.

FIG. 5 is a characteristic diagram showing frequency components of an electric valve analyzed by the electric valve diagnostic device according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an example of data display when an abnormality occurs in the electric valve diagnostic device according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram showing an example of displaying diagnostic results of a motor-operated valve in the motor-operated valve diagnostic device according to the first embodiment of the present invention.

FIG. 8 is a block diagram showing a transmission system of an electric valve diagnostic device according to a second embodiment of the present invention.

[Explanation of symbols]

1...Electric valve
2...Valve drive unit 3...Motor
4...Valve body 5...Valve box
6...
Valve part 7...motor pinion
8... Worm 9... Worm gear
10...Dry sleeve 11...Valve stem
12...Electric valve diagnostic device 13...Connection part
14... Acceleration sensor 15... Amplifier
16...A/D converter 17...multiplex transmitter
18...Receiver 19...Diagnostic processor
20...Frequency analyzer 21, 26...Peak probe 22...
Comparator 23...indicator
24, 29...Display screen 25...Amplitude distribution calculator 2
7...Priority determiner 28...Multiple transmission cable

Claims (2)

[Claims] Claim 1: A vibration detection means attached to an electric valve for detecting vibration, a frequency analysis means for analyzing the frequency of vibration detected by the vibration detection means to obtain a frequency component, and a frequency analysis means for determining a frequency component. A peak search means for calculating a peak value specific to the electric valve from the components, and a peak value obtained from the peak search means is compared with a predetermined peak tolerance value specific to the electric valve, and if the peak value exceeds the peak tolerance value. 1. A motor-operated valve diagnostic device comprising: a comparison judgment means for determining that there is an abnormality; and a display means for displaying a result judged by the comparison judgment means. 2. Vibration detection means for detecting vibration attached to an electric valve; amplitude distribution calculation means for calculating the amplitude distribution of the vibration detected by the vibration detection means; and an amplitude distribution calculated from the amplitude distribution calculated by the amplitude distribution calculation means. A peak exploration means for determining the peak amplitude value, and a difference between the peak amplitude value determined by the peak exploration means and an amplitude tolerance value, which is a predetermined tolerance value for the amplitude specific to the electric valve, is determined and inspected based on the magnitude of this difference. An electric valve diagnostic device comprising: priority determining means for determining the priority of a target; and display means for displaying the results obtained by the priority determining means.