JP2003194671A - Function diagnostic method of valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To grasp an abnormal sign and to specify an abnormal spot during operation concerning various functions characteristic to a valve device without troubling a person at all, and to thereby perform specification of a repair part, limitation of the inspection range of a motor-operated valve and diagnosis of the abnormal sign. <P>SOLUTION: This valve device equipped with a motor-driven part for opening and closing the valve is provided with a torque sensor for detecting the torque characteristic from the valve fully-opened state to the valve fully-closed state, and a current sensor for detecting the current characteristic of the power supplied to the motor driven part. The valve is opened or closed at the diagnosis time, and output signals of both sensors are converted into digital signals, and the torque characteristic and the current characteristic at the diagnosis time are recorded. The various functions characteristic to the valve device are diagnosed based on the torque characteristic and the current characteristic recorded before the diagnosis time and the torque characteristic and the current characteristic recorded at the diagnosis time. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is capable of rationally diagnosing motor-operated valves (including solenoid valves) and other valve devices in a short time even during operation of a plant. The abnormality diagnosis of the valve device that enabled to switch from time management maintenance to condition monitoring maintenance, and the result of this diagnosis,
The present invention relates to prediction of deterioration of a valve device using a database consisting of a valve specification, a periodic inspection plan, and a maintenance history including a diagnosis, and further, creation of a maintenance plan.

[0002]

2. Description of the Related Art It has been a conventional practice to open a cover or the like of a motor-operated valve (including a solenoid valve) or other valve device, modify the valve device, attach a sensor, and diagnose an abnormality. ing.

However, in this way, the valve to be inspected is modified,
For safety reasons, it is necessary to turn off the power in order to temporarily install a sensor for diagnostic purposes, so the implementation period is limited to when the plant is stopped. The jig has to be installed in a site where the work space is small, and if the recovery work after the completion of diagnosis is taken into consideration, most of the work time is spent for the attachment / detachment work of the sensor.

Further, if all the sensors related to the valve to be inspected are permanently installed for diagnosis, all the sensors are required for each individual valve and the sensor cable is also permanently installed. It will have to be costly and administratively problematic.

As a device for diagnosing without modifying the valve device, for example, in a motor control center concentrated at a predetermined place in order to control the drive power source of a plurality of electric valves, the current of the power line and the control line is controlled. There is also a device which measures the voltage and the voltage, and diagnoses the motor-operated valve based on the power consumption of the motor.

[Problems to be Solved by the Invention]

When the electric power of the motor which is the drive source of the valve device is measured to detect the mechanical characteristics of the valve device when the valve is opened and closed, the motor that drives the valve is reliably operated even when the voltage drops by a required ratio. Since a large motor that can output an extra output at the rated voltage is used so that the valve can be opened and closed, power fluctuations are less likely to occur with respect to minute load fluctuations on the valve side. Therefore, it is difficult to monitor changes in the electric power of the motor and diagnose changes with time such as wear and backlash of the stem screw. Also, when monitoring and diagnosing the motor drive power, the magnitude of mechanical inertial force after the supply of voltage and current to the motor is stopped, and the torque held by the motorized valve after the motor is stopped causes fluid cutoff. In principle, it is impossible to determine whether or not this is sufficient.

Furthermore, since the conversion coefficient required when converting the electric power into the output torque of the drive section changes from moment to moment,
There is a problem that this cannot be accurately known and the accuracy is low.

On the other hand, it has a torque measuring function which is indispensable for diagnosing various functional parts of the valve device with high accuracy without opening and disassembling the cover at all, and can be operated even during plant operation. The device has not yet been developed so far.

The present invention uses a torque sensor that is permanently provided in the valve device and a temporary sensor that can be mounted with one touch, so that the valve device can be operated without any modification during plant operation or periodic inspection. By grasping the signs of abnormality in each functional part of the entire valve device and specifying the abnormal part, comprehensively and quantitatively specify the repaired part, limit the inspection range of the valve device, and predict the abnormality sign. Prediction of abnormalities and deterioration prediction of valve devices that can be performed without any skill, by making prediction judgments, predicting component replacement timings and determining maintenance timings by performing trend management from accumulated data. It is an object to provide a method and an apparatus.

[0010]

According to the present invention, the above problems can be solved as follows. (1) In a valve device equipped with an electric drive unit that opens and closes a valve, a torque sensor for detecting a torque characteristic from valve full opening to valve full closing, and a current characteristic of electric power supplied to the electric drive unit are detected. A current sensor is installed to open and close the valves at the time of diagnosis to convert the output signals of both sensors into digital signals and record the torque characteristics and current characteristics at the time of diagnosis, as well as the torque characteristics recorded before the diagnosis. Based on the current characteristics and the torque characteristics and current characteristics recorded during diagnosis,
Seat force, sliding resistance, torque switch misalignment and failure, torque margin of drive section under actual load, transmission system abnormality, valve sticking phenomenon, valve stem bending, valve stem breakage, position seat valve opening and closing time, and Change in valve stroke, amount of play due to wear of stem nut, amount of play due to loosening of locking nut, amount of play between valve stem and valve connecting part of sluice valve, operation position of instantaneous bypass limit switch, operation of full range bypass limit switch Diagnosing any of the location aptitudes.

(2) In the above item (1), the seat force is based on the torque characteristic and the current characteristic at the time of diagnosis. Diagnosis is made by comparing the value when the behavior of the device is stable and the torque characteristic is stable with the upper limit value and the lower limit value of the same value taken when the motor-operated valve is in a healthy state.

(3) In the above item (1), the sliding resistance is
Based on the torque characteristic and current characteristic at the time of diagnosis, the valve device determines the running torque value when the behavior of the valve device settles down in the intermediate operating state of the valve opening and closing operation and the torque is stable in both the opening operation and the closing operation. Diagnosis is made by comparing the upper limit value and the lower limit value of the same value collected in a healthy state.

(4) In the above item (1), the torque switch adjustment failure or failure is based on the torque characteristic and the current characteristic at the time of diagnosis after the electric drive unit is stopped in both the opening operation and the closing operation. A diagnosis is made by comparing the holding torque value when the behavior of the motor-operated valve is stable due to inertia and the like and the torque is stable with the upper limit value and the lower limit value of the same value taken when the valve device is in a healthy state.

(5) In the above item (1), the torque allowance of the drive unit under the actual load is based on the torque characteristic and the current characteristic at the time of diagnosis, and the electric drive unit is stopped in both the opening operation and the closing operation. Ratio of the holding torque value when the torque of the motorized valve stabilizes due to inertia, etc., and the running torque value when the behavior of the valve device stabilizes in the intermediate operating state of the valve opening / closing operation and the torque stabilizes. However, it is diagnosed by comparing with a reference value that is individually determined according to the valve specifications and the usage of the valve.

(6) In the above item (1), the abnormality of the transmission system is based on the torque characteristic and the current characteristic at the time of diagnosis, and the behavior of the valve device becomes stable in the intermediate operating state of the valve opening / closing operation, and the torque becomes stable. Diagnosis is made by detecting the disturbance of the running torque waveform.

(7) In the above item (1), when the valve sticking phenomenon is based on the torque characteristic and the current characteristic at the time of diagnosis, when the behavior of the valve device is stable and the torque is stable in the intermediate operating state of the valve opening / closing operation. Is diagnosed by comparing the running torque value of 1 with the same value taken when the valve device is in a healthy state.

(8) In the above item (1), the bending of the valve stem is based on the torque characteristic and the current characteristic at the time of diagnosis, and the behavior of the valve device becomes stable in the intermediate operating state of the valve opening / closing operation, and the torque becomes stable. The running torque waveform at the time is compared with the waveform obtained when the valve device is in a healthy state, and diagnosis is performed.

(9) In the above item (1), the valve rod breakage is
Based on the torque characteristics and current characteristics at the time of diagnosis, the running torque waveform when the behavior of the valve device settled down in the intermediate operating state of the valve opening and closing operation and the torque was stable, and when the valve device was in a healthy state were collected. Diagnosis is made by comparing the same waveforms.

(10) In the above item (1), the opening / closing time of the position seat valve and the valve stroke change are based on the torque characteristic and the current characteristic at the time of diagnosis, based on the hammer blow in the closing operation torque characteristic waveform at the time of diagnosis, Detects the amount of backlash generated in the locking nut part and stem nut by measuring the time until the running torque is generated and multiplying this by the moving speed of the valve stem, which was collected when the valve device was in a healthy state. To be diagnosed.

(11) In the above item (1), the amount of backlash due to the amount of wear of the stem nut is based on the torque characteristic and the current characteristic at the time of diagnosis, from the hammer blow at the time of closing operation until the running torque is generated. By measuring the time, and multiplying the measured time by the moving speed of the valve stem taken when the valve device is in a healthy state, the amount of backlash generated in the locking nut part and the stem nut is measured and diagnosed. Will be

(12) In the above item (1), the amount of looseness due to the loosening of the locking nut is based on the torque characteristic and the current characteristic at the time of diagnosis, from the hammer blow at the closing operation to the time when the running torque is generated. Measure time,
By multiplying the measured time by the moving speed of the valve rod taken when the valve device is in a sound state, the amount of backlash generated in the locking nut portion and the stem nut is measured for diagnosis.

(13) In the above item (1), the amount of backlash between the valve rod and the valve body coupling portion of the sluice valve is based on the torque characteristic and the current characteristic at the time of diagnosis, the electric drive unit is stopped, and When opening the valve in the closed state, measure the time from the end of absorbing the looseness of the locking nut and the wear of the stem nut to the valve withdrawal,
By multiplying the measured time by the moving speed of the valve stem taken when the valve device is in a healthy state, the amount of wear of the connecting portion of the valve stem and the valve body is measured to make a diagnosis.

(14) In the above item (1), when the operating position of the instantaneous bypass limit switch is based on the torque characteristic and the current characteristic at the time of diagnosis, when the valve element is pulled out from the fully closed state in the open direction operation, The torque value for pulling out the valve body is
When it is equal to or greater than the set torque value on the open side, and when that position is the proper operating position of the torque bypass limit switch, it is diagnosed by observing this with the waveform of the torque characteristic at the time of diagnosis.

(15) In the above item (1), the operating position of the full-range bypass limit switch measures the set torque value from the torque value when the motor current is cut off, based on the torque characteristic and the current characteristic at the time of diagnosis. It is diagnosed by detecting whether or not either the set torque or the holding torque collected when the valve device is in a healthy state is within a certain range.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments in which the present invention is applied to a motor-operated valve (including a solenoid valve) will be specifically described below with reference to the drawings. The present invention can also be applied to a fluid pressure type valve device and the like.

In FIG. 1, (1) is an electrically operated valve which is a valve to be inspected, (2) is an electrically driven device (driving section) for opening and closing the valve,
(3) is a power cable for supplying voltage and current to a motor (not shown) in the electric drive device (2).

A torque sensor (4) is permanently built in the electric drive unit (2) of the electric valve (1), and a vibration sensor (5) is temporarily attached. Power cable
A current sensor (energy sensor) (6) for detecting a supply current or a leakage current is temporarily attached to (3).

Instead of mounting the current sensor (6) on the power cable (3), a magnetic sensor may be mounted on the electric drive unit (2).

The sensors (4), (5) and (6) are connected to the data conversion unit (7), and the data conversion unit (7) is
The output signals of the sensors (4), (5) and (6) are converted and transmitted as diagnostic data to the arithmetic processing unit (8).

The arithmetic processing unit (8) receives the received data by A / D.
The function of displaying the diagnostic result at the measurement site by converting and immediately performing the analysis calculation process of the diagnostic data information and the diagnostic result and the diagnostic data are recorded in the storage means, and these diagnostic data and past diagnostic data are stored. It also has a function to comprehensively judge the abnormal parts of the drive part and the valve and the replacement time of the abnormal parts based on the regular inspection plan.

FIG. 2 shows an example of information obtained by the device of the present invention. The upper waveform is the torque signal waveform (A) by the output of the torque sensor (4), and the middle waveform is the current sensor.
The leakage current waveform (B) due to the output of (6), the lower waveform is
It is a mechanical vibration waveform (C) by the output of the vibration sensor (5), and each signal is opening-torque, opening-current, opening-machine according to the opening of the valve corresponding to the time axis of the horizontal axis. It has a characteristic waveform of vibration. 3 is an example of a block configuration of the device of the present invention, FIG. 4 is an example of a screen showing a normal or abnormal determination result, FIG. 5 is an example of deterioration prediction, and FIG. 6 is each torque signal waveform, that is, torque characteristics. Shows the relationship between and.

Next, by the sensors (4), (5) and (6),
The function of the motor-operated valve (1) and what kind of abnormality of the motor-driven drive device (2) will be described. The operating state of the motor-operated valve (1) can be easily known, mainly by determining the torque of its motor-driven drive unit, and the collected data can be obtained by the arithmetic processing unit from the operating characteristics of the motor-operated valve (1). It can be grasped by comparing with. That is, the motorized valve
Since the torque data when the operation of (1) is normal changes in synchronization with the valve operating force data, the operating state can be estimated as follows and can be a guideline for diagnosis.

(1) Recording of full-closed → fully-opened operation (during valve torque seat) As shown in the torque signal waveform (A1) of FIG. 6, before startup (holding torque on the closed side is working) → motor start (Torque relaxation in the closing direction) → Hammer blow → Absorption of play in the transmission system after the drive sleeve (torque is almost zero) → Absorption of play between the valve rod and valve body (slight increase in torque) → Pull out valve body (temporary increase in torque) → Intermediate valve operation (running torque is reduced and almost stable) → Torque is stopped by opening the valve (torque is large). Similarly, from the torque signal waveform (A1), it is sound if the proper holding torque required to shut off the fluid is maintained before starting. If the time until the end of absorbing the backlash after the hammer blow is not increased, it is determined that the transmission system is not worn or loosened. If the torque during the valve intermediate operation (running torque) does not increase or decrease compared to the normal state, it can be seen that there is no abnormality in the sliding portion. Furthermore, the torque when the power to the motor is cut off (set torque) and the torque after stopping (holding torque) are
If it is not increasing or decreasing with respect to the sound state, it is not deteriorated and it is judged that there is no abnormality in the sliding portion.

(2) Recording when fully opened → fully closed (at the time of sluice valve torque seat) As shown in the torque signal waveform (A2) of FIG. 6, before starting (holding torque works on the opening side) → motor start (Torque relaxation in the opening direction) → Hammer blow → Absorption of backlash in the transmission system after the drive sleeve (almost zero torque) → Intermediate valve operation (torque slightly increased and almost stable) → Torque stopped (torque increased) when the valve was fully closed. It is sound if the proper holding torque is maintained before starting. If the time until the end of absorbing the backlash after the hammer blow is not increased, it is determined that the transmission system is not worn or loosened. It can be seen that there is no abnormality in the sliding portion if the running torque during the valve intermediate operation does not increase or decrease compared to the normal state. Furthermore, if the torque when the power to the motor is cut off (set torque) and the torque after stopping (holding torque) have not increased or decreased compared to normal, it is judged that there is no abnormality in the sliding part. It

Hereinafter, the torque signal waveform (A1) shown in FIG.
The relationship between (A2), (A3) and (A4) and each diagnostic item, the diagnostic element and the evaluation method will be described.

[0036]

[Table 1]

(1) Seat force 1) Detecting element holding torque 2) Measuring method In either case of opening operation or closing operation, after the motor is stopped by torque stop, the behavior of the motorized valve due to inertia etc. settles down,
Measures the value when the torque is stable (in the case of automatic measurement, it is the final data of the collected torque sensor signal). 3) There is no standard for the judgment holding torque, but it is known from the experiment that the holding torque changes at a substantially same rate when the set torque changes at a certain rate, and therefore the judgment is made as follows. When the worm and worm wheel are self-tightening. The upper limit value and the lower limit value are predetermined based on the basic data collected when the motor-operated valve is in a healthy state, and when the measured value exceeds any of these, it is determined to be abnormal. The worm and worm wheel are not self-tightening (with motor brake). Upper limit value: A value determined from the basic data collected when the motor-operated valve is in a healthy state exceeds a certain limit, it is determined to be abnormal. Lower limit: If lower than the value calculated by motor brake braking torque x ratio x efficiency, it is determined to be abnormal.

(2) Sliding drag force 1) Detecting element running torque. 2) Measurement method In both open and closed operation, measure the value when the behavior of the motor-operated valve is stable and the torque is stable in the intermediate valve operating state. 3) There is no standard for judgment slide resistance, and the value set by the user is used as the judgment standard. Unless otherwise specified, use the following. In the case of no-load operation Based on the basic data collected when the motor-operated valve is in a healthy state, the upper and lower limits are set in advance, and if the measured value exceeds either of these, abnormal To determine. In the case of actual load operation, the upper and lower limits are set based on the initial actual pressure reduction data value after basic data collection when the motorized valve is in a healthy state, and the measured value exceeds either of these. If so, it is determined to be abnormal. However, perform the operation of fully closed and fully opened so that there is no fluid leakage from the gland packing. In addition, in both the no-load operation and the actual load operation, even if the judgment criterion is within the normal range, if a sharp change occurs in the trend management graph, the precise diagnosis is performed.

(3) Torque switch adjustment failure or failure. 1) Detection element setting torque. However, if the set torque is unclear, it is the holding torque. 2) Measuring method Measuring the set torque Measure the torque value when the motor current is cut off, which can be judged from the motor leakage current or the motor current. Holding torque measurement method In both opening and closing operations, after the motor is stopped by torque stop, the behavior of the motorized valve due to inertia etc. settles down,
Measure the value when the torque is stable. 3) Judgment Set torque standard (JEM1446) defines it within ± 10% of the design value. Therefore, if the set torque deviates from ± 10% of the value specified in the specification, it is determined to be abnormal. Holding torque Although there is no standard for holding torque, it is known from experiments that the holding torque changes at almost the same rate when the set torque changes at a certain rate, so the following determination is made. a) When the worm and worm wheel are self-tightening. Based on the value obtained from the basic data collected when the motorized valve is in a healthy state, the upper limit value and the lower limit value are set in advance,
If the measured value exceeds any of these, it is determined to be abnormal. b) When the worm and worm wheel are not self-tightening (with motor brake). Upper limit value: When the value exceeds the value obtained from the basic data collected when the motor-operated valve is in a healthy state,
Judge as abnormal. Lower limit value: If lower than the value calculated by motor brake braking torque x ratio x efficiency, it is determined to be abnormal.

(4) Torque allowance of drive section under actual load 1) Ratio of detected element setting torque and running torque. 2) Measurement method Holding torque ÷ Running torque Measurement of holding torque In both open and close operations, after the motor is stopped by torque stop, the behavior of the motorized valve due to inertia etc. settles down,
Measure the value when the torque is stable. Running torque measurement In both open and closed operation, the value is measured when the behavior of the motorized valve is stable and the torque is stable in the intermediate valve operating state. 3) Since there is no clear standard such as a judgment standard, if the ratio of the measured holding torque and running torque is below the standard value set individually according to the valve specifications and valve usage, it is judged as abnormal.

(5) Abnormality of transmission system 1) Detection element running torque and torque signal waveform. 2) Measuring method Visual inspection of the waveform 3) Abnormality of the judgment transmission system appears as periodic disturbance in the running torque waveform of the collected torque sensor signal, so the operator judges from the waveform and there is periodic disturbance. In that case, the failure point is specified from the cycle.

(6) Valve sticking phenomenon 1) Detection element running torque and torque signal waveform. 2) Measurement method In both open and closed operation, measure the value when the behavior of the motor-operated valve is stable and the torque is stable in the intermediate valve operating state. 3) When the judgment valve is stuck, when the torque of the motor is transmitted to the valve stem, a torque more than the set torque is immediately generated and the torque switch is activated to stop the torque. Therefore, it becomes abnormal in the determination of sliding resistance, and the collected waveforms are significantly different from those collected in the past, and
Since it is different from the waveform due to other problems, the operator can judge from the torque waveform.

(7) Bend of valve stem 1) Detection element running torque and torque signal waveform. 2) Measuring method In both open and closed operation, the value is measured when the behavior of the motor-operated valve is stable and the torque is stable in the valve intermediate operation state. 3) When the judgment valve rod is bent, the sliding resistance of the motor-operated valve increases when the curved portion of the valve rod and the interference part such as the gland packing come close to each other. Therefore, it becomes abnormal in the determination of sliding resistance, the collected waveform is significantly different from that collected in the past, and the running torque slowly rises, and when the bending part passes through the interference part, the running torque slows down. The operator can judge from the torque waveform.

(8) Valve rod breakage 1) Detection element running torque and torque signal waveform. 2) Measurement method In both open and close operations, measure the value when the behavior of the motor-operated valve is stable and the torque is stable in the valve intermediate operation state, and observe the torque signal waveform. 3) When the judgment valve rod is broken, when the rotational force of the motor is transmitted, the valve rod idles, and the sliding resistance becomes low.
Therefore, the determination of the sliding drag becomes abnormal, and the collected waveform is significantly different from that collected in the past, so that the operator can judge from the torque waveform.

(9) Position seat valve opening / closing time and valve stroke change 1) Detecting element operating time 2) Measuring method The time from hammer blow to valve stop is measured from the torque data waveform. 3) The judgment standard (JEM1446) allows a width of 15% for opening and closing times, so the measured data is the basic data.
If it is outside the range of +10 to -5% with respect to (the data when the electric valve is healthy), it is judged as abnormal.

(10) Amount of backlash due to amount of wear of stem nut 1) Absorption time of backlash of detection element. 2) Measuring method The time from the hammer blow at the time of closing operation until the running torque is generated is measured, and when the motorized valve is in a healthy state, the measured value of the valve stem previously measured as basic data is measured. By multiplying the moving speed, it is possible to detect the amount of backlash generated in the locking nut portion and the stem nut. 3) The amount of wear of the judgment stem nut is 30 of the stem nut thread width.
Since it is stipulated to be within%, if it exceeds this, it is judged as abnormal. Also, the loosening of the locking nut progresses rapidly, whereas the wear of the stem nut has the characteristic that it gradually progresses over a long period of time, so by accumulating data and performing trend management, both Can be distinguished.

(11) Amount of play due to loosening of locking nut 1) Absorption time of detection element play. 2) Measuring method The time from the hammer blow at the time of closing operation to the time when running torque is generated is measured, and when the motorized valve is in a healthy state, the measured value of the valve rod previously measured as basic data is measured. By multiplying the moving speed, the amount of backlash generated in the stem nut and the locking nut can be detected. 3) The detection element and the detection method for the looseness of the judgment locking nut are
Since it is exactly the same as the wear of the stem nut, the reference value is the same as the wear of the stem nut, and it is judged to be abnormal when backlash exceeding 30% of the width of the stem nut thread is detected. Wear of the stem nut gradually progresses over a long period of time, while loosening of the locking nut has a characteristic that it rapidly progresses. can do.

(12) Amount of backlash between valve rod and valve disc coupling portion of the gate valve 1) Absorption time of backlash of detection element. 2) Measuring method Measure the time from the end of absorbing the looseness of the locking nut and the wear of the stem nut to the valve withdrawal when opening the valve in the fully closed state by stopping the torque. By multiplying this by the moving speed of the valve stem, which is measured in advance as basic data, it is possible to detect the amount of wear of the connecting portion of the valve stem and the valve body. 3) There is no general rule regarding the amount of wear of the valve stem-valve joint in the judgment gate valve, so an abnormality is detected by comparison with the manufacturer default value or the user default value entered in the database in advance. judge.

(13) Operating position of the instantaneous bypass limit switch 1) Torque signal waveform at the time of starting the detecting element. 2) Judgment In the case of a closed-side torque seat sluice valve, from the fully closed state, when a force more than the open-side set torque is required when pulling out the valve element in the opening direction operation, if the torque bypass limit switch operating position is appropriate. Make sure that the valve element pulls out and operates normally. However, when operating in the opening direction with the operating position of the torque bypass limit switch deviating toward the fully closed side, before the valve is pulled out,
Since it stops due to the force of the open side set torque, if this is observed in the torque signal, it is determined to be abnormal. In the case of a closed-side torque seat sphere valve, when a force greater than the open-side set torque is generated due to the hammer blow effect in the operation in the opening direction, the valve operates properly at the proper torque bypass limit switch operating position. However, if the operation position of the torque bypass limit switch is shifted to the fully closed side and the opening direction operation is performed, the torque bypass limit switch stops at the hammer blow position at the opening side set torque. If the signal is observed, it is judged to be abnormal.

(14) Operating position of full range bypass limit switch 1) If the operating position of the detection element torque bypass limit switch is appropriate, close to full open during open operation and close to full close during closed operation. Torque bypass limit switch contact is OF
After that, the valve is stopped by the torque switch (set torque). However, if the operating position of the torque bypass limit switch deviates from the operating position of the torque switch to the fully open side during the open operation and to the fully closed side during the close operation, the torque bypass limit switch contact is turned on. During the period, the motor does not stop even if the torque switch operates, and continues to operate until the bypass is released within the amount of power that the motor can output. As a result, the set torque apparently increases and the holding torque also increases. Therefore, the detection element has the set torque or the holding torque. 2) Measuring method Measuring the set torque Measure the torque value when the motor current is cut off, which can be judged from the motor leakage current or the motor current. Holding torque measurement method In both opening and closing operations, after the motor is stopped by torque stop, the behavior of the motorized valve due to inertia etc. settles down,
Measure the value when the torque is stable. 3) Judgment The set torque standard (JEM1446) defines that it is within ± 10% of the design value. Therefore, if the set torque deviates from ± 10% of the value specified in the specification, it is determined to be abnormal. Holding torque Although there is no standard for holding torque, it is known by experiments that the holding torque also changes at a similar rate when the set torque changes at a certain rate, so the following determination is made. a) When the worm and worm wheel are self-tightening. An upper limit value and a lower limit value are set based on the value obtained from the basic data collected when the motor-operated valve is in a healthy state, and when either of these values is exceeded, it is determined to be abnormal. b) When the worm and worm wheel are not self-tightening (with motor brake). Upper limit value: If the value exceeds a certain range of values obtained from the basic data collected when the motor-operated valve is in a sound state, it is determined to be abnormal. Lower limit value: If lower than the value calculated by motor brake braking torque x ratio x efficiency, it is determined to be abnormal.

If the above-mentioned diagnosis determines that there is an abnormality, necessary measures such as issuing a warning or an alarm will be taken.

Deterioration Prediction and Maintenance Plan Creation When a certain motorized valve has diagnostic data accumulated a plurality of times as shown in FIG. 5, the tendency of change is extracted from the diagnostic data information for each diagnostic item. Then, the time to reach the reference value for determining the soundness of the motor-operated valve is obtained. In addition, if the schedule for regular inspection is set in the database, it will be listed as one of the valves subject to maintenance at the time of regular inspection immediately before the time when the deterioration of the valve to be inspected reaches the reference value, and the maintenance contents will be listed. Is added to the database and displayed.

[0053]

According to the present invention, a compact and lightweight portable abnormality diagnosis and deterioration prediction device including a data exchange unit and an arithmetic processing unit is permanently built in to output a torque signal specific to a valve device. By using a torque sensor, a temporary energy sensor that detects a current including a leakage current that can be mounted with one touch, and a temporary vibration sensor that detects vibration, various valve functions can be accurately diagnosed. At the same time, it is not necessary to open the cover etc. at the time of diagnosis, and it is possible to perform diagnosis in a short time without touching the valve device, and it is performed not only while the plant is stopped but also during operation. You can do it, and 1
A single device can manage multiple valve devices.

Further, one unit having a database function by having a diagnostic function and a database function (data, valve specifications, allowable values for each diagnostic item, diagnostic data, etc.) possessed by the arithmetic processing unit in separate arithmetic processing units. An arithmetic processing unit of
It is also possible to prepare a plurality of arithmetic processing devices having a diagnostic function and construct a configuration for exchanging necessary data by mutual communication.

In addition, it is possible to predict the deterioration of each sliding part and other movable parts, and eventually the usage limit or the replacement time.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an embodiment of a device of the present invention.

FIG. 2 is a diagram showing an example of information obtained by the device of the present invention.

FIG. 3 is a diagram showing an example of a block configuration of an apparatus of the present invention.

FIG. 4 is a diagram showing an example of a screen showing a normal or abnormal determination result.

FIG. 5 is a diagram illustrating an example of deterioration prediction.

FIG. 6 is a diagram showing a relationship between a waveform and a diagnostic element.

[Explanation of symbols]

(1) Motorized valve (2) Electric drive (3) Power cable (4) Torque sensor (5) Vibration sensor (6) Current sensor (7) Data conversion unit (8) (9) Processor

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Susumu Watanabe             7 Kirihara Town, Fujisawa City, Kanagawa Prefecture             Inside Chigi Engineering (72) Inventor Tomoaki Tsunoda             7 Kirihara Town, Fujisawa City, Kanagawa Prefecture             Inside Chigi Engineering F term (reference) 2G024 AA18 AD25 BA11 CA12 CA13                       CA18 FA06                 3H066 AA03 BA38

Claims (15)

[Claims] 1. A valve device having an electric drive section for opening and closing a valve, a torque sensor for detecting a torque characteristic from full valve opening to full valve closing, and a current characteristic of electric power supplied to the electric drive section. Is equipped with a current sensor to detect the, and the valve is opened and closed at the time of diagnosis to convert the output signals of both sensors into digital signals.
The torque characteristic and current characteristic at the time of diagnosis are recorded, and based on the torque characteristic and current characteristic recorded before the diagnosis and the torque characteristic and current characteristic recorded at the time of diagnosis, seat force, sliding resistance, torque Poor adjustment or failure of switch, torque margin of drive section under actual load, transmission system abnormality, valve sticking phenomenon, valve stem bending, valve stem breakage, position seat valve opening / closing time and valve stroke change, stem nut wear amount The amount of backlash due to, the amount of backlash due to loosening of the locking nut, the amount of backlash between the valve stem and valve connecting part of the sluice valve, the operating position of the instantaneous bypass limit switch,
A method for diagnosing the function of a valve device, which comprises diagnosing any of the suitability of an operating position of a global bypass limit switch. 2. The seating force is based on the torque characteristic and the current characteristic at the time of diagnosis, and after the electric drive unit is stopped in the opening operation and the closing operation of the valve, the behavior of the valve device due to inertia and the like is settled down, and the torque characteristic is set. The method for diagnosing the function of the valve device according to claim 1, wherein the value when the motor valve is stable is compared with the upper limit value and the lower limit value of the same value taken when the motor-operated valve is in a healthy state. 3. The sliding force is based on the torque characteristic and the current characteristic at the time of diagnosis, and the behavior of the valve device is stable in the intermediate operating state of the valve opening / closing operation in both the opening operation and the closing operation, and the torque is stable. The method for diagnosing the function of a valve device according to claim 1, wherein the running torque value at time is compared with an upper limit value and a lower limit value of the same value that are collected when the valve device is in a healthy state. 4. The torque switch adjustment failure and failure
Based on the torque characteristics and current characteristics at the time of diagnosis, in both the opening operation and the closing operation, after the electric drive unit stops, the behavior of the electric valve settles down due to inertia etc., and the holding torque value when the torque is stable, The method for diagnosing the function of a valve device according to claim 1, wherein the valve device is diagnosed by comparing with an upper limit value and a lower limit value of the same value that are collected when the valve device is in a healthy state. 5. The torque margin of the drive unit under the actual load is based on the torque characteristic and the current characteristic at the time of diagnosis, and the opening operation,
In any of the closing operations, after the electric drive unit stops, the behavior of the electric valve settles due to inertia, etc., the holding torque value when the torque is stable, and the behavior of the valve device settles in the intermediate operating state of the valve opening / closing operation, The function diagnostic method for the valve device according to claim 1, wherein the ratio of the running torque values when the torque is stable is compared with a reference value that is individually determined according to valve specifications and valve usage conditions. 6. The abnormality of the transmission system is based on the torque characteristic and the current characteristic at the time of diagnosis, and the behavior of the valve device is stabilized in the intermediate operating state of the valve opening / closing operation, and the disturbance of the running torque waveform when the torque is stable is suppressed. Claim 1 which detects and is diagnosed
A method for diagnosing the function of the valve device according to. 7. The running torque value when the behavior of the valve device is stable and the torque is stable in the intermediate operating state of the valve opening / closing operation based on the torque characteristic and the current characteristic at the time of diagnosis of the valve sticking phenomenon, The method for diagnosing the function of the valve device according to claim 1, wherein the diagnosis is performed by comparing the same with the same value collected when the valve is in a healthy state. 8. A running torque waveform when the bending of the valve stem is based on the torque characteristic and the current characteristic at the time of diagnosis, the behavior of the valve device is stable in the intermediate operating state of the valve opening / closing operation, and the torque is stable, and The function diagnostic method for the valve device according to claim 1, wherein the function is diagnosed by comparing the same waveforms collected when the device is in a healthy state. 9. The running torque waveform when the valve stem behavior is stable and the torque is stable in the intermediate operating state of the valve opening and closing operation based on the torque characteristic and the current characteristic at the time of diagnosis, and the valve apparatus. The method for diagnosing the function of the valve device according to claim 1, wherein the diagnosis is performed by comparing the same waveforms collected when the is in a healthy state. 10. The time from the hammer blow to the generation of running torque in the closing operation torque characteristic waveform at the time of diagnosis, based on the torque characteristic and the current characteristic at the time of diagnosis, based on the torque characteristic and the current characteristic at the time of diagnosis of the position seat valve. Is measured and multiplied by the moving speed of the valve stem, which is collected when the valve device is in a healthy state, and the amount of backlash generated in the locking nut portion and the stem nut is detected to make a diagnosis. The function diagnostic method for the valve device according to claim 1. 11. The amount of backlash due to the amount of wear of the stem nut is measured based on the torque characteristic and the current characteristic at the time of diagnosis by measuring the time from the hammer blow at the closing operation until the running torque is generated. The amount of backlash generated in the locking nut portion and the stem nut is measured by multiplying the moving speed of the valve rod taken when the valve device is in a healthy state at a certain time, and diagnosis is performed.
A method for diagnosing the function of the valve device according to. 12. The amount of backlash due to loosening of the locking nut is measured based on the torque characteristic and current characteristic at the time of diagnosis, and the time from the hammer blow at the closing operation until the running torque is generated is measured. The diagnosis is made by measuring the amount of backlash generated in the locking nut portion and the stem nut by multiplying the moving speed of the valve rod collected when the valve device is in a healthy state at a certain time. Method for diagnosing the valve device of. 13. The amount of backlash between the valve rod and the valve disc connecting portion of the sluice valve is based on torque characteristic and current characteristic at the time of diagnosis, the electric drive unit is stopped, and the valve in the fully closed state is opened. When the valve nut is in a healthy state by measuring the time from the end of absorbing looseness due to the loosening of the locking nut and the wear of the stem nut to the time of valve withdrawal when 2. The method for diagnosing the function of a valve device according to claim 1, wherein the function of the valve device is diagnosed by multiplying the moving speed of the valve rod sampled in (1) to measure the amount of wear of the connecting portion of the valve rod and the valve body. 14. The torque for pulling out the valve body when the valve body is pulled out in the opening direction operation from the fully closed state based on the torque characteristic and the current characteristic at the time of diagnosis of the operating position of the instantaneous bypass limit switch. When the value is equal to or greater than the set torque value on the open side, or when the position is the proper operating position of the torque bypass limit switch, it is observed by the waveform of the torque characteristic at the time of diagnosis and diagnosis is performed. Item 1. A method for diagnosing the function of a valve device according to Item 1. 15. The operating position of the all-pass bypass limit switch measures the set torque value from the torque value when the motor current is cut off based on the torque characteristic and the current characteristic at the time of diagnosis, and the set torque and the valve device are The method for diagnosing the function of a valve device according to claim 1, wherein it is diagnosed by detecting whether or not any one of the holding torques collected in a healthy state is within a certain range.