JP2001188606A - Shutoff valve testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To check the operation of a shutoff valve through on-line. SOLUTION: The shutoff valve testing device for testing each normally opened or normally closed shutoff valve arranged in a pipeline executes an operation test by sending a valve control signal of a degree not fully closing or fully opening the valve to the valve at the time of receiving a test command.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shut-off valve test apparatus for performing an operation test of a shut-off valve installed in a pipeline of a petroleum refinery plant, a chemical plant, etc., and more particularly, to an improvement so that an operation test can be performed online. Things.

[0002]

2. Description of the Related Art In petroleum refining plants, chemical plants, and the like, shut-off valves are installed in pipelines through which various liquids and gases flow for plant safety. Such shut-off valves are usually closed or open,
When an abnormality occurs in any of the plant facilities, the safety of the entire facility is ensured by opening the shut-off valve if it is closed or closing it if the shut-off valve is open.

On the other hand, shut-off valves are regularly inspected every few years,
The operation is confirmed by maintenance or the like. In this operation test, the entire facility had to be shut down for several weeks or about a month, and during this time, product production at this facility was also stopped, which was one of the hindrances to improving productivity.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to enable an operation test of a shut-off valve to be confirmed online.

[0005]

The present invention which has solved the above-mentioned problems is as follows: (1) In a shut-off valve test apparatus for testing a normally open or normally closed shut-off valve installed in a pipeline, A shut-off valve test apparatus for performing an operation test by sending a valve control signal to the shut-off valve to such an extent that the valve is not fully closed or fully opened upon receiving a test command. (2) The shut-off valve test device according to (1), wherein a result of the operation test is output to the outside. (3) The shut-off valve test device according to (1), further including a timer that starts when the valve control signal is sent to the shut-off valve. (4) The shut-off valve test apparatus according to (3), wherein the operation is abnormal when the shut-off valve does not reach the predetermined opening degree even when the timer expires. (5) The deterioration of the operation of the shut-off valve is predicted by monitoring a trend of the time measurement value of the timer (3).
The shut-off valve test device as described.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration block diagram of a shut-off valve control device of the present invention.

In FIG. 1, shutoff valves V, measuring instruments D1, D2, and D3 such as thermometers, pressure gauges, and flow meters are installed in pipelines P installed in various plants. Further, the measuring instruments D1, D2, D3 are connected to the safety instrumented system S,
When those measured values indicate an abnormality, the safety instrumented system S issues a shutdown command SD, and conventionally, the safety of the equipment has been achieved by opening the shutoff valve V → opening or closing → opening.

The present invention is characterized in that a test device T for performing an on-line test is installed in such a control device of the shut-off valve V. The test apparatus T sends the shut-down command SD from the safety instrumented system S to the shut-off valve V as it is, while receiving the test command test from the outside, opens the shut-off valve V in about 1 msec. / Issue a close command.

By the open / close command issued for about 1 msec, the shut-off valve V does not open or close completely, but opens or closes by a few% (ideally, about 10%). It is closed. Thereby, it is confirmed whether or not the shutoff valve V has normally reached the predetermined opening degree, and an operation test is executed.

Here, the opening / closing of the shut-off valve V by several percent is calculated in advance so that the opening does not adversely affect the operation condition of the entire equipment, and the opening / closing is made in advance. In order to achieve this, it is calculated in advance how long the opening / closing command is optimal.

The shutoff valve V has a limit switch LSO for detecting full opening of the valve body, a limit switch LSC for detecting full closing, and an opening or closing degree of several percent as described above. A predetermined opening limit switch LST to be detected is provided.

In practice, the shutoff valve V is opened and closed by air pressure AIR by opening and closing the solenoid valves EV1 and EV2.

Next, the operation of the apparatus of the present invention will be described with reference to FIG. A test command test is given to the test apparatus T online, that is, from an upper control computer system or a manual switch. Thereby, the test device T
Controls the shutoff valve V, which has been in the fully open state (LSO: H), in the closing direction. As a result, the shutoff valve V closes by a few percent (the position of the valve opening LST), and is again controlled to fully open. That is, when the test command test is received, the shutoff valve V is closed by only a few percent and is fully opened. In this way, the device according to the invention closes the valve by a small opening,
The operation status (normal / abnormal) of the shut-off valve V can be checked online.

Further, at the same time as receiving the test command test, the timer is started, and a set time TS (for example, about 10 m
If the opening of the shut-off valve does not reach the position of the limit switch LST and the time is up (the set time Ts of the timer is increased) even after elapse of about (sec), it is determined that the shut-off valve V is abnormal or the limit switch is faulty. I do. Its normal /
The abnormal operation result is transmitted to the outside as an alarm AL.

Although FIG. 2 shows a test for a normally open shutoff valve, the outline of the operation is the same for a normally fully closed shutoff valve.

FIG. 3 is a time chart of a logic sequence representing an operation when the above-described apparatus of the present invention is actually installed in a facility.

In this figure, the initial state is that the shutoff valve V is fully opened (the limit switch LSO is on). At time t1,
It is assumed that an abnormality has occurred in any of the equipment and a shutdown command SD has been received. As a result, the shutoff valve V is gradually closed, and the limit switch LST on the way is driven to be fully closed (the limit switch LSC is turned on). In this state, safety inspection and equipment inspection are performed.

After the safety inspection and the equipment inspection are completed, a reset (restart) is performed at time t2. As a result, the shutoff valve V gradually opens, drives the limit switch LST on the way, and is fully opened to start the normal operation similar to the initial operation again (the limit switch LSO is on).

Next, it is assumed that an online test command test is given at time t3. At this time, the timer is started at the same time. By this test command test, a very short closing command is given to the shutoff valve V, and the shutoff valve V
Goes in the direction of closing. If the shut-off valve V closes the desired number of% and drives the limit switch LST before the timer expires (value TS), the timer is reset,
The shut-off valve V is fully opened (the limit switch LSO is turned on), and normal operation is performed at time t4 (online test: normal).

Assume that an on-line test command test is given at time t5. At this time, as in the case of the time t3, the timer is also started, a close command is given to the shutoff valve V, and the shutoff valve V moves in the closing direction. However,
Even if the timer expires (time-up with the value TS), the timer expires if the shut-off valve V has not yet reached the desired several percent closed state and the limit switch LST is not driven. Due to the timer / time-up, the shutoff valve V has a device abnormality, a valve clogging, and the like, and it is determined that the shutoff valve V is abnormal.

In this way, the device of the present invention can perform an operation test of the shut-off valve online without stopping the normal operation of the facility.

Further, in the device of the present invention, the test command t
est until the shut-off valve V reaches the desired opening.
That is, the time until the limit switch LST is turned on and off is measured and recorded by a timer, so that, for example, if the timer measurement value gradually increases, the shut-off valve V may be in the direction of failure. I understand. In this manner, the trend of the timer value may be sequentially observed, and the failure alarm AL may be generated according to the trend situation.

The apparatus of the present invention may be installed in a central management center, or may be installed in an explosion-proof box or the like when installed in an explosion-proof area.

Further, in the embodiment shown in the figure, an example is described in which one shut-off valve is installed in one pipe and this shut-off valve is tested. However, a plurality of test devices are connected in series to a plurality of pipes. Alternatively, a configuration in which one device of the present invention is installed in a plurality of shutoff valves may be used.

[0025]

According to the present invention, the following effects can be obtained. According to the first aspect of the present invention, since the operation test is performed by sending a valve control signal to the shut-off valve to such an extent that the valve is not completely closed or fully opened, the operation test of the shut-off valve can be performed online during the normal operation of the equipment. .

According to the second aspect of the present invention, the result of the operation test can be output to the outside, so that the abnormality of the shut-off valve can be recognized even at a remote place such as a host computer system or an operation table.

According to the third aspect of the present invention, various applications of the test operation can be realized by starting the timer when the valve control signal is transmitted.

According to the fourth aspect of the present invention, the operation abnormality is determined when the shut-off valve does not reach the predetermined opening even if the timer expires, so that accurate abnormality recognition can always be realized.

According to the fifth aspect of the present invention, since the trend of the time measurement value of the timer is monitored to predict the deterioration of the operation of the shut-off valve, the self-diagnosis of the device can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a shut-off valve control device of the present invention.

FIG. 2 is a diagram showing the operation of the device of the present invention.

FIG. 3 is a diagram showing a time chart of a logic sequence of the device of the present invention.

[Explanation of symbols]

 P pipe V Shut-off valve S Safety instrumented system D1, D2, D3 Measuring instrument EV1, EV2 Solenoid valve T Test equipment LSO, LSC, LST Limit switch

Claims (5)

[Claims] In a shut-off valve test device for testing a normally open or normally closed shut-off valve installed in a pipeline, a valve control signal is transmitted to said shut-off valve to such an extent that the valve is not fully closed or fully opened in response to a test command. A shut-off valve test device that performs an operation test. 2. The shut-off valve test device according to claim 1, wherein a result of the operation test is output to the outside. 3. The shut-off valve test device according to claim 1, further comprising a timer that is started when the valve control signal is sent to the shut-off valve. 4. The shut-off valve test device according to claim 3, wherein an operation abnormality is caused when the shut-off valve does not reach a predetermined opening even if the timer expires. 5. The shut-off valve test device according to claim 3, wherein a trend of the time measurement value of the timer is monitored to predict the operation deterioration of the shut-off valve.