Integral intelligent control valve for partial stroke test of PST

Abstract

The utility model discloses a PST part stroke test integral intelligent control valve, which comprises a control valve, a first cylinder, a second cylinder and a spring cylinder, the control valve is provided with a valve rod for controlling the opening degree of a valve port of the control valve, the first cylinder, the second cylinder and the spring cylinder jointly drive rotation acting on the valve rod, and the stroke of the second cylinder is far smaller than that of the first cylinder. The system further comprises a PST central controller, a first air source control mechanism and a second air source control mechanism, the PST central controller controls the second air source control mechanism to supply air to the second air cylinder or cut off air, and when the valve part stroke test is carried out, the PST central controller controls the second air source control mechanism to supply air to the second air cylinder. And the output force of the second cylinder and the output force of the spring cylinder overcome the output force of the first cylinder, so that the piston rod part of the first cylinder retreats, and the valve rod is driven to rotate to turn down the valve port of the control valve. Therefore, normal use of the control valve is ensured.

Description

Technical Field

[0001] The utility model relates to the field of valves, in particular to a PST partial stroke test integral intelligent control valve. Background Art

[0002] In desert areas, due to dryness, high temperature and heavy dust, the oil and gas pipeline valves used are generally shut-off valves. The shut-off valves are generally in the fully open position all year round, but the shut-off valves cannot be in the fully open state for a long time. They need to be inspected regularly to check whether the valve is stuck or failed. The inspection method is manual, but it is very time-consuming and laborious, and there may be missed inspections. The reliability of the inspection is poor, which makes it difficult to detect the shut-off valve that is not working properly. In an emergency, it is impossible to respond, which will pose a safety hazard. Utility Model Content

[0003] In order to solve the above problems, the purpose of the utility model is to provide a PST partial stroke test integral intelligent control valve with a stable and reliable structure, so as to ensure the normal use of the control valve.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a PST partial stroke test integral intelligent control valve, comprising a control valve, a first air cylinder, a second air cylinder and a spring cylinder, the control valve having a valve stem for controlling the opening of the control valve port, the first air cylinder, the second air cylinder and the spring cylinder jointly transmitting the rotation of the valve stem, the stroke of the second air cylinder is much smaller than that of the first air cylinder, the air supply output direction of the first air cylinder is opposite to that of the second air cylinder, and the air supply output direction of the first air cylinder is opposite to that of the reset direction of the spring cylinder, and also comprising a PST central controller, a first air cylinder, a second air cylinder and a spring cylinder. The PST central controller controls the second air source control mechanism to supply air to or cut off air to the second cylinder. When in working state, the first air source control mechanism keeps supplying air to the first cylinder, and the first cylinder overcomes the reset force of the spring cylinder to drive the control valve to keep in a normally open state. When the valve is partially stroke tested, the PST central controller controls the second air source control mechanism to supply air to the second cylinder, and the output force of the second cylinder and the output force of the spring cylinder overcome the output force of the first cylinder, so that the piston rod of the first cylinder partially retreats, and drives the valve stem to rotate to close the valve port of the control valve.

[0005] The upper end of the control valve is connected to a transmission box, one end of the valve stem extends into the transmission box, a spring cylinder is connected to one side of the transmission box, the output shaft of the spring cylinder penetrates into the transmission box and drives the valve stem to close the valve port of the control valve, the first cylinder and the second cylinder are arranged on the other side of the transmission box, one side of the first cylinder is connected to the transmission box, the other side of the first cylinder is connected in series with the second cylinder, the piston rod of the first cylinder, the piston rod of the second cylinder, the output shaft of the spring cylinder and the valve stem are linked and connected.

[0006] The piston rod of the first cylinder penetrates into the transmission case, a slider is connected between the output shaft of the spring cylinder and the piston rod of the first cylinder, a guide rail for guiding the slider to move is provided in the transmission case, and also includes a fork connected to the valve stem of the control valve, the slider is connected to a roller, the fork is provided with a limit shift groove, the roller is placed in the limit shift groove, the second cylinder is connected to the outer end of the first cylinder, the piston rod of the second cylinder penetrates into the first cylinder and contacts the piston rod in the first cylinder.

[0007] The first air source control mechanism includes a first air source, a first filter pressure reducing valve, a safety valve and a first solenoid valve. The first air source is connected to the first filter pressure reducing valve through a pipeline, the first filter pressure reducing valve is connected to the first solenoid valve through a pipeline, the first solenoid valve is connected to the safety valve through a pipeline, and the safety valve is connected to the air inlet of the first cylinder through a pipeline.

[0008] The second air source control mechanism includes a second air source, a second filter pressure reducing valve and a second solenoid valve. The second air source is connected to the second filter pressure reducing valve through a pipeline. The second filter pressure reducing valve is connected to the second solenoid valve through a pipeline. The second solenoid valve is connected to the air inlet of the second cylinder through a pipeline.

[0009] A stroke scale is also arranged on the transmission housing, and the stroke scale is drivingly connected to the piston rod of the first cylinder.

[0010] The output stroke of the second cylinder accounts for between 15% and 20% of the output stroke of the first cylinder.

[0011] The beneficial effects of the utility model are as follows: during a partial stroke test of the valve, the PST central controller controls the second air source control mechanism to supply air to the second cylinder, and the output force of the second cylinder and the output force of the spring cylinder overcome the output force of the first cylinder, so that the piston rod of the first cylinder partially retracts, and drives the valve stem to rotate to close the valve port of the control valve, while not affecting the circulation of the medium. During the test, whether the control valve is used normally can be detected by observing the digital changes on the stroke dial. The structure is stable and reliable, which improves the test efficiency and accuracy of the control valve and ensures the normal use of the control valve.

[0012] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an overall structural diagram of a specific implementation method of the utility model;

[0014] Figure 2 It is a state diagram of the PST partial stroke test in a specific implementation mode of the utility model;

[0015] Figure 3 This is a state diagram of the control valve being fully opened in a specific implementation mode of the utility model;

[0016] Figure 4 It is a structural diagram of the valve stem transmission structure in a specific implementation manner of the utility model. DETAILED DESCRIPTION

[0017] The present invention is specifically described below through embodiments, which are only used to further illustrate the present invention and should not be construed as limiting the protection scope of the present invention.

[0018] like Figure 1-Figure 4 As shown, this embodiment discloses a PST partial stroke test integral intelligent control valve, PST is the English abbreviation of partial stroke test, and the structure includes a control valve 1, the upper end of the control valve 1 is connected to a transmission housing 2, the valve stem of the control valve 1 is placed in the transmission housing 2, a spring cylinder 3 is connected to one side of the transmission housing 2, the output shaft of the spring cylinder 3 penetrates into the transmission housing 2 and drives the valve stem to open the valve port of the control valve 1, and a first cylinder 41 and a second cylinder 42 are connected to the other side of the transmission housing 2, the piston rod of the first cylinder 41 penetrates into the transmission housing 2 and is transmission-connected to the output shaft of the spring cylinder 3, and the second cylinder 42 Connected to the outer end of the first cylinder 41, the piston rod of the second cylinder 42 penetrates into the first cylinder 41 and contacts the piston rod in the first cylinder 41, the first cylinder 41 is connected with a first air source control mechanism 5 which can retract the piston rod of the first cylinder 41, a connecting seat 43 is provided between the first cylinder 41 and the second cylinder 42, two exhaust ports 44 are arranged on the connecting seat 43 for exhausting the first cylinder 41 and the second cylinder 42, the second cylinder 42 is connected with a second air source control mechanism 6 which can output the piston rod of the second cylinder 42, and a PST central controller is installed on the transmission box 2, The PST central controller controls the air supply or air cutoff of the second air source control mechanism 6 by setting parameters and programs. The air supply output direction of the first cylinder is opposite to that of the second cylinder, and the air supply output direction of the first cylinder is opposite to the reset direction of the spring cylinder. In the working state, the first air source control mechanism 5 keeps supplying air to the first cylinder 41, and the first cylinder 41 overcomes the reset force of the spring cylinder 3 to drive the control valve to remain in a normally open state. During the partial stroke test of the valve, the PST central controller controls the second air source control mechanism 6 to supply air to the second cylinder 42, and the output force of the second cylinder 42 overcomes the output force of the spring cylinder 3. The output force of the first cylinder 41 is used to make the piston rod of the first cylinder 41 partially retreat, and drive the valve stem to rotate and close the valve port of the control valve; the output stroke of the second cylinder 41 accounts for between 15% and 20% of the output stroke of the first cylinder 42, so that the piston rod of the first cylinder can return part of the stroke. This test can not only ensure that the control valve always maintains a normal normally open state and does not affect the transportation operation of the overall pipeline medium, but also avoid the control valve from getting stuck or verify whether the first and second cylinders fail, ensuring that the gas source can be cut off in an emergency when a fault occurs, and the spring cylinder reset drives the control valve to quickly cut off.

[0019] The first air source control mechanism 5 includes a first air source 51, a first filter pressure reducing valve 52, a safety valve 54 and a first solenoid valve 53. The first air source 51 is connected to the first filter pressure reducing valve 52 through a pipeline, the first filter pressure reducing valve 52 is connected to the first solenoid valve 53 through a pipeline, the first solenoid valve 53 is connected to the safety valve 54 through a pipeline, and the safety valve 54 is connected to the air inlet of the first cylinder 41 through a pipeline. When the first cylinder 41 drives the second cylinder 42, the air pressure of the first cylinder 41 will increase, so it is necessary to install a safety valve 54 to discharge the excess air source. In this way, the air pressure of the first air source 51 can be stably and cleanly input into the first cylinder 41, and the control valve can be kept in a normally open state after the first cylinder 41 is supplied with air.

[0020] The second air source control mechanism 6 includes a second air source 61, a second filter pressure reducing valve 62 and a second solenoid valve 63. The second air source 61 is connected to the second filter pressure reducing valve 62 through a pipeline, the second filter pressure reducing valve 62 is connected to the second solenoid valve 63 through a pipeline, and the second solenoid valve 63 is connected to the air inlet of the second cylinder 42 through a pipeline. In this way, it can be ensured that the air pressure of the second air source 61 is stably and cleanly input into the second cylinder 42, and when the valve partial stroke test is performed, the second cylinder 42 can output stably to drive the piston rod of the first cylinder to return to its original position.

[0021] The first gas source 51 and the second gas source 61 can be an outlet pipe on an air pump. The first solenoid valve 53 can control the on and off of the first cylinder, and the second solenoid valve 63 can control the on and off of the second cylinder.

[0022] A stroke dial 7 is also provided on the transmission housing 2, and the stroke dial 7 is drivingly connected to the piston rod of the first cylinder 41. In this way, the output stroke of the first cylinder 41 can be visually seen during manual inspection, so as to quickly know the opening state of the valve and detect whether the control valve is normal.

[0023] Among them, a slider 8 is connected between the output shaft of the spring cylinder 3 and the piston rod of the first cylinder 41, and a guide rail for guiding the slider 8 is provided in the transmission box 2, and also includes a fork 9 connected to the valve stem of the control valve. The slider 8 is connected by a roller 10, and the fork 9 is provided with a limit shift groove. The roller 10 is placed in the limit shift groove 91, so that the transmission connection with the valve stem is realized through the output shaft of the spring cylinder and the piston rod of the first cylinder. When the slider 8 moves, it drives the fork to rotate, and then drives the valve stem to rotate and drive the valve of the control valve to open or close, so that the first cylinder, the second cylinder and the spring cylinder jointly transmit the rotation of the valve stem.

[0024] By adopting the above technical solution, when the valve is partially stroke tested, the PST central controller controls the second air source control mechanism to supply air to the second cylinder. The output force of the second cylinder and the output force of the spring cylinder overcome the output force of the first cylinder, so that the piston rod of the first cylinder partially retreats and drives the valve stem to rotate and close the valve port of the control valve. At the same time, it will not affect the circulation of the medium. During the test, the control valve can be detected by observing the digital changes on the stroke dial to see whether it is used normally. The structure is stable and reliable, which improves the test efficiency and accuracy of the control valve, eliminates the safety hazards of the control valve, and ensures the normal use of the control valve.

[0025] It should also be noted that in this structure, the PST central controller mainly controls the switch of the first solenoid valve and the switch of the second solenoid valve, and then controls the action of the first cylinder and the second cylinder. The first cylinder, the second cylinder and the spring cylinder operate jointly. When there is no air supply, the spring cylinder is reset to put the control valve in a closed state. During partial stroke detection, only a little air needs to be supplied to the second cylinder to complete the detection. Even if the second cylinder fails, the stroke of the valve stem will only retreat a small part and will not affect the circulation of the medium. Once the entire pipeline system fails and the control valve needs to be closed, the control valve can be closed by cutting off the air source and driving the spring cylinder.

[0026] The PST partial stroke test system is a safety protection solution for emergency shut-off valves. Its principle is to make the valve (normally open control valve 1) perform periodic partial stroke action to ensure the normal use of the control valve 1. Therefore, the PST central controller is connected to the touch screen and can also add a timing test function. In industrial DCS control, the "PST partial stroke test function" is usually tested manually, and the manual test is performed once every one or two months. The "PST partial stroke test integral intelligent control valve" directly designs the timing function in the intelligent controller, and the "test" cycle can be set at will. This can avoid the valve stem rusting and jamming caused by the control valve not being turned on and off for a long time, ensure the normal operation of the control valve, and extend the service life of the control valve.

[0027] The PST partial stroke test integral intelligent control valve 1 does not use a "sensor" as the main body, and the actuator solves the instability of the sensor in harsh environments (high and low temperature changes and magnetic interference environments) with pure mechanical reliability.

[0028] By using the PST partial stroke test for the overall intelligent control valve 1, the online performance of the control valve 1 can also be analyzed by computer equipment, such as diaphragm head pressure, pressure difference, spring range and response time, etc.; through the software, the valve position-pressure change trend graph of the control valve 1 can be seen.

[0029] The above shows and describes the basic principles and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the utility model. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the utility model is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0030] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A PST partial stroke test integrated intelligent control valve, characterized in that: It includes a control valve, a first cylinder, a second cylinder and a spring cylinder. The control valve has a valve stem for controlling the opening of the control valve port. The first cylinder, the second cylinder and the spring cylinder jointly transmit and act on the rotation of the valve stem. The stroke of the second cylinder is much smaller than that of the first cylinder. The air supply output direction of the first cylinder is opposite to that of the second cylinder. The air supply output direction of the first cylinder is opposite to the reset direction of the spring cylinder. It also includes a PST central controller, a first air source control mechanism and a second air source control mechanism. The PST central controller controls the second air source control mechanism to supply air or cut off air to the second cylinder. In the working state, the first air source control mechanism keeps supplying air to the first cylinder. The first cylinder overcomes the reset force of the spring cylinder to drive the control valve to remain in a normally open state. When the valve is partially stroke tested, the PST central controller controls the second air source control mechanism to supply air to the second cylinder. The output force of the second cylinder and the output force of the spring cylinder overcome the output force of the first cylinder, so that the piston rod of the first cylinder partially retreats and drives the valve stem to rotate to close the valve port of the control valve.

2. The PST partial stroke test integrated intelligent control valve according to claim 1, characterized in that: The upper end of the control valve is connected to a transmission box, one end of the valve stem extends into the transmission box, a spring cylinder is connected to one side of the transmission box, the output shaft of the spring cylinder penetrates into the transmission box and drives the valve stem to close the valve port of the control valve, the first cylinder and the second cylinder are arranged on the other side of the transmission box, one side of the first cylinder is connected to the transmission box, the other side of the first cylinder is connected in series with the second cylinder, the piston rod of the first cylinder, the piston rod of the second cylinder, the output shaft of the spring cylinder and the valve stem are linked and connected.

3. The PST partial stroke test integrated intelligent control valve according to claim 2, characterized in that: The piston rod of the first cylinder penetrates into the transmission case, a slider is connected between the output shaft of the spring cylinder and the piston rod of the first cylinder, a guide rail for guiding the slider to move is provided in the transmission case, and also includes a fork connected to the valve stem of the control valve, the slider is connected to a roller, the fork is provided with a limit shift groove, the roller is placed in the limit shift groove, the second cylinder is connected to the outer end of the first cylinder, the piston rod of the second cylinder penetrates into the first cylinder and contacts the piston rod in the first cylinder.

4. The PST partial stroke test integrated intelligent control valve according to claim 1, characterized in that: The first air source control mechanism includes a first air source, a first filter pressure reducing valve, a safety valve and a first solenoid valve. The first air source is connected to the first filter pressure reducing valve through a pipeline, the first filter pressure reducing valve is connected to the first solenoid valve through a pipeline, the first solenoid valve is connected to the safety valve through a pipeline, and the safety valve is connected to the air inlet of the first cylinder through a pipeline.

5. The PST partial stroke test integrated intelligent control valve according to claim 1, characterized in that: The second air source control mechanism includes a second air source, a second filter pressure reducing valve and a second solenoid valve. The second air source is connected to the second filter pressure reducing valve through a pipeline. The second filter pressure reducing valve is connected to the second solenoid valve through a pipeline. The second solenoid valve is connected to the air inlet of the second cylinder through a pipeline.

6. The PST partial stroke test integrated intelligent control valve according to claim 2, characterized in that: A stroke scale is also arranged on the transmission housing, and the stroke scale is drivingly connected to the piston rod of the first cylinder.

7. The PST partial stroke test integrated intelligent control valve according to claim 1, characterized in that: The output stroke of the second cylinder accounts for between 15% and 20% of the output stroke of the first cylinder.

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