Method and device for testing motion state of valve rod of control valve

Abstract

The invention relates to the field of control valve testing, in particular to a method and device for testing the motion state of a valve rod of a control valve. According to the method for testing the motion state of the valve rod of the control valve, the valve rod is tested through a testing valve equivalent to a corresponding control valve, the testing valve comprises a valve body, the valve rod and a valve sleeve, one end of the valve rod is connected with the testing rod, and the testing rod penetrates out of the valve body and is in sliding sealing fit with the valve body; a control cavity is defined by the testing rod, the valve body and the corresponding end of the valve rod, and a monitoring device is arranged at the position, corresponding to the testing rod, outside the valve body to monitor the motion state of the testing rod so as to obtain the motion state of the valve rod. The method and device for testing the motion state of the valve rod of the control valve are low in testing cost, the mechanical motion of the valve rod can be monitored in real time, and the testing result is more visual.

Description

Technical Field

[0001] The invention relates to the field of control valve testing, and in particular to a control valve stem motion state testing method and device. Background Art

[0002] Hydraulic operating mechanisms are widely used in power grids with voltage levels of 252kV and above. The action characteristics of the control valve in the hydraulic operating mechanism will directly affect the opening and closing characteristics of the circuit breaker. At the same time, with the development of technologies such as phase selection and closing, the requirements for the stability of the hydraulic operating mechanism are becoming higher and higher, which requires the valve stem of the control valve to have higher motion stability. Therefore, it is necessary to test the motion state of the valve stem of the control valve.

[0003] At present, the control valves in the hydraulic operating mechanism mostly adopt a two-position three-way sliding valve structure. When performing opening and closing operations, the valve stem reciprocates in the valve sleeve, and the entire valve stem is wrapped by the valve sleeve and the valve body. The movement state of the valve stem cannot be directly monitored. The commonly used test method is to install the control valve on the hydraulic operating mechanism and conduct a whole machine test in conjunction with the circuit breaker. However, this test method can only obtain a composite result of multiple factors, and cannot deeply and finely analyze the movement of the valve stem, nor can it intuitively reflect the stability of the switching state of the control valve. At the same time, there is also the problem of high testing costs. Summary of the invention

[0004] The purpose of the present invention is to provide a method for testing the movement state of a control valve stem, so as to solve the problem that the existing testing method cannot intuitively reflect the movement state of the control valve stem and the testing cost is high; the purpose of the present invention is also to provide a device for testing the movement state of a control valve stem, so as to solve the problem that the existing testing method cannot intuitively reflect the movement state of the control valve stem and the testing cost is high.

[0005] To achieve the above purpose, the control valve stem motion state testing method of the present invention adopts the following technical solutions: A method for testing the movement state of a control valve stem, the method is to test through a test valve equivalent to the corresponding control valve, the test valve comprising a valve body, a valve stem and a valve sleeve, a test rod is connected to one end of the valve stem, the test rod passes through the outside of the valve body and cooperates with the valve body in a sliding seal, there is a gap between the test rod and the valve body, and a monitoring device is provided at a position outside the valve body corresponding to the test rod to monitor the movement state of the test rod and thereby obtain the movement state of the valve stem.

[0006] Furthermore, a sliding sealing ring is provided between the test rod and the valve sleeve for slidingly sealing between the test rod and the valve sleeve.

[0007] Further, the diameter of the test rod is not greater than one fifth of the diameter of the valve stem.

[0008] Furthermore, the valve body is provided with a low-pressure chamber for communicating with the oil tank and a high-pressure chamber for communicating with the accumulator.

[0009] Furthermore, a gate-opening pilot valve and a gate-closing pilot valve are provided on the valve body.

[0010] Beneficial effects: The control valve stem motion state testing method of the present invention is a pioneering invention. The control valve stem motion state testing method of the present invention is to test through a test valve equivalent to the corresponding control valve, a test rod that moves synchronously with the valve stem is provided at one end of the valve stem, the test rod extends out of the valve body, a monitoring device is provided outside the valve body, and the movement of the test rod can be monitored in real time by the monitoring device to obtain the motion state of the control valve stem, thereby realizing real-time monitoring of the mechanical movement of the valve stem, and the test results are more intuitive. The control valve stem motion state testing method of the present invention has low testing cost, can realize real-time monitoring of the mechanical movement of the valve stem, and the test results are more intuitive.

[0011] The control valve stem motion state testing device of the present invention adopts the following technical solutions: A control valve stem movement state testing device, which is a test valve equivalent to the corresponding control valve, includes a valve body, a valve stem and a valve sleeve, a test rod is connected to one end of the valve stem, the test rod passes through the valve body and cooperates with the valve body in a sliding seal, there is a gap between the test rod and the valve body, and a monitoring device is provided at a position outside the valve body corresponding to the test rod to monitor the movement state of the test rod.

[0012] Furthermore, a sliding sealing ring is provided between the test rod and the valve sleeve for slidingly sealing between the test rod and the valve sleeve.

[0013] Further, the diameter of the test rod is not greater than one fifth of the diameter of the valve stem.

[0014] Furthermore, the valve body is provided with a low-pressure chamber for communicating with the oil tank and a high-pressure chamber for communicating with the accumulator.

[0015] Furthermore, a gate-opening pilot valve and a gate-closing pilot valve are provided on the valve body.

[0016] Beneficial effects: The control valve stem motion state test device of the present invention is an improved invention. The control valve stem motion state test device of the present invention is a test valve equivalent to the corresponding control valve, including a valve body, a valve stem and a valve sleeve. A test rod that moves synchronously with the valve stem is provided at one end of the valve stem. The test rod extends out of the valve body. A monitoring device is provided outside the valve body. The motion state of the control valve stem can be obtained by real-time monitoring of the movement of the test rod using the monitoring device, and real-time monitoring of the mechanical movement of the valve stem can be achieved, and the test results are more intuitive. The control valve stem motion state test device of the present invention has low testing cost, can achieve real-time monitoring of the mechanical movement of the valve stem, and the test results are more intuitive. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of an embodiment of a control valve stem motion state testing device of the present invention; Figure 2 It is a schematic diagram of the compensation strategy based on valve stem switching data of the control valve stem motion state testing method of the present invention.

[0018] In the figure: 1. valve body; 2. left valve sleeve; 3. valve stem; 4. right valve sleeve; 5. first sliding sealing ring; 6. second sliding sealing ring; 7. opening pilot valve; 8. closing pilot valve; 9. sliding sealing ring of test rod; 10. test rod. DETAILED DESCRIPTION

[0019] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0020] The present invention proposes a control valve stem movement state testing method and device in response to the problems that the existing testing method requires the control valve to be installed on a mechanism and cooperated with a circuit breaker to perform a whole machine test, the test results are not intuitive, and the testing cost is high. The control valve stem movement state testing method of the present invention is to test the valve stem through a test valve equivalent to the corresponding control valve, a test rod that moves synchronously with the valve stem is provided at one end of the valve stem, the test rod extends out of the valve body, and a monitoring device is used to monitor the movement of the test rod to obtain the movement state of the valve stem, thereby realizing real-time monitoring of the mechanical movement of the valve stem.

[0021] The specific implementation method of the control valve stem motion state testing method of the present invention is as follows: In a basic embodiment, Figure 1 As shown, the method is to test the valve stem through a test valve equivalent to the corresponding control valve, and a test rod 10 is set at the right end of the valve stem 3. One end of the test rod 10 is fixedly connected to the valve stem 3 and moves synchronously with the valve stem 3, and the other end extends out of the valve body 1. The test rod 10, the valve body 1 and the corresponding ends of the valve stem 3 form a control cavity to ensure that the valve stem can move normally, and a monitoring device is set at the position corresponding to the test rod 10 outside the valve body 1 to monitor the movement of the test rod 10, thereby obtaining the movement state of the valve stem 3.

[0022] In other embodiments, the test rod 10 and the valve stem 3 can be processed into an integral structure or connected together by means of threads or the like, and move synchronously with the valve stem 3 .

[0023] In other embodiments, the monitoring device may be a laser sensor or a linear sensor, or may use a high-speed camera or other device to monitor the movement of the test rod 10 in real time.

[0024] In a preferred embodiment, a test rod sliding seal ring 9 is added to the right valve sleeve 4 to ensure the sliding seal between the test rod 10 and the right valve sleeve 4 .

[0025] In other embodiments, other sliding seals may be used between the test rod 10 and the right valve sleeve 4 to ensure sliding sealing between the test rod 10 and the right valve sleeve 4 .

[0026] In a preferred embodiment, the diameter of the test rod 10 is no more than one fifth of the diameter of the valve stem. The test rod 10 has little effect on the self-retaining area ratio of the valve stem 3 and basically does not affect the movement force and position retention ability of the valve stem 3, thereby ensuring that the test results are more accurate.

[0027] In a preferred embodiment, the control chamber Z connected to the rodless chamber of the hydraulic cylinder in the valve body 1 is eliminated, and only the low-pressure chamber T connected to the system oil tank and the high-pressure chamber P connected to the accumulator are retained. The control valve does not discharge oil to the outside, so that the valve stem is not affected by external forces, and the test result is more accurate.

[0028] In other embodiments, the control chamber Z communicating with the rodless chamber of the hydraulic cylinder may also be retained in the valve body 1 , without affecting the overall test result of the valve stem 3 .

[0029] In a preferred embodiment, an opening pilot valve 7 and a closing pilot valve 8 are installed on the valve body 1 to control the opening and closing operations of the control valve.

[0030] Through repeated tests, the switching stability of the valve can be obtained to guide production and improve the structure of the control valve. In products with strict requirements on the switching time of the control valve, such as phase selection, batch monitoring of the valve stem switching time can be used to screen out unqualified products. At the same time, data screening and statistics of the valve stem switching time can be performed during the workshop assembly process, which can be used as a subsequent phase selection compensation measure. The compensation ideas are as follows: Figure 2 As shown, the prototype is operated and the valve stem switching time is counted to find out the discrete distribution law of the valve stem switching time; the test valve is installed in the operating mechanism to count the action time of the circuit breaker as a whole to find out the discrete distribution law of the circuit breaker action time, and the discrete distribution laws of the two are matched and learned to give a compensation strategy based on the valve stem switching data; when producing products, the valve stem switching time can be counted in advance during the workshop assembly process, the structure of the test valve can be replaced with the factory structure, the test rod sliding seal ring 9 and the test rod 10 can be cancelled, and a circuit breaker with high stability can be obtained by combining the compensation strategy based on the valve stem switching data and the factory structure.

[0031] The compensation strategy based on valve stem switching data is to provide a time correction. In some specific scenarios of the power grid, certain specific operations of the power grid system need to be deeply associated with the action time of the mechanism, and specific operations need to be started before the mechanism action is completed or even before the action begins, which requires the action time of the mechanism to be predicted. The usual practice is to preset the action time of a mechanism, and operation X is performed based on this preset time. The time for operation X cannot deviate greatly from the actual action time of the mechanism, otherwise it will cause damage to the system. This requires the mechanism to have a high action stability, and usually requires this time deviation to be within 1ms.

[0032] The specific steps for time correction are as follows: Assuming that under ideal conditions, the (standard or neutral) closing time of a circuit breaker is t1, and the fluctuation meets the requirements, the valve stem switching time is t2, and the time when the instruction for operation X is issued is tx; assuming that under certain working conditions, the closing time of the circuit breaker is t3, t3-t1=t5>1 (taking the time lengthening as an example), the valve stem switching time is t4, t4-t2=t6 (note that t1 to t6 can be understood as personalized parameters of each product, which are different from each other), and the difference between t3 and tx will exceed the standard.

[0033] According to the previous tests and batch learning, the relationship between t6 and t5 can be obtained, that is, t5=f(t6). If the t4 and t6 of the control valve under the working condition can be tested in advance, the compensation value Δt=f(t6) can be given according to the learned function. The compensation device will correct the standard action time tx1 based on the circuit breaker to tx2=tx1+Δt and provide it to the system (that is, delay the issuance of the X action instruction). At this time, the difference between tx2 and t3 can fall within the normal range, thereby correcting the action time. Similarly, if the number of samples is sufficient and the subsequent algorithm is mature, the fluctuation data of the valve can be collected and implanted into the system, and a similar noise reduction method can be used to compensate in real time to improve the nominal stability of the whole machine.

[0034] The specific embodiment of the control valve stem motion state testing device of the present invention is as follows: In a basic embodiment, Figure 1 As shown, the control valve stem movement state test device of the present invention is a test valve equivalent to the corresponding control valve, and a test rod 10 is provided at the right end of the valve stem 3. One end of the test rod 10 is fixedly connected to the valve stem 3 and moves synchronously with the valve stem 3, and the other end extends out of the valve body 1. The test rod 10, the valve body 1 and the corresponding ends of the valve stem 3 form a control cavity to ensure that the valve stem can move normally, and a monitoring device is set at the position corresponding to the test rod 10 outside the valve body 1 to monitor the movement of the test rod 10, thereby obtaining the movement state of the valve stem 3.

[0035] In other embodiments, the test rod 10 can be processed into an integral structure with the valve stem 3 or can be fixedly connected by threads and move synchronously with the valve stem 3 .

[0036] In other embodiments, the monitoring device may be a laser sensor or a linear sensor, or may use a high-speed camera or other device to monitor the movement of the test rod 10 in real time.

[0037] In a preferred embodiment, a test rod sliding seal ring 9 is provided between the test rod 10 and the right valve sleeve 4 to ensure sealing between the inside of the valve body 1 and the outside.

[0038] In other embodiments, other sliding seals may be used between the test rod 10 and the right valve sleeve 4 to ensure sealing between the valve body 1 and the outside.

[0039] In a preferred embodiment, the diameter of the test rod 10 is no more than one fifth of the diameter of the valve stem. The test rod 10 has little effect on the self-retaining area ratio of the valve stem 3 and basically does not affect the movement force and position retention ability of the valve stem 3, thereby ensuring that the test results are more accurate.

[0040] In a preferred embodiment, only a low-pressure chamber T connected to the system oil tank and a high-pressure chamber P connected to the accumulator are provided in the valve body 1, and the control valve does not discharge oil to the outside, so that the valve stem is not affected by external forces, which can make the test results more accurate.

[0041] In other embodiments, the control chamber Z communicating with the rodless chamber of the hydraulic cylinder may also be retained in the valve body 1 , without affecting the overall test result of the valve stem 3 .

[0042] In a preferred embodiment, an opening pilot valve 7 and a closing pilot valve 8 are installed on the valve body 1 to control the opening and closing operations of the control valve.

[0043] The specific implementation of the control valve stem motion state testing device of the present invention is as follows: The valve stem 3 and the left valve sleeve 2 and the right valve sleeve 4 respectively form a cone valve. The valve stem 3 can reciprocate in the left valve sleeve 2 and the right valve sleeve 4. The two stop positions of the valve stem 3 are the valve port positions of the two cone valves respectively. The valve stem 3 is equipped with a first sliding sealing ring 5 and a second sliding sealing ring 6. The first sliding sealing ring 5 divides the left valve sleeve 2 into two oil chambers A and B, wherein the A chamber is normally high-pressure oil, and the B oil chamber is connected to the T chamber on the valve body 1 and is low-pressure oil; the second sliding sealing ring 6 divides the right valve sleeve 4 into two oil chambers C and D, wherein the D oil chamber is connected to the P chamber on the valve body 1 and is normally high-pressure oil, and the C chamber is the control chamber for the movement of the valve stem, which is connected to the oil chamber E on the valve body 1, and the oil chamber E is connected to the opening pilot valve 7 and the closing pilot valve 8. When the control valve is performing an opening operation, the opening pilot valve 7 is actuated to release the pressure in the oil chamber C through the oil chamber E, and the valve stem 3 is subjected to a rightward hydraulic force, thereby moving to the right, thereby realizing an opening operation; when performing a closing operation, the closing pilot valve 8 is actuated to inject high-pressure oil into the oil chamber C through the oil chamber E, and the valve stem 3 is subjected to a leftward hydraulic force at this time, thereby moving to the left, thereby realizing a closing operation; the test rod 10 moves synchronously with the valve stem 3, and the movement state of the valve stem 3 is obtained by monitoring the movement of the test rod 10, thereby realizing a test on the switching state of the valve stem 3, and the switching stability of the control valve can be obtained through repeated tests.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A control valve stem motion state testing method, characterized in that: The method is to test a test valve equivalent to the corresponding control valve, the test valve comprising a valve body, a valve stem and a valve sleeve, a test rod being connected to one end of the valve stem, the test rod passing through the valve body and slidingly sealingly cooperating with the valve body, a control cavity being enclosed between the test rod, the valve body and the corresponding ends of the valve stem, a monitoring device being provided at a position outside the valve body corresponding to the test rod to monitor the movement state of the test rod and thereby obtain the movement state of the valve stem.

2. The control valve stem motion state testing method according to claim 1 is characterized in that: A sliding sealing ring is provided between the test rod and the valve sleeve for slidingly sealing between the test rod and the valve sleeve.

3. The control valve stem motion state testing method according to claim 1 is characterized in that: The diameter of the test rod is no greater than one fifth of the diameter of the valve stem.

4. The control valve stem motion state testing method according to any one of claims 1 to 3, characterized in that: The valve body is provided with a low-pressure chamber for communicating with the oil tank and a high-pressure chamber for communicating with the accumulator.

5. The control valve stem motion state testing method according to any one of claims 1 to 3, characterized in that: An opening pilot valve and a closing pilot valve are arranged on the valve body.

6. A control valve stem motion state test device, which is a test valve equivalent to the corresponding control valve, including a valve body, a valve stem and a valve sleeve, characterized in that: A test rod is connected to one end of the valve stem. The test rod passes through the valve body and cooperates with the valve body in a sliding seal. A control cavity is formed between the test rod, the valve body and the corresponding ends of the valve stem. A monitoring device is provided at a position outside the valve body corresponding to the test rod to monitor the movement state of the test rod.

7. The control valve stem motion state testing device according to claim 6, characterized in that: A sliding sealing ring is provided between the test rod and the valve sleeve for slidingly sealing between the test rod and the valve sleeve.

8. The control valve stem motion state testing device according to claim 6, characterized in that: The diameter of the test rod is no greater than one fifth of the diameter of the valve stem.

9. The control valve stem motion state testing device according to any one of claims 6 to 8, characterized in that: The valve body is provided with a low-pressure chamber for communicating with the oil tank and a high-pressure chamber for communicating with the accumulator.

10. The control valve stem motion state testing device according to any one of claims 6 to 8, characterized in that: An opening pilot valve and a closing pilot valve are arranged on the valve body.

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