Axial-flow type check valve performance testing device and testing method thereof

Abstract

The invention relates to the field of valve testing and overhauling, in particular to an axial-flow type check valve performance testing device and a testing method thereof.The device comprises a hydraulic system test bed, a testing water tank, a check valve fixing tool and a heating water tank, one end of the hydraulic system test bed is connected with the heating water tank, and the other end of the hydraulic system test bed is connected with a check valve; the hydraulic system test bench controls the flow of fluid flowing into the check valve in the heating water tank, and the check valve fixing tool is used for fixing the check valve in the test water tank. The device can replace a mechanical test method to perform offline test on the check valve, and can simulate working conditions such as medium pressure, flow, temperature and the like during online operation during test by controlling the flow of the water injection pump and adjusting the temperature of the heating water tank.

Description

Technical Field

[0001] The present invention relates to the field of valve testing and maintenance, and particularly to a performance testing device for an axial flow check valve and a testing method thereof. Background Art

[0002] A system check valve is a valve that relies on the pressure of the medium to generate an action to block the reverse flow of the medium. After the check valve is disassembled and repaired, its performance needs to be tested to verify whether its various performances meet the requirements. Two axial flow welded check valves are connected in series on the outlet pipeline of the core makeup water tank of a third-generation nuclear power unit, and its outlet is connected to the pressure vessel injection pipeline. The valve is in an open state. Under accident conditions, the two core makeup water tanks provide a long-term cooling injection flow to the pressure vessel through the pressure vessel injection pipeline. The check valve has the function of preventing reverse flow and closing, and can prevent the bypass flow from entering the core makeup water tank during the safety injection of the safety injection tank. According to the in-service test requirements, the check valve needs to be tested offline during each refueling outage overhaul, and then tested online after the offline test is successful. It is necessary to test its various characteristics such as action performance, pressure resistance performance, and sealing performance, and the failed check valve should be repaired or replaced.

[0003] In the prior art, the factory uses a mechanical test method for the offline test of this valve. This method can only simulate the force on the check valve under rated conditions. Since the medium and temperature conditions during the test are quite different from the online conditions, this test cannot rule out the possibility that the valve internals get stuck under the online conditions and cause the valve action to fail. Summary of the Invention

[0004] The present invention provides a performance testing device for an axial flow check valve and a testing method thereof, which are used to solve the problem that there are measurement errors in the offline performance test of the check valve in the prior art due to the large differences in medium and temperature conditions from the online conditions.

[0005] The technical solution of the present invention is as follows:

[0006] The present invention proposes a performance testing device for an axial flow check valve. The device includes a hydraulic system test bench, a test water tank, a check valve fixing tooling, and a heating water tank. One end of the hydraulic system test bench is connected to the heating water tank, and the other end of the hydraulic system test bench is connected to the check valve. The hydraulic system test bench controls the flow rate of the fluid flowing from the heating water tank into the check valve. The check valve fixing tooling is used to fix the check valve in the test water tank.

[0007] In some embodiments, the hydraulic system test bench includes a gas-driven control circuit, a water injection pump, and a water injection pipeline. The water injection pump is respectively connected to the heating water tank and the check valve through the water injection pipeline; the water injection pump is connected to the gas-driven control circuit, and the gas-driven control circuit is used to control the flow rate of the water injection pump.

[0008] In some embodiments, the test water tank provides a test environment where the check valve is immersed underwater, and the check valve is submerged in the test water tank during the test.

[0009] In some embodiments, the check valve fixing tooling includes an inlet blind plate, an outlet blind plate and a number of screws. The inlet blind plate and the outlet blind plate are respectively arranged at the inlet and outlet of the check valve, and the inlet blind plate and the outlet blind plate are connected by a number of screws.

[0010] In some embodiments, the screws are circumferentially distributed outside the check valve. The screws connect the inlet blind plate and the outlet blind plate through nuts and gaskets. The screws apply a sealing pressure between the check valve and the blind plates. O-rings are used for sealing at the connections between the check valve and the inlet blind plate and the outlet blind plate. Threaded holes are opened in the centers of the inlet blind plate and the outlet blind plate for connecting with the water injection pipeline and the drainage pipeline.

[0011] In some embodiments, the heating water tank is used to heat the fluid for testing, and the heating water tank simulates the temperature environment of the core makeup water tank of the nuclear power plant unit.

[0012] In some embodiments, the air-driven control loop includes an air filter, a gas pressure regulator, a drive stop valve and pipelines. From the air inlet to the injection water pump, the air filter, the gas pressure regulator and the drive stop valve are sequentially connected through pipelines. A pressure gauge is provided on the gas pressure regulator. A water filter and a water inlet stop valve are provided on the water injection pipeline between the injection water pump and the heating water tank. A flow meter and a pressure gauge are provided on the water injection pipeline between the injection water pump and the check valve.

[0013] In some embodiments, the heating water tank is connected to the water injection pipeline between the injection water pump and the check valve through a pressure relief pipeline, and a pressure relief valve is provided on the pressure relief pipeline.

[0014] The present invention proposes a method for testing the performance of an axial flow check valve, and the method includes:

[0015] Step 1: Set up the performance test device for the axial flow check valve;

[0016] Step 2: Fix the check valve using the check valve fixing tooling, and hoist and submerge the check valve in the test water tank;

[0017] Step 3: Start the injection water pump of the hydraulic system test bench, and check to ensure that the functions of the hydraulic system test bench are normal;

[0018] Step 4: Use the injection water pump to inject water into the check valve until the rated pressure for the check valve to close is reached, observe whether the check valve closes normally and record the water injection flow rate at the time of closing, and test the closing action performance and sealing performance of the check valve;

[0019] Step 5: Increase the pressure of the check valve by increasing the water injection flow rate of the injection water pump, observe whether the check valve leaks or deforms, and test the pressure resistance performance of the check valve;

[0020] Step 6: Reduce the water injection flow rate of the water injection pump, observe whether the check valve opens automatically, and test the pressure resistance performance of the check valve.

[0021] In some embodiments, the specific steps for building the axial flow check valve performance test device in Step 1 are as follows: Connect the water injection pipeline of the hydraulic system test bench to the heating water tank and the check valve inlet, connect the gas drive control loop of the hydraulic system test bench to the on-site gas source pipeline, and connect the check valve outlet back to the test water tank.

[0022] Implementing the present invention has the following beneficial effects

[0023] The present invention provides an axial flow check valve performance test device and a test method thereof. The present invention can replace the mechanical test method to perform off-line tests on this type of check valve. By controlling the flow rate of the water injection pump and adjusting the temperature of the heating water tank, the medium pressure, flow rate, temperature and other working conditions during on-line operation can be simulated during the test. Compared with the current mechanical test method, it has higher credibility and can more reliably and comprehensively verify the effect of off-line disassembly and repair of the valve, which is beneficial for improving the off-line maintenance test efficiency, reducing the on-line test time, and shortening the overhaul period. Description of the Drawings

[0024] Figure 1 Schematic diagram of the hydraulic system test bench loop of an axial flow check valve performance test device proposed in an embodiment of the present invention;

[0025] Figure 2 Schematic diagram of the hydraulic system test bench of an axial flow check valve performance test device proposed in an embodiment of the present invention;

[0026] Figure 3 Schematic diagram of the test water tank of an axial flow check valve performance test device proposed in an embodiment of the present invention;

[0027] Figure 4 Schematic diagram of the check valve fixing tooling of an axial flow check valve performance test device proposed in an embodiment of the present invention;

[0028] Figure 5 Schematic diagram of the heating water tank of an axial flow check valve performance test device proposed in an embodiment of the present invention;

[0029] Description of the Drawings: 1. Hydraulic system test bench; 2. Test water tank; 3. Check valve fixing tooling; 4. Heating water tank; 5. Inlet blind plate; 6. Screw; 7. Check valve; 8. Outlet blind plate. Detailed Embodiments

[0030] The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] As Figures 1 to 5 shown, the present invention provides a performance test device for an axial flow check valve. The device includes a hydraulic system test bench 1, a test water tank 2, a check valve fixing tooling 3, and a heating water tank 4. One end of the hydraulic system test bench 1 is connected to the heating water tank 4, and the other end of the hydraulic system test bench 1 is connected to the check valve 7. The hydraulic system test bench 1 controls the flow rate of the fluid flowing from the heating water tank 4 into the check valve 7. The check valve fixing tooling 3 is used to fix the check valve 7 in the test water tank 2.

[0032] As Figure 2 shown, the hydraulic system test bench 1 includes a pneumatic drive control circuit, a water injection pump, and a water injection pipeline. The water injection pump is respectively connected to the heating water tank 4 and the check valve 7 through the water injection pipeline; the water injection pump is connected to the pneumatic drive control circuit, and the pneumatic drive control circuit is used to control the flow rate of the water injection pump. The hydraulic system test bench 1 is equipped with a pneumatic large-flow water injection pump, which is used to increase the water injection flow rate by adjusting the driving air pressure until the check valve 7 automatically closes during the closing action performance test, so as to meet the flow rate and pressure supply requirements during the closing action process of the check valve 7. The pneumatic drive control circuit includes an air filter, a gas pressure regulator, a drive stop valve, and pipelines. From the air inlet to the water injection pump, the air filter, the gas pressure regulator, and the drive stop valve are sequentially connected through pipelines. A pressure gauge is provided on the gas pressure regulator; a water filter and a water inlet stop valve are provided on the water injection pipeline between the water injection pump and the heating water tank 4, and a flow meter and a pressure gauge are provided on the water injection pipeline between the water injection pump and the check valve 7. The heating water tank 4 is connected to the water injection pipeline between the water injection pump and the check valve 7 through a pressure relief pipeline, and a pressure relief valve is provided on the pressure relief pipeline. The manual operation switches of the above-mentioned display instruments and various valves are integrated on the test bench panel for the convenience of users to operate and observe.

[0033] As Figure 3 shown, the test water tank 2 is used to provide a test environment for the check valve 7 to be tested immersed in water. During the test, the check valve 7 to be tested and the fixing device are placed in the test water tank 2.

[0034] As Figure 4As shown in the figure, the check valve fixing tooling 3 includes an inlet blind plate 5, an outlet blind plate 8, a screw 6, nuts, gaskets and O-ring seals. The check valve 7 to be tested is provided with an inlet blind plate 5 and an outlet blind plate 8 at the inlet and outlet. A circumferentially distributed screw 6 is arranged between the two blind plates. The blind plates are tightened by the screw 6, nuts and gaskets to apply a sealing pressure between the valve to be tested and the blind plates. The connection between the check valve 7 to be tested and the inlet and outlet blind plates 8 is sealed with an O-ring. Threaded holes are opened in the center of the inlet blind plate 5 and the outlet blind plate 8 to serve as the interfaces for the water injection pipeline and the drainage pipeline. These interfaces can be blocked with threaded plugs when necessary.

[0035] As Figure 5 shown in the figure, the heating water tank 4 is used to heat the test loop, and the heating water tank 4 simulates the temperature environment of the core makeup water tank of the nuclear power plant unit.

[0036] The present invention provides a method for testing the performance of an axial flow check valve 7, and the method includes:

[0037] Step 1: Connect the heating water tank 4 and the check valve 7 using the water injection pipeline of the hydraulic system test bench 1, and connect the air-driven control loop of the hydraulic system test bench 1 to the on-site gas source pipeline. Specifically, connect the driving air inlet of the air-driven control loop of the test system to the on-site gas source pipeline. The water inlet of the water injection pipeline of the hydraulic system test bench 1 is connected to the water outlet of the heating water tank 4 through a quick-insert hose. Connect the water injection pipeline of the hydraulic system test bench 1 to the inlet of the check valve 7 to be tested through the output pipeline, and connect the outlet of the check valve 7 to be tested back to the test water tank 2 through the drainage pipeline;

[0038] Step 2: Fix the check valve 7 using the check valve fixing tooling 3 and hoist and immerse the check valve 7 in the test water tank 2. Specifically: Use the check valve fixing tooling 3 to clamp the inlet and outlet of the check valve 7 in opposite directions to achieve sealing between the valve body end face and the plug plate; Install the hoisting and fixing frame, and use a lifting tool and a crane to hoist the valve body into the test water tank 2 to ensure that the entire valve body of the check valve 7 is immersed below the water surface.

[0039] Step 3: Start the water injection pump of the hydraulic system test bench 1 and check to ensure that the functions of the hydraulic system test bench 1 are normal. Specifically: Open the drive stop valve, the inlet stop valve, and the unloading valve, and clockwise adjust the gas pressure regulating valve to start the water injection pump. Check that the functions of the pump, flow meter, and digital display pressure gauge should be normal.

[0040] Step 4: Use a water injection pump to inject water into the check valve 7 until it reaches the rated pressure for the check valve 7 to close. Observe whether the check valve 7 closes normally and record the water injection flow rate at the time of closing to test the closing action performance and sealing performance of the check valve 7. Specifically: Close the unloading valve and the outlet blind plate of the check valve 7 body, and open the water injection pipeline of the inlet blind plate of the valve body; continue to adjust the gas pressure regulating valve to increase the driving air pressure and the water injection flow rate. After reaching the rated pressure for the check valve 7 to close, maintain for a period of time. Determine whether the check valve 7 can close normally after reaching the closing pressure by observing the flow rate of the flowmeter, which is used for evaluating the closing action performance. At the same time, record the flow rate at this time (i.e., the leakage rate) for evaluating the sealing performance.

[0041] Step 5: Increase the pressure of the check valve 7 by increasing the water injection flow rate of the water injection pump, and observe whether the check valve 7 leaks or deforms to test the pressure resistance performance of the check valve 7. Specifically: Continue to increase the pressure to a certain value and maintain for a period of time, and observe whether the check valve 7 to be tested leaks or deforms to evaluate the pressure resistance performance.

[0042] Step 6: Reduce the water injection flow rate of the water injection pump and observe whether the check valve 7 opens automatically to test the pressure resistance performance of the check valve 7. Specifically: Close the driving stop valve, open the unloading valve, and open the outlet plug of the valve body to make the check valve 7 reach the pressure for automatic opening, and check whether the check valve 7 is in the open position for evaluating the opening action performance.

[0043] The present invention can replace the mechanical test method to perform off-line testing on this type of check valve 7. During the test, it can simulate the working conditions such as the medium pressure, flow rate, and temperature during on-line operation. Compared with the current mechanical test method, it has higher credibility and can more reliably and comprehensively verify the effect of off-line disassembly and repair of the valve, which is beneficial for improving the off-line repair test efficiency, reducing the on-line test time, and shortening the overhaul period.

[0044] The above embodiments only represent several implementation manners of the present invention, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. An axial flow check valve performance testing device, characterized in that: The device comprises a hydraulic system test bench (1), a test water tank (2), a check valve fixing tool (3) and a heating water tank (4); one end of the hydraulic system test bench (1) is connected to the heating water tank (4), and the other end of the hydraulic system test bench (1) is connected to the check valve (7); the hydraulic system test bench (1) controls the flow rate of the fluid in the heating water tank (4) flowing into the check valve (7); and the check valve fixing tool (3) is used to fix the check valve (7) in the test water tank (2).

2. The axial flow check valve performance testing device according to claim 1, characterized in that: The hydraulic system test bench (1) comprises an air-driven control circuit, a water injection pump and a water injection pipeline, wherein the water injection pump is respectively connected to the heating water tank (4) and the check valve (7) through the water injection pipeline; the water injection pump is connected to the air-driven control circuit, and the air-driven control circuit is used to control the flow rate of the water injection pump.

3. The axial flow check valve performance testing device according to claim 1, characterized in that: The test water tank (2) provides an underwater testing environment for the check valve (7); during testing, the check valve (7) is immersed in the test water tank (2).

4. The axial flow check valve performance testing device according to claim 1, characterized in that: The check valve fixing fixture (3) comprises an inlet blind plate (5), an outlet blind plate (8) and a plurality of screw rods (6); the inlet blind plate (5) and the outlet blind plate (8) are respectively provided at the inlet and the outlet of the check valve (7); the inlet blind plate (5) and the outlet blind plate (8) are connected via the plurality of screw rods (6).

5. The axial flow check valve performance testing device according to claim 4, characterized in that: The screw (6) is circumferentially distributed on the outside of the check valve (7); the screw (6) is connected to the inlet blind plate (5) and the outlet blind plate (8) through a nut and a gasket; the screw (6) applies sealing pressure between the check valve (7) and the blind plate; an O-ring seal is provided at the connection between the check valve (7) and the inlet blind plate (5) and the outlet blind plate (8); threaded holes are provided in the center of the inlet blind plate (5) and the outlet blind plate (8); the threaded holes are used to connect to a water injection pipeline and a drainage pipeline.

6. The axial flow check valve performance testing device according to claim 1, characterized in that: The heating water tank (4) is used to heat the fluid for testing, and the heating water tank (4) simulates the temperature environment of the core water supply tank of a nuclear power plant unit.

7. The axial flow check valve performance testing device according to claim 2, characterized in that: The air drive control circuit comprises an air filter, a gas pressure regulator, a driving stop valve and a pipeline. The air filter, the gas pressure regulator and the driving stop valve are connected in sequence from the air inlet of the air drive control circuit to the water injection pump through a pipeline, and a pressure gauge is provided on the gas pressure regulator; a water filter and a water inlet stop valve are provided on the water injection pipeline between the water injection pump and the heating water tank (4), and a flow meter and a pressure gauge are provided on the water injection pipeline between the water injection pump and the check valve (7).

8. The axial flow check valve performance testing device according to claim 7, characterized in that: The heating water tank (4) is connected to the water injection pipeline between the water injection pump and the check valve (7) through a pressure relief pipeline, and a pressure relief valve is provided on the pressure relief pipeline.

9. A method for testing the performance of an axial flow check valve according to any one of claims 1 to 8, characterized in that: The method comprises: Step 1: Building an axial flow check valve (7) performance test device; Step 2: Use the check valve fixing tool (3) to fix the check valve (7), and hang the check valve (7) to immerse it in the test water tank (2); Step 3: Turn on the water injection pump of the hydraulic system test bench (1) to check and ensure that the hydraulic system test bench (1) functions normally; Step 4: Use the water injection pump to inject water into the check valve (7) to reach the rated pressure for closing the check valve (7), observe whether the check valve (7) is closed normally and record the water injection flow rate when closed, and test the closing action performance and sealing performance of the check valve (7); Step 5: increasing the water injection flow rate of the water injection pump to increase the pressure of the check valve (7), observing whether the check valve (7) leaks or deforms, and testing the pressure resistance of the check valve (7); Step 6: Reduce the water injection flow rate of the water injection pump, observe whether the check valve (7) opens automatically, and test the pressure resistance performance of the check valve (7).

10. The method for testing the performance of an axial flow check valve according to claim 9, characterized in that: The axial flow check valve performance test device in step 1 is specifically constructed by using the water injection pipeline of the hydraulic system test bench (1) to connect the heating water tank (4) and the check valve (7) inlet, using the air drive control circuit of the hydraulic system test bench (1) to connect the on-site air source pipeline, and the check valve (7) outlet is connected back to the test water tank (2) through a drainage pipeline.

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