An in-service valve closing action test structure for an axial flow check valve

Abstract

The present invention discloses an in-service closing valve action test structure for an axial flow check valve in the field of on-line valve detection. A guide rod is connected to the medium pressure-bearing surface of the valve flap. The guide rod is inserted into a guide rod hole. A test hole communicating with the guide rod hole is provided on the fairing. A test interface is provided at a position corresponding to the test hole on the valve body. At the same time, a plurality of drainage holes are opened on the fairing. One end of the drainage hole is connected to the guide rod hole, and the other end leads to the medium pressure-bearing surface of the valve flap. The present invention can conveniently and efficiently detect and test the closing valve action of the axial flow check valve.

Description

Technical Field

[0001] The present invention relates to a test structure for the in-service closing valve action of an axial flow check valve in the field of valve testing. Background Art

[0002] Generally, for the performance test of the action of a check valve that operates relying on the medium force, the valve to be tested needs to be installed on a special test bench for testing. For equipment with the valve and pipeline welded together, each time during maintenance, it is necessary to cut and weld the pipeline and the valve. For nuclear power plants or some important equipment, the test window time is too long, and the welding, non-destructive testing and test cycle after the valve is reset are too complex, and the risk is relatively high. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a test structure for the in-service closing valve action of an axial flow check valve, which can conveniently and efficiently detect and test the closing valve action of the axial flow check valve.

[0004] A technical solution to achieve the above purpose is: a test structure for the in-service closing valve action of an axial flow check valve, including a valve body and a valve flap located in the valve cavity, and the valve flap is connected to a fairing;

[0005] In the middle of the medium pressure-bearing surface of the valve flap, a guide rod is connected. The guide rod is inserted into a guide rod hole arranged inside the valve cavity. On the fairing, a test hole communicating with the guide rod hole is provided radially. At the position corresponding to the test hole on the valve body, a test interface connected to the test hole is provided. At the same time, a plurality of drainage holes are opened on the fairing. One end of the drainage hole is connected to the guide rod hole, and the other end leads to the medium pressure-bearing surface of the valve flap.

[0006] Further, a gap is left between the end of the guide rod and the bottom of the guide rod hole, and the guide rod does not block the test hole.

[0007] Further, a return spring is provided on the guide rod, and the two ends of the guide rod are connected through the return spring.

[0008] An in-service closing valve action test structure for an axial flow check valve of the present invention is achieved by providing a suitable medium and pressure input channel on the fairing of the axial flow check valve and connecting it to the test interface on the valve body. This channel can directly feedback the medium and pressure input from outside the valve to the back of the valve disc and the end of the guide rod. The test medium force drives the valve disc and the guide rod to close, thus meeting the requirement of conveniently detecting the flexible movement of the valve disc without removing the valve equipment from the pipeline system. After the test is completed, simply isolate the test interface, and the valve can resume normal operation. This in-service test structure is simple, and all test channels are arranged inside the pressure-bearing area (except for the interfaces). The installation and operation are simple, significantly reducing the in-service maintenance cycle and improving the system utilization rate.

[0009] An in-service closing valve action test structure for an axial flow check valve of the present invention has the following advantages:

[0010] 1) The test system structure is simple and compact, and the operation during in-service test is convenient.

[0011] 2) No dedicated test system is required.

[0012] 3) There is no need to remove the valve from the pipeline system.

[0013] 4) The maintenance window time is saved.

[0014] 5) The maintenance cost is reduced.

[0015] 6) After adopting this structure, the in-service test can be directly carried out on the pipeline system for detection, so the test results are more reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of an in-service closing valve action test structure for an axial flow check valve of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] In order to better understand the technical solution of the present invention, the following is a detailed description through specific embodiments:

[0018] Please refer to Figure 1, a structure for testing the closing valve action of an axial flow check valve according to the present invention, wherein the valve flap 1 is connected to the fairing 2, and a guide rod 3 is connected to the middle of the medium bearing surface of the valve flap 1. The guide rod 3 is inserted into a guide rod hole 4 provided inside the valve cavity. A test hole 5 communicating with the guide rod hole 4 is radially opened on the wider support rib of the fairing 2, and a test interface 6 connected to the test hole 5 is provided at the corresponding position on the valve body. The function of the test interface 6 is to communicate with an external medium input source during the closing valve action test of the check valve to provide a test medium with stable pressure. A gap is left between the end of the guide rod 3 and the bottom of the guide rod hole 4, and the guide rod 3 does not block the test hole 5. A return spring 8 is provided on the guide rod 3, and both ends of the guide rod 3 are connected through the return spring 8. At the same time, 3 drainage holes 7 (not all shown in the figure) are opened on the fairing 2. One end of the drainage hole 7 is connected to the guide rod hole 4, and the other end leads to the medium bearing surface of the valve flap 1, so that the test medium input through the test interface 6 can directly act on the medium bearing surface of the valve flap 1 through the drainage hole 7.

[0019] The valve flap 1 is in the normally open state under normal working conditions before the test starts. When conducting the closing valve action test, the test medium is input through the test interface 6 on the valve body into the test hole 5 and enters the inside of the valve cavity. A part of the medium enters the guide rod hole 4, and a piston cavity is formed between the guide rod hole 4 and the guide rod 3. The pressure of the test medium pushes the guide rod 3 to move in the direction of closing the valve flap 1. Another part of the test medium enters the drainage hole 7, and the high-speed moving test medium rushes out from the drainage hole 7, and its impact force directly acts on the medium bearing surface of the valve flap 1, driving the valve flap 1 to move in the direction of closing the valve. Under the combined action of the above two forces, the valve flap 1 performs the closing valve action. After the in-service test is completed, the input of the test medium is cut off, and the valve flap assembly is reset under the action of the return spring 8.

[0020] Those of ordinary skill in the art in this technical field should recognize that the above embodiments are only used to illustrate the present invention, rather than to limit the present invention. As long as within the scope of the substantial spirit of the present invention, changes and modifications to the above-described embodiments will fall within the scope of the claims of the present invention.

Claims

1. An in-service closing valve action test structure for an axial flow check valve, comprising a valve body and a valve flap located in the valve cavity. The valve flap is connected to a fairing, and is characterized in that: A guide rod is connected to the middle of the medium bearing surface of the valve flap. The guide rod is inserted into a guide rod hole provided inside the valve cavity. A test hole communicating with the guide rod hole is provided radially on the fairing. A test interface connected to the test hole is provided at a position corresponding to the test hole on the valve body. At the same time, a plurality of drainage holes are provided on the fairing. One end of the drainage hole is connected to the guide rod hole, and the other end leads to the medium bearing surface of the valve flap; A gap is left between the end of the guide rod and the bottom of the guide rod hole, and the guide rod does not close the test hole.

2. The in-service valve closing action test structure of an axial flow check valve according to claim 1, characterized in that, A return spring is provided on the guide rod, and the two ends of the guide rod are connected by the return spring.

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