CN107179169A - A kind of nuclear power station check valve action test set and test method - Google Patents

Abstract

The invention provides a test device for a check valve of a nuclear power plant, which is used for the sealing performance test of a check valve of a safety injection pipeline, including an upstream pipeline, a downstream pipeline, a high-pressure introduction component and a pressure detection piece. On the other hand, the present invention also provides a nuclear power plant check valve test method, which introduces the pressure of the waste heat discharge system of the primary circuit into the check valve pipeline through the high-pressure introduction component, so that the check valve pipeline can be realized without starting the low-pressure safety injection pump. The purpose of pressure induction is to greatly reduce the risk of the test; at the same time, the pressure detection part is used to replace the traditional instrument, and the high-pressure instrument hose is used to connect the pressure gauge. The installation position of the pressure gauge is more flexible, thereby improving the readability of the instrument and reducing the reading error.

Description

A nuclear power plant check valve test device and test method

technical field

The invention relates to the technical field of sealing performance test of a check valve of a safety injection pipeline of a pressurized water reactor nuclear power plant, in particular to a test device and a test method applied to a test of the tightness of a check valve of a safety injection pipeline of a pressurized water reactor nuclear power plant.

Background technique

Safety injection system (referred to as RIS) and reactor cooling system (also known as primary circuit, referred to as RCP) are the key systems of the nuclear island. Safety injection system for remediation to ensure the safe operation of nuclear power plant reactors.

The safety injection pipeline of nuclear power plant is designed with a series of non-return valves to form the isolation boundary of the primary circuit. stop valve. The good sealing of the check valve of the safety injection pipeline is an important guarantee for maintaining the integrity of the pressure boundary of the primary circuit. The sealing performance of the check valve of the safety injection line is particularly important, so a series of tests need to be performed to verify its tightness.

At present, for the check valve sealing test, it is necessary to artificially create pressure by starting the low-pressure safety injection pump and introduce the pressure into the check valve pipeline, and then isolate and observe the pressure rise of the upstream pipeline after the upstream pressure relief of the check valve to judge the check valve of tightness. Among them, it is necessary to weld a temporary pipeline on the pressure monitoring pipeline in advance, and then connect a temporary pressure gauge through the temporary pipeline to detect pressure changes.

Since the test process needs to manually start the low-pressure safety injection pump, it not only increases the workload and construction period of the staff, but also increases the risks of running water, equipment damage, and personal injury during the test. The entire test process also requires the installation of a large number of high-precision instruments at the pressure detection position in advance. Not only is the installation and removal workload heavy, but the long-term installation on site also increases the probability of instrument damage, resulting in increased test costs. In addition, due to the limitation of on-site installation conditions, the installation position of the meter is not very convenient for reading, resulting in a large error in the reading of the meter.

Contents of the invention

The technical problem to be solved by the present invention is: in view of the prior art, the low-pressure safety injection pump needs to be artificially activated for the check valve sealing test, which increases the risk of equipment damage and personal injury during the test, and a large number of high-precision instruments need to be installed on site A test device and a test method for a check valve of a safety injection pipeline of a nuclear power plant with higher test efficiency and lower cost without starting a low-pressure safety injection pump are provided to solve problems such as an increase in test cost.

The technical scheme proposed by the present invention with respect to the above technical problems is as follows: on the one hand, a nuclear power plant check valve test device is provided, comprising:

Upstream pipeline for connection to the safety injection system;

Downstream piping for connection to the reactor coolant system;

A first check valve, connected between the upstream line and the downstream line, further comprising:

The high-pressure introduction component is connected between the waste heat discharge system of the primary circuit and the pipeline downstream of the first check valve, and is used to introduce the pressure of the waste heat discharge system of the primary circuit from high pressure and reduce the high pressure to the first check valve. The test pressure of a check valve is delivered to the pipeline downstream of the first check valve;

A pressure detection part, connected to the downstream pipeline or upstream pipeline of the first check valve, used to detect the test pressure of the first check valve and detect the pressure of the first check valve during the sealing test. The pressure change of the pipeline downstream or upstream of the first check valve.

Wherein, the condition for introducing high pressure is: before performing the sealing test on the first check valve, the connection between the upstream pipeline and the safety injection system and the connection between the downstream pipeline and the reactor coolant system are respectively cut off.

Wherein, the high-pressure introduction assembly includes a high-pressure hose and a first valve assembly and a second valve assembly respectively connected at both ends of the high-pressure hose;

One end of the high-pressure introduction component is connected to the main line of the primary circuit waste heat discharge system through the first valve component, and the other end is connected to the downstream pipeline of the first check valve through the second valve component. The second valve component for venting said high pressure to a test pressure of said first check valve and into a pipeline downstream of said first check valve;

Wherein, the pressure detection part includes:

A pressure detection female head assembly, connected to the upstream pipeline of the first check valve;

A pressure detection sub-head assembly, which is pluggably connected to the female head assembly, and is used to detect the test pressure of the first check valve and to detect the first check valve during the sealing test of the first check valve. If the actual pressure detected is greater than the test pressure and the upstream pressure increases, it is judged that the check valve is leaking.

Wherein, the pressure detection part includes:

A pressure detection female head assembly, connected to the downstream pipeline of the first check valve;

A pressure detection sub-head assembly, which is pluggably connected to the female head assembly, and is used to detect the test pressure of the first check valve and to detect the first check valve during the sealing test of the first check valve. The pressure change of the pipeline downstream of the check valve, if the actual detected pressure is lower than the test pressure and the downstream pressure decreases, it is judged that the check valve has leakage.

Wherein, the other end of the high-pressure hose is also connected with a pressure detection piece, and the pressure detection piece is connected to the downstream pipeline of the first check valve and the third check valve through the second valve assembly, and the pressure detection piece It is connected to the downstream pipeline of the second check valve and the fourth check valve through the third valve assembly.

Wherein, the female head assembly of the pressure detection piece includes:

A female connection, one end of the female connection is connected to a flange, and the flange is connected to a fifth valve, and the fifth valve is connected to an upstream pipeline or a downstream pipeline for opening or closing pipeline pressure;

The pressure detection sub-head assembly includes:

A connecting subhead, one end of the connecting subhead is movably connected to the other end of the connecting female head;

The other end of the connection subhead is connected to a pressure gauge through a first joint, and the pressure gauge is used to detect the actual pressure.

Wherein, the other end of the connecting sub-head is also connected with a second joint, and the second joint is used for connecting a manual shut-off valve, and the manual shut-off valve is connected with a drain exhaust pipe for controlling pipeline pressure relief;

The first connector includes a first female connector and a first sub connector detachably connected to the first female connector;

The second connector includes a second female connector and a second sub connector detachably connected to the second female connector;

The connecting female head is automatically closed when it is empty;

The pressure gauge is connected to the first connector through an instrument high-pressure hose, which is used to place the pressure gauge at a position easy to read.

Wherein, the other end of the high-pressure hose is divided into a first branch and a second branch, the other end of the first branch is connected to a second valve assembly, and the other end of the second valve assembly is connected to the On the pipeline downstream of the first check valve; the other end of the second branch is connected to the third valve assembly, and the other end of the third valve assembly is connected to the downstream pipeline of the second check valve and the fourth check valve superior.

Wherein, the high-pressure hose adopts a high-pressure hose black rubber hose for temporary pressure introduction; the high-pressure hose and the first valve assembly, the second valve assembly, and the third valve assembly all adopt slipknot threads of the same structure joint connection; the slipknot threaded joint is provided with a high-pressure gasket inside, and the high-pressure gasket is used for sealing after compression.

Wherein, the first valve assembly includes a flange and a first valve connected to the flange, and the first valve is used to open or close the pipeline;

The second valve assembly includes: a flange, a second valve connected to the flange, a third valve connected to the second valve, and a fourth valve connected between the second valve and the third valve. valve;

Both the second valve and the third valve are used to open or close the pipeline, and the fourth valve is used to control pipeline pressure relief to reduce the introduced high pressure to the test pressure required by the first check valve.

On the other hand, a test method for a check valve of a nuclear power plant is provided, which is used for a test of the tightness of a check valve of a safety injection pipeline of a nuclear power plant, comprising the following steps:

S1: Drain the high pressure of the primary circuit waste heat discharge system of the nuclear power plant to the test pressure and introduce it to the downstream pipeline of the check valve;

S2: Detect the test pressure of the downstream pipeline or upstream pipeline of the first check valve through a movably connected pressure detection member;

S3: Detect the pressure change of the upstream or downstream pipeline of the first check valve during the test, judge whether the first check valve leaks according to the pressure change state, if the actual pressure detected by the downstream pipeline is less than the test pressure, the downstream If the pressure drops, or the actual pressure detected by the upstream pipeline is greater than the test pressure, and the upstream pressure increases, it is judged that the first check valve is leaking.

Wherein, the pressure detection part is used to detect the pressure change of the downstream pipeline of the first check valve, the second check valve, the third check valve and the fourth check valve, if the detected actual pressure is less than the test pressure, the downstream pressure decreases, and it is judged that one or more of the first check valve, the second check valve, the third check valve and the fourth check valve have leaks.

A nuclear power plant check valve test device and test method provided by the present invention have the following technical effects:

The pressure induction work of the check valve pipeline is realized through the high-pressure introduction component, so that there is no need to start the low-pressure safety injection pump, which improves the test efficiency, and also reduces the multiple risks of equipment damage and personal injury when the low-pressure safety injection pump is started; through pressure detection One end can be used for multiple purposes, which greatly reduces the cost of the test; and the pressure gauge is connected to the pressure gauge through a high-pressure hose, so the pressure gauge can be installed in a position that is more conducive to reading, thereby reducing the reading error and improving the test quality. At the same time, the test method for the check valve provided by the invention makes the test work simpler and improves the test efficiency.

Description of drawings

Fig. 1 is the connection diagram of the check valve test device provided by the present invention;

Fig. 2 is a schematic diagram of the internal structure of the living threaded joint provided by the present invention;

Fig. 3 is a structural schematic diagram of the pressure detection part provided by the present invention;

Fig. 4 is a schematic drawing of the pressure introduction of the high-pressure hose provided by the present invention.

detailed description

In order to solve the problems in the prior art that the low-pressure safety injection pump needs to be started artificially in the check valve sealing test, which increases the risks of equipment damage and personal injury during the test, and the need to install a large number of high-precision instruments on site leads to the increase in test costs, etc., we provide A nuclear power plant safety injection pipeline check valve test device and test method, the core idea of which is: the check valve test device introduces pressure through high-pressure components, thereby eliminating the need to start a low-pressure safety injection pump, improving test efficiency and reducing test risks; The test piece replaces the traditional instrument installation method, realizes multiple functions at one end, greatly reduces the test cost investment, and connects the pressure gauge through a high-pressure hose, the pressure gauge can be installed in a position that is more conducive to reading, thereby reducing reading errors. At the same time, the test method for the check valve provided by the invention makes the test work simpler and improves the test efficiency.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Embodiment one:

Fig. 1 is a schematic connection diagram of the check valve test device, as shown in Fig. 1, the check valve test device includes:

The upstream pipeline 101 is used to connect the safety injection system 100;

a downstream pipeline 102 for connecting to the reactor coolant system 500;

The first check valve 10, connected between the upstream pipeline 101 and the downstream pipeline 102, also includes:

The high-pressure introduction component is connected between the primary circuit waste heat discharge system 700 and the downstream pipeline 102 of the first check valve 10, and is used to introduce the pressure of the primary circuit waste heat discharge system from high pressure and reduce the high pressure to the first The test pressure of a check valve 10 is delivered to said first check valve 10;

The pressure detecting member 130 is connected to the upstream pipeline 101 or the downstream pipeline 102 of the first check valve 10, and is used to detect the test pressure of the first check valve 10 and seal the first check valve 10. During the test, the pressure change of the upstream pipeline 101 or the downstream pipeline 102 is detected.

In the first embodiment, the pressure detecting element 130 is installed on the downstream pipeline 102 .

The high-pressure introduction assembly includes a high-pressure hose 600 and a first valve assembly 610 and a second valve assembly 620 respectively connected to both ends of the high-pressure hose 600;

One end of the high-pressure introduction assembly is connected to the downstream pipeline 102 of the first check valve 10 through the second valve assembly 620 , and the other end is connected to the main line 611 of the waste heat removal system 700 of the primary circuit through the first valve assembly 610 .

The first valve assembly 610 includes a first valve 610a and a flange 610b. One end of the first valve 610a is connected to the main line 611, and the other end is connected to the flange 610b. During the test, the first valve 610a is opened to introduce high pressure from the primary circuit discharge system 700 to realize the pressure induction operation. The other end of the flange 610 b is connected to the high-pressure hose 600 through a live threaded joint 800 .

The second valve assembly 620 includes: a flange 620a, a second valve 620b connected to the flange 620a, a third valve 620c connected to the second valve 620b, and a third valve 620c connected to the second valve 620b and a fourth valve 620d intermediate the third valve 620c;

Both the second valve 620b and the third valve 620c are used to open or close the pipeline, and the fourth valve 620d is used to control the pressure relief of the pipeline, reducing the introduced high pressure to the required level of the first check valve 10. test pressure.

The high-pressure hose 600 adopts a high-pressure hose black rubber hose, which acts as a temporary pressure introduction pipeline, and its maximum withstand pressure is 250 bar. The high-pressure hose 600 is connected to the first valve assembly 610 and the second valve assembly 620 by a slip-knot threaded joint 800 of the same structure.

Further, as shown in FIG. 2, the high-pressure hose 600 and the second valve assembly 620 are connected through a slip joint 800, and a high-pressure gasket 801 is provided inside the slip joint 800, and the high-pressure gasket 801 is used for Play a sealing role after pressing.

Further, as shown in FIG. 3 , the pressure detection member 130 includes:

A pressure detection female head assembly 131, connected to the upstream pipeline 101 or the downstream pipeline 102 of the first check valve 10;

The pressure detection sub-head assembly 132 is pluggably connected with the female head assembly 131.

The pressure detection female head assembly 131 includes:

Connect the female head 135a, one end of the connecting female head 135a is connected to the flange 140, and the flange 140 is connected to the fifth valve 141, and the fifth valve 141 is connected to the upstream pipeline 101 or the downstream pipeline 102 for opening or closing the pipeline .

The pressure detection female head assembly 131 can be installed on site in advance through the threaded connection between the first flange 140a and the second flange 140b. In the vacant state, the connecting female head 135a is automatically closed, and at the same time the fifth valve 141 is closed, and the sealing performance of the upstream pipeline 101 or the downstream pipeline 102 in the vacant state is enhanced through two isolation valves.

The pressure detection sub-head assembly 132 includes:

Connecting sub-head 135b, one end of the connecting sub-head 135b is movably connected to the other end of the connecting female head 135a; the other end of the connecting sub-head 135b is used to connect with the pressure gauge 138 through the first joint 137, The pressure gauge 138 is used to detect the actual pressure.

The other end of the connection sub-head 135b is also connected to a second joint 136, the second joint 136 is used to connect a manual shut-off valve 139, and the manual shut-off valve 139 is connected to the drain pipe 133 for controlling pipeline pressure relief ;

The first connector 137 includes a first female connector 137a and a first sub connector 137a that is pluggably connected to the first female connector 137a; the second connector 136 includes a second female connector 137a and the second sub-head connector 137b that is pluggably connected to the second female connector 137a.

The pressure gauge 138 is connected to the first joint 137 through the instrument high-pressure hose 134, which is used to place the pressure gauge 138 at a position that is easy to read, and has high flexibility, thereby reducing reading errors and improving test quality .

It should be noted that when the pressure detection part 130 is connected to the upstream pipeline 101 of the first check valve 10, the pressure detection part 130 is used to detect the test pressure of the first check valve 10 and the During the sealing test of the first check valve 10, the pressure change of the upstream pipeline 101 of the first check valve is detected. If the detected actual pressure is greater than the test pressure and the upstream pressure increases, it is judged that the first Check valve 10 leaks;

When the pressure detection part 130 is connected to the downstream pipeline 102 of the first check valve 10, the pressure detection part 130 is used to detect the test pressure of the first check valve 10 and the Detect the pressure change of the pipeline 102 downstream of the first check valve during the sealing test of the check valve 10. If the detected actual pressure is less than the test pressure and the downstream pressure decreases, it is judged that the first check valve is reversed. The valve is leaking.

During the execution of the check valve test, the tester can carry the pressure detection sub-head assembly 132 with him, and connect the pressure detection sub-head assembly 132 with the pressure detection female head assembly 131 installed on site in advance according to the test arrangement to form a reverse valve assembly. The temporary pressure gauge device for the check valve tightness test can perform the check valve test operation. After the test is completed, the pressure detection sub-head assembly 132 can be taken off for the next test, so that one end can be used for multiple purposes.

Further, as shown in Figure 4, the pressure introduction operation of multiple check valve sealing tests can be realized simultaneously through the high pressure introduction assembly, including:

A first check valve 10 connected to the pipeline of the first low-pressure safety injection system 100;

The second check valve 20 connected to the pipeline of the second low-pressure safety injection system 200;

A third check valve 30 connected between the first high-pressure safety injection system 300 and the first low-pressure safety injection system 100;

A fourth check valve 40 is connected between the second high-pressure safety injection system 400 and the second low-pressure safety injection system 200 .

One end of the high-pressure component is connected to the main line 611 of the waste heat removal system 700 of the primary circuit through the first valve component 610 , and the other end is divided into a first branch 621 and a second branch 631 .

The first branch 621 is connected to the downstream pipeline of the first check valve 10 and the third check valve 30 through the second valve assembly 620, and the second valve assembly 620 is used to release the high pressure to The test pressures of the first check valve 10 and the third check valve 30 are also introduced into the downstream pipelines of the first check valve 10 and the third check valve 30 .

The second branch 631 is connected to the downstream pipeline of the second check valve 20 and the fourth check valve 40 through a third valve assembly 630, and the third valve assembly 630 is used to release the high pressure to the The test pressures of the second check valve 20 and the fourth check valve 40 are introduced into the downstream pipelines of the second check valve 20 and the fourth check valve 40 .

The other end of the high-pressure hose 600 is also connected to a pressure detection piece 144, and the pressure detection piece 144 is connected to the downstream pipeline of the first check valve 10 and the third check valve 30 through the second valve assembly 620, so The pressure detecting element 144 is connected to the downstream pipelines of the second check valve 20 and the fourth check valve 40 through the third valve assembly 630 .

The pressure detector 144 is used to detect the change of the downstream pipeline pressure of the first check valve 10, the second check valve 20, the third check valve 30 and the fourth check valve 40, if the detected actual pressure is less than The test pressure and the downstream pressure decrease, and it is judged that one or more of the first check valve 10 , the second check valve 20 , the third check valve 30 and the fourth check valve 40 are leaking.

Embodiment two:

The invention also provides a test method for the check valve of the nuclear power plant, which is used for the test of the sealing performance of the check valve of the safety injection pipeline of the nuclear power plant.

It should be noted that the check valve test can be divided into two basic methods, one is to pressurize the downstream of the check valve, isolate the upstream after pressure relief, and use a pressure gauge to monitor the rate of rise of the upstream pressure; After the downstream of the valve is pressurized, it is isolated, and the upstream is depressurized, and the downstream pressure drop rate is monitored with a pressure gauge.

In conjunction with what is shown in Figure 1, the following is a detailed description of the sealing test method that uses the pressure detection assembly 130 to detect whether the upstream pressure increases at the downstream of the first check valve 10 for pressurization and isolation after upstream pressure relief, including the following steps:

S1: Cut off the connection between the upstream pipeline 101 of the first check valve 10 and the first low-pressure safety injection system 100 , and the downstream pipeline 102 and the first reactor cooling system 500 , isolating the upstream pipeline 101 and the downstream pipeline 102 .

S2: Open the first valve 610a, release the high pressure of the primary circuit waste heat discharge system 700 of the nuclear power plant, and lead it to the second valve assembly 620 through the high pressure hose 600 . The introduced high pressure is adjusted to the test pressure of the first check valve 10 through the fourth valve 620d, and then introduced to the downstream pipeline 102 of the first check valve 10, and the second valve 620b and the second valve 620b are closed after the introduction of pressure is completed. The third valve 620c.

S3: Reduce the pressure of the upstream pipeline 101 of the first check valve 10 to 17 Bar.g through the manual shut-off valve 139 (this pressure criterion is set when the low-pressure safety injection pump is started to induce pressure, and the outlet pressure of the low-pressure safety injection pump Slightly greater than 17 bar.g), the pressure change on the upstream pipeline 101 is detected by the pressure detecting element 130 arranged on the upstream pipeline 101.

S4: Judging whether the first check valve 10 leaks according to the pressure change state, if the detected actual pressure is greater than the test pressure, the pressure of the upstream pipeline 101 increases, and it is judged that the first check valve 10 has leakage.

Further, in conjunction with FIG. 4 , the following describes in detail the sealing test method of using the pressure detection component 144 to detect whether the downstream pressure has dropped, through the high-pressure introduction component to realize the pressure introduction operation of the sealing test of multiple check valves at the same time. , including the following steps:

S1: Isolate the respective upstream and downstream pipelines of the first check valve 10 , the second check valve 20 , the third check valve 30 and the fourth check valve 40 ;

S2: Open the first valve 610a, release the high pressure of the primary circuit waste heat discharge system 700 of the nuclear power plant, lead it to the second valve assembly 620 through the first branch 621 of the high pressure hose, and introduce the high pressure through the fourth valve 620d to adjust the high pressure The test pressure to the first check valve 10 and the third check valve 30 is then introduced to the downstream pipeline of the first check valve 10 and the third check valve 30;

Lead to the third valve assembly 630 through the second branch 631 of the high-pressure hose, the high pressure is adjusted to the test pressure of the second check valve 20 and the fourth check valve 40 through the sixth valve 630d, and then Introduced into the downstream pipeline of the second check valve 10 and the fourth check valve 40;

After the pressure induction is completed, the first valve 610a is closed to isolate the pipelines downstream of the first to fourth check valves.

S3: Release the upstream pipeline pressure of the first to fourth check valves, and detect pressure changes on the downstream pipelines of the first to fourth check valves through the pressure detection component 140 .

S4: Judging whether there is leakage according to the pressure change state, if the detected actual pressure is less than the test pressure, the downstream pipeline pressure decreases, and it is judged that one or more of the first to fourth check valves has leakage.

It can be understood that if the pressure detecting member 144 detects no pressure change on the downstream pipelines of the first to fourth check valves, and the downstream pipeline pressure remains stable, it is determined that the first to fourth check valves The sealing test is all qualified, which can save a lot of test time; if the pressure detection part 144 detects pressure changes on the downstream pipelines of the first to fourth check valves, and the downstream pipeline pressure decreases, it can only be judged that the One or more check valves among the first to fourth check valves are leaking, and it is necessary to arrange further sealing tests to confirm which check valve is leaking.

To sum up, the present invention provides a nuclear power plant check valve test device and test method. The pressure induction operation is realized through the high-pressure hose, so that there is no need to start the low-pressure safety injection pump, which improves the test efficiency and greatly reduces the low-pressure safety injection pump. There are multiple risks such as equipment damage and personal injury when the injection pump is started; the pressure detection device is used to detect the pipeline pressure during the check valve test process, realizing multiple functions at one end, which greatly reduces the test cost investment, and the pressure gauge is connected through a high-pressure hose. The pressure gauge can be installed in a position that is more favorable for reading, and the flexibility is extremely high, thereby reducing the reading error; meanwhile, the test method for the check valve provided by the invention makes the test work simpler and greatly improves the test efficiency.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of the claims of the present invention.

Claims (13)

1. A nuclear power plant check valve test device, used for the safety injection pipeline check valve sealing test, including: Upstream pipeline (101) for connection to the safety injection system (100); Downstream piping (102) for connecting to the reactor coolant system (500); The first check valve (10), connected between the upstream pipeline (101) and the downstream pipeline (102), is characterized in that it also includes: The high-pressure introduction assembly is connected between the waste heat discharge system (700) of the primary circuit and the downstream pipeline (102) of the first check valve (10), and is used to introduce the pressure of the waste heat discharge system of the primary circuit from high pressure and reducing the high pressure to the test pressure of the first check valve (10) and delivering it to the pipeline (120) downstream of the first check valve (10); A pressure detection piece (130), connected to the downstream pipeline (102) or upstream pipeline (101) of the first check valve (10), used to detect the test pressure of the first check valve (10) and During the sealing test process of the first check valve (10), the pressure change of the downstream pipeline (102) or the upstream pipeline (101) of the first check valve (10) is detected. 2. The check valve test device according to claim 1, characterized in that, the condition of introducing high pressure is: before the sealing test is carried out to the first check valve (10), cut off the upstream pipeline (101) respectively Connection to safety injection system (100) and downstream line (102) to reactor coolant system (500). 3. The check valve test device according to claim 1, characterized in that, the high-pressure introduction assembly comprises a high-pressure hose (600) and a first valve assembly ( 610) and a second valve assembly (620); One end of the high-pressure introduction assembly is connected to the main line (611) of the primary circuit waste heat discharge system through a first valve assembly (610), and the other end is connected to the first check valve (10) through a second valve assembly (620). ) on the downstream line (102), the second valve assembly (620) is used to release the high pressure to the test pressure of the first check valve (10) and introduce it to the first check valve ( 10) Downstream line (102). 4. The check valve test device according to claim 3, characterized in that, the pressure detection part (130) comprises: A pressure detection female head assembly (131), connected to the upstream pipeline (101) of the first check valve (10); A pressure detection sub-head assembly (132), pluggably connected to the female head assembly (131), used to detect the test pressure of the first check valve (10) and to detect the test pressure of the first check valve (10). 10) During the sealing test, the pressure change of the upstream pipeline (101) of the first check valve is detected. If the detected actual pressure is greater than the test pressure and the upstream pressure increases, it is judged that the check valve is leaking. 5. The check valve test device according to claim 3, characterized in that, the pressure detection part (130) comprises: A pressure detection female head assembly (131), connected to the downstream pipeline (102) of the first check valve (10); A pressure detection sub-head assembly (132), pluggably connected to the female head assembly (131), used to detect the test pressure of the first check valve (10) and to detect the test pressure of the first check valve (10). 10) During the tightness test, detect the pressure change of the downstream pipeline (102) of the first check valve (10), if the actual pressure detected is less than the test pressure, when the downstream pressure decreases, it is judged that the check valve has leakage . 6. The check valve test device according to claim 3, characterized in that, the other end of the high-pressure hose (600) is also connected to a pressure detection piece (144), and the pressure detection piece (144) passes through the first The second valve assembly (620) is connected to the downstream pipeline of the first check valve (10) and the third check valve (30), and the pressure detecting element (144) is connected to the second check valve assembly (630) through the third valve assembly (630). On the pipeline downstream of the check valve (20) and the fourth check valve (40). 7. The check valve test device according to claim 4 or 5, characterized in that, the female head assembly (131) of the pressure detection piece comprises: A connection female (135a), one end of the connection female (135a) is connected to a flange (140), and the flange (140) is connected to a fifth valve (141), and the fifth valve (141) is connected to an upstream pipeline (101) or downstream line (102) for opening or closing line pressure; The pressure detection sub-head assembly (132) includes: A connection subhead (135b), one end of the connection subhead (135b) is movably connected to the other end of the connection female head (135a); The other end of the connection subhead (135b) is connected to a pressure gauge (138) through a first joint (137), and the pressure gauge (138) is used to detect the actual pressure. 8. The check valve test device according to claim 7, characterized in that, the other end of the connecting subhead (135b) is also connected with a second joint (136), and the second joint (136) is used for Connect the manual shut-off valve (139), and the manual shut-off valve (139) is connected with the drain exhaust pipe (133) for controlling pipeline pressure relief; The first connector (137) includes a first female connector (137a) and a first sub connector (137b) that is pluggably connected to the first female connector (137a); The second connector (136) includes a second female connector (136a) and a second sub-connector (136b) detachably connected to the second female connector (136a); The connecting female head (135a) is automatically closed in an empty state; The pressure gauge (138) is connected to the first joint (137) through an instrument high-pressure hose (134), which is used to place the pressure gauge (138) at a position easy to read. 9. The check valve test device according to claim 6, characterized in that, the other end of the high-pressure hose (600) is divided into a first branch (621) and a second branch (631), the The other end of the first branch (621) is connected to the second valve assembly (620), and the other end of the second valve assembly (620) is connected to the downstream pipeline (102) of the first check valve (10) ; The other end of the second branch (631) is connected to the third valve assembly (630), and the other end of the third valve assembly (630) is connected to the second check valve (20) and the fourth check valve (40) on the downstream pipeline. 10. The check valve test device according to claim 3, characterized in that, the high-pressure hose (600) adopts a high-pressure hose black rubber hose for temporary pressure introduction; the high-pressure hose (600) and the first A valve assembly (610), the second valve assembly (620) and the third valve assembly (630) are connected by a slip joint (800) of the same structure; the slip joint (800) is equipped with a high pressure A gasket (801), the high-pressure gasket (801) is used for sealing after compression. 11. The check valve test device according to claim 6, characterized in that, the first valve assembly (610) comprises a flange (610b) and a first valve (610a) connected to the flange (610b), The first valve (610a) is used to open or close the pipeline; The second valve assembly (620) includes: a flange (620a), a second valve (620b) connected to the flange (620a), a third valve (620c) connected to the second valve (620b) ), and a fourth valve (620d) connected between the second valve (620b) and the third valve (620c); Both the second valve (620b) and the third valve (620c) are used to open or close the pipeline, and the fourth valve (620d) is used to control pipeline pressure relief, reducing the introduced high pressure to the first reverse Test pressure required for stop valve (10). 12. A nuclear power plant check valve test method, used for nuclear power plant safety injection pipeline check valve sealing test, is characterized in that, comprising the following steps: S1: Drain the high pressure of the primary circuit waste heat discharge system (700) of the nuclear power plant to the test pressure and introduce it to the downstream pipeline (102) of the check valve; S2: Detect the test pressure of the downstream pipeline (102) or upstream pipeline (101) of the first check valve (10) through a movably connected pressure detection member (130); S3: Detect the pressure change of the upstream or downstream pipeline of the first check valve (10) during the test, judge whether the first check valve (10) leaks according to the pressure change state, if the downstream pipeline (102) detects If the actual pressure is lower than the test pressure and the downstream pressure decreases, or the actual pressure detected by the upstream pipeline (101) is greater than the test pressure and the upstream pressure increases, it is determined that the first check valve (10) has leakage. 13. The check valve testing method according to claim 12, characterized in that, the pressure detecting member (144) is used to detect the first check valve (10), the second check valve (20), The downstream pipeline pressure of the third check valve (30) and the fourth check valve (40) changes, if the actual pressure detected is less than the test pressure, the downstream pressure decreases, and it is judged that the first check valve (10), One or more of the second check valve (20), the third check valve (30) and the fourth check valve (40) have leakage.