Valve detection and valve cavity flat pressing device

Abstract

The utility model relates to a valve detection and valve cavity flat pressing device, which relates to the field of valve maintenance and comprises a valve adapter, a first stop valve, a pressure gauge, a second stop valve and an air source adapter which are sequentially connected and communicated. The pressure gauge is connected between the first stop valve and the second stop valve. The beneficial effects of the utility model are that the valve adapter is connected with a pollution discharge nozzle or a discharge hole of a valve to be detected, the air source adapter is used for connecting an external air source, adjusting the opening and closing of the first stop valve and the second stop valve and the opening degree of the first stop valve, and observing the pressure in the device through the pressure gauge. The device can pressurize the interior of a valve cavity of a to-be-detected valve, inspect a sealing surface before the valve is installed, or test (inner leakage) whether a faulty valve is intact after maintenance, and also can flatly press the two sides (valve cavity) of the sealing surface when the valve is difficult to open due to large pressure difference between the two sides of the sealing surface, thereby realizing smooth opening of the valve.

Description

Technical Field

[0001] The utility model relates to the field of valve maintenance, in particular to a valve detection and valve cavity pressure leveling device. Background Art

[0002] Various types of valves are the main equipment in natural gas transmission stations. Valves are used to control the flow direction and on-off of gas in the stations. Valves include ball valves, plug valves, throttling stop valves, etc. Ball valves are widely used in natural gas stations because of their good sealing effect and simple structure.

[0003] The ball valve is sealed by sealing surfaces on both sides or one side to achieve on-off control of the pipeline. When the sealing surface of the ball valve is scratched or stuck, high-pressure gas leaks into the valve cavity from the tiny gap of the sealing surface, and leaks into the external environment from the sewage outlet during maintenance, causing fire and explosion accidents; or directly leaks into the downstream pipeline, causing uncontrollable process conditions, and there is a problem of internal leakage of the valve that cannot be predicted in advance. On the contrary, if the sealing surface is intact and the valve is in a closed state for a long time, due to equipment inspection or other reasons, the gas in the valve cavity is released to zero state. At this time, there is a large pressure difference on both sides of the valve sealing surface, and the valve cannot be opened normally due to the double piston effect.

[0004] The existing detection device is not suitable for the internal leakage detection of the in-service ball valve, and cannot solve the situation that the valve cannot be opened due to the pressure difference. Utility Model Content

[0005] The technical problem to be solved by the utility model is how to perform internal leakage detection on valves before commissioning and on-line.

[0006] The utility model provides a technical solution to the above-mentioned technical problems as follows: a valve detection and valve cavity pressure equalization device, comprising a valve adapter, a first stop valve, a pressure gauge, a second stop valve and an air source adapter, wherein the valve adapter, the first stop valve, the second stop valve and the air source adapter are connected and communicated in sequence, and the pressure gauge is connected between the first stop valve and the second stop valve.

[0007] The beneficial effects of the utility model are as follows: the valve adapter is connected to the sewage discharge nozzle or the discharge hole of the valve to be tested, the air source adapter is used to connect the external air source, adjust the opening and closing of the first stop valve and the second stop valve, and the opening of the first stop valve, and observe the pressure in the device through the pressure gauge. It can realize the internal pressure filling of the valve cavity of the valve to be tested, check the sealing surface before installing the valve, or test whether the faulty valve (internal leakage) is intact after repair. It can also be used to pressurize both sides of the sealing surface (valve cavity) when the valve is difficult to open due to the large pressure difference on both sides of the sealing surface, so as to realize the smooth opening of the valve.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, there are at least two valve adapters, and the models of at least two valve adapters are different, and one of the valve adapters is connected to and communicated with the first stop valve.

[0010] The beneficial effect of adopting the above further solution is: at least two valve adapters of different models are provided, so that the valve detection and valve cavity pressure equalization device can be adapted to valves of different models to be detected, and has a wide range of applications.

[0011] Furthermore, it also includes a high-pressure elbow, and the valve adapter and the first stop valve are connected and communicated through the high-pressure elbow.

[0012] The beneficial effect of adopting the above further solution is: a high-pressure elbow with a bend is provided to facilitate the valve adapter and the sewage discharge nozzle or discharge hole at the bottom of the valve to be tested.

[0013] Furthermore, the valve adapter, the high-pressure elbow, the first stop valve and the second stop valve are all made of stainless steel.

[0014] The beneficial effect of adopting the above further solution is that the material is stainless steel, which prevents the valve detection and valve cavity pressure equalization device from rusting.

[0015] Furthermore, the first stop valve is a double-chamber stop valve.

[0016] Furthermore, the double-chamber stop valve has a pressure relief valve.

[0017] The beneficial effect of adopting the above further scheme is that after the valve detection and valve cavity pressure equalization device is used, the internal pressure is released through the pressure relief valve, and the device is restored to its original state, which facilitates the disassembly of the valve detection and valve cavity pressure equalization device.

[0018] Furthermore, the second stop valve is a high-pressure stop valve.

[0019] Furthermore, it also includes a high-pressure hose, and the second shut-off valve and the air source adapter are connected and communicated through the high-pressure hose.

[0020] Furthermore, it also includes an air source, and the air source adapter is connected and communicated with the air source.

[0021] Furthermore, the gas source is a nitrogen cylinder.

[0022] The beneficial effect of adopting the above further scheme is: using a nitrogen bottle containing nitrogen as a gas source, the portability is good, and the inert gas will not react with the substance in the valve to be tested, so the safety is high.

[0023] The valve detection and valve cavity pressure leveling device of this embodiment has the following beneficial effects:

[0024] 1. Improve valve detection methods and accurately determine the internal leakage of valves.

[0025] This device specifically solves the two problems of pre-commissioning inspection of spare valves and online valve internal leakage detection. Compared with the past empirical method of using audiometry, this device can record the pressure release volume and time, calculate the pressure release speed, and make a more accurate judgment on the valve internal leakage situation.

[0026] 2. Solve the problem of valve switching under abnormal working conditions.

[0027] This device connects to an external gas source and controls the pressure to achieve equal pressure between the inside of the valve cavity and the process pipeline, reduce the effect and influence of the double pistons on the ball valve sealing seat, and solve the problem of limited valve opening and closing under abnormal working conditions. This device fills the technical gap of valves that are difficult to open under abnormal working conditions, adopts reverse thinking, reduces the axial force on the valve ball, and facilitates operation by maintenance personnel.

[0028] 3. Unify component standards to prevent damage to the main equipment.

[0029] The device is connected to the valve to be tested through a valve adapter and installed reliably, meeting the standards and requirements of NPT and metric threads, achieving universal and interchangeable connection parts, ensuring matching and reliability of equipment connection, and preventing damage to the equipment body.

[0030] 4. Safe operation and reduced risks.

[0031] This device connects the sewage nozzle or discharge hole to the outside, and controls the discharge through the double-chamber stop valve. The gas discharge direction and speed are controllable, and the operation is safer. In addition, the various connectors of this device have been pressure tested and there are no safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the valve detection and valve cavity pressure leveling device of the utility model;

[0033] Figure 2 This is the principle diagram of the valve detection and valve cavity pressure leveling device of the utility model.

[0034] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0035] 1. Valve adapter; 2. High-pressure elbow; 3. First stop valve; 4. Second stop valve; 5. Pressure gauge; 6. High-pressure hose; 7. Air source adapter; 8. Air source; 9. Valve to be tested. DETAILED DESCRIPTION

[0036] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0037] like Figure 1 and Figure 2 As shown, this embodiment provides a valve detection and valve cavity pressure equalization device, including a valve adapter 1, a first stop valve 3, a pressure gauge 5, a second stop valve 4 and an air source adapter 7, the valve adapter 1, the first stop valve 3, the second stop valve 4 and the air source adapter 7 are connected and communicated in sequence, and the pressure gauge 5 is connected between the first stop valve 3 and the second stop valve 4.

[0038] The valve adapter 1 is connected to the sewage discharge nozzle or the discharge hole of the valve to be tested 9, and the air source adapter 7 is used to connect the external air source to adjust the opening and closing of the first stop valve 3 and the second stop valve 4, as well as the opening of the first stop valve 3, and the pressure in the device is observed through the pressure gauge 5. It can realize the internal pressure filling of the valve cavity of the valve to be tested 9, check the sealing surface before installing the valve, or test whether the faulty valve (internal leakage) is intact after repair. It can also be used to pressurize both sides of the sealing surface (valve cavity) when the valve is difficult to open due to the large pressure difference on both sides of the sealing surface, so as to realize the smooth opening of the valve.

[0039] Specifically, a three-way joint is connected between the first stop valve 3 and the second stop valve 4, and the pressure gauge 5 is connected to the three-way joint.

[0040] The specific steps are as follows:

[0041] 1. Dismantle the drain nozzle or discharge hole of the valve 9 to be tested:

[0042] Check the valve process status, confirm that the valve cavity is not pressurized, and remove the valve drain nozzle or bleed hole.

[0043] 2. Install the ball valve (valve to be tested 9) adapter:

[0044] Confirm whether the thread type and specifications of the valve adapter 1 are consistent with the drain nozzle or discharge hole of the ball valve, and install the valve adapter 1 tightly. To prevent leakage at the threaded connection, use an appropriate amount of polytetrafluoroethylene sealing tape.

[0045] 3. Install the remaining connectors:

[0046] Install and check the sealing gaskets between the connecting parts (valve adapter 1, first stop valve 3, pressure gauge 5, second stop valve 4 and air source adapter 7). Use polytetrafluoroethylene gaskets for the sealing gaskets. Tighten the two ends and install them. Connect the end of the air source adapter 7 to the external air source.

[0047] 4. Detection or troubleshooting:

[0048] In the first case, close the second stop valve 4, dynamically observe and detect the internal leakage of the valve, and record the changes in pressure, time and maintenance process.

[0049] In the second case, the second stop valve 4 is opened, the air source pressure is adjusted and controlled through the first stop valve 3, the pressure change in the valve cavity is detected, and the sealing state of the valve is determined.

[0050] In the third case, the second stop valve 4 is opened, and the valve cavity is adjusted and controlled to be consistent with the operating pressure (flat pressure) through the first stop valve 3 to cooperate with the valve action or maintenance.

[0051] 5. On-site recovery:

[0052] Close the gas source and the second stop valve 4, vent through the first stop valve 3, restore the equipment to its original state, disassemble the valve detection and valve cavity pressure equalization devices, and store them in the box for use.

[0053] On the basis of the above technical solution, there are at least two valve adapters 1 , and the models of at least two valve adapters 1 are different, and one of the valve adapters 1 is connected to and communicated with the first stop valve 3 .

[0054] At least two valve adapters 1 of different models are provided, so that the valve detection and valve cavity pressure equalization device can be adapted to different models of valves 9 to be detected, and has a wide range of applications.

[0055] On the basis of the above technical solution, it further comprises a high-pressure elbow 2 , through which the valve adapter 1 and the first stop valve 3 are connected and communicated.

[0056] A high-pressure elbow 2 is provided with a bend to facilitate the connection between the valve adapter 1 and the sewage discharge nozzle or discharge hole at the lower part of the valve 9 to be tested.

[0057] On the basis of the above technical solution, the valve adapter 1, the high-pressure elbow 2, the first stop valve 3 and the second stop valve 4 are all made of stainless steel.

[0058] The material is stainless steel to prevent the valve detection and valve cavity pressure equalization device from rusting.

[0059] On the basis of the above technical solution, the first stop valve 3 is a double-chamber stop valve.

[0060] On the basis of the above technical solution, the double-chamber stop valve has a pressure relief valve.

[0061] After the valve detection and valve cavity pressure-leveling device is used, the internal pressure is released through the pressure relief valve, and the device is restored to its original state, making it easy to disassemble the valve detection and valve cavity pressure-leveling device.

[0062] On the basis of the above technical solution, the second stop valve 4 is a high-pressure stop valve.

[0063] On the basis of the above technical solution, it further comprises a high-pressure hose 6 , through which the second shut-off valve 4 and the gas source adapter 7 are connected and communicated.

[0064] On the basis of the above technical solution, it further includes an air source 8 , and the air source adapter 7 is connected and communicated with the air source 8 .

[0065] On the basis of the above technical solution, the gas source 8 is a nitrogen cylinder.

[0066] A nitrogen cylinder containing nitrogen is selected as the gas source, which has good portability, and the inert gas will not react with the substance in the valve 9 to be tested, so it is highly safe.

[0067] Alternatively, the gas source 8 may also be a fixedly installed gas storage tank. In addition to nitrogen, the gas source 8 may also be other inert gases.

[0068] The valve detection and valve cavity pressure equalization device of this embodiment can be used for the detection of any valve. In this embodiment, a ball valve commonly used in a natural gas transmission station is taken as an example to introduce the working principle and usage of the device.

[0069] This device is mainly used for valve internal leakage detection and valve cavity flat pressure. It is suitable for detection before new valves are put into use or after faulty valves are repaired. In addition, this tool can be used to eliminate the problem of valve opening and closing difficulties caused by the valve cavity being emptied by flat pressure. It mainly solves the following three problems.

[0070] Before testing or troubleshooting the valve, connect the valve adapter 1 to the drain nozzle of the ball valve (valve to be tested 9), and connect the air source adapter 7 to the external air source or air source 8.

[0071] (1) The first case is valve internal leakage test. The working object is an online process valve. The valve may have internal leakage, but the degree of internal leakage cannot be accurately determined.

[0072] Close the second stop valve 4, close the pressure relief valve of the first stop valve 3, and without injecting gas source, visually detect the pressure value change and time in the valve cavity through the pressure gauge 5, and detect the internal leakage of the valve to be tested 9 by recording and statistically analyzing the pressure change data. After the maintenance personnel fill the sealing material to the ball valve sealing seat, they can read the data of the pressure gauge 5 through this device, and can visually see the internal pressure change, providing a technical reference for the maintenance personnel's operation.

[0073] (2) The second case is valve sealing detection. The working object is a non-online new valve or a repaired valve. This device is used to detect the valve sealing performance before the valve is installed and put into use, so as to timely discover hidden problems such as failure of the sealing valve seat due to equipment transportation collision, poor storage, etc.

[0074] Open the second stop valve 4, inject high-pressure gas into the valve to be tested 9, adjust and control the gas source pressure by adjusting the opening of the first stop valve 3, detect the pressure change in the valve cavity through the pressure gauge 5, and record the pressure attenuation change in the valve cavity under different pressure intensities. After data analysis, make a judgment on the sealing state of the valve to be tested 9, and provide reference and basis for subsequent valve installation, commissioning, maintenance and repair.

[0075] (3) The third case is switch failure handling.

[0076] The working object is to empty the valve cavity of the online valve and bear pressure on both sides or one side. The sealing form of the ball valve in the natural gas station mostly adopts a double-piston sealing valve seat. During the regular inspection and maintenance, the valve cavity is emptied to judge and detect the technical status of the valve. After the valve cavity is emptied, the force area of ​​the sealing valve seat in the pipeline direction increases, and the axial force of the sealing valve seat pushing the valve ball under the action of the double pistons increases. For valves with a nominal diameter greater than 12 inches, it is difficult to open them simply by relying on the force of the operator, especially when the valve seat is subjected to force in both directions, resulting in obvious problems of switching restrictions. In addition, due to the excessive opening torque, if force-increasing measures are taken, it may cause excessive wear of the valve body transmission parts, ball, sealing valve seat, etc., and serious failures may occur in severe cases.

[0077] Open the second stop valve 4 and inject high-pressure gas into the valve cavity of the valve to be tested 9. Adjust and control the gas injection pressure by adjusting the opening of the first stop valve 3 so that the gas pressure in the valve cavity is close to or equal to the pipeline pressure, thereby reducing the axial force of the sealing valve seat. During this period, the maintenance personnel switch the movable valve to achieve normal opening of the valve to be tested 9.

[0078] In one specific example, the model and material of the valve detection and valve cavity pressure equalization device are as follows:

[0079]

[0080]

[0081] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0082] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A valve detection and valve cavity pressure equalization device, characterized in that: The invention comprises a valve adapter (1), a first stop valve (3), a pressure gauge (5), a second stop valve (4) and an air source adapter (7); the valve adapter (1), the first stop valve (3), the second stop valve (4) and the air source adapter (7) are connected and communicated in sequence; the pressure gauge (5) is connected between the first stop valve (3) and the second stop valve (4).

2. A valve detection and valve cavity pressure leveling device according to claim 1, characterized in that: There are at least two valve adapters (1), and the models of at least two valve adapters (1) are different. One of the valve adapters (1) is connected to and communicates with the first stop valve (3).

3. A valve detection and valve cavity pressure leveling device according to claim 1, characterized in that: It also comprises a high-pressure elbow (2), and the valve adapter (1) and the first stop valve (3) are connected and communicated through the high-pressure elbow (2).

4. A valve detection and valve cavity pressure leveling device according to claim 3, characterized in that: The valve adapter (1), the high-pressure elbow (2), the first stop valve (3) and the second stop valve (4) are all made of stainless steel.

5. A valve detection and valve cavity pressure leveling device according to claim 1, characterized in that: The first stop valve (3) is a double-chamber stop valve.

6. A valve detection and valve cavity pressure leveling device according to claim 5, characterized in that: The double-chamber stop valve has a pressure relief valve.

7. A valve detection and valve cavity pressure leveling device according to claim 1, characterized in that: The second stop valve (4) is a high-pressure stop valve.

8. A valve detection and valve cavity pressure leveling device according to claim 1, characterized in that: It also comprises a high-pressure hose (6), and the second stop valve (4) and the gas source adapter (7) are connected and communicated through the high-pressure hose (6).

9. A valve detection and valve cavity pressure equalization device according to any one of claims 1 to 8, characterized in that: It also includes an air source (8), and the air source adapter (7) is connected to and communicates with the air source (8).

10. A valve detection and valve cavity pressure leveling device according to claim 9, characterized in that: The gas source (8) is a nitrogen bottle.

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