CN213452366U

CN213452366U - Pressure test plug

Info

Publication number: CN213452366U
Application number: CN202022347829.2U
Authority: CN
Inventors: 俞渊; 沈裕; 许志泉; 龚伟; 吴强; 吴诚忠; 张莉; 曹晶; 张艳
Original assignee: China International Marine Containers Group Co Ltd; Zhangjiagang CIMC Sanctum Cryogenic Equipment Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd
Current assignee: China International Marine Containers Group Co Ltd; Zhangjiagang CIMC Sanctum Cryogenic Equipment Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2021-06-15
Anticipated expiration: 2030-10-20

Abstract

The utility model provides a pressure test plug, which comprises a plug main body and a first sealing ring; the outer periphery of the front end of the plug main body is provided with an external thread to form a connecting section for being in threaded connection with an external interface; the plug main body is provided with a first air chamber and a second air chamber; the periphery of the connecting section is located to first sealing washer cover to the opening of sealed second air chamber. When the pressure of the gas supply system is detected, gas in the external interface pushes the first sealing ring to deform so as to seal the external interface. After pressure detection is completed, gas pressure in the external interface is released, so that the gas pressure on the first sealing ring is removed, and the pressure of the first sealing ring on the external interface is reduced, so that the pressure testing plug can be conveniently moved out. Utilize the pressure of external interface itself to make first sealing washer take place to warp under the inside gas pressure effect of external interface to sealed external interface, first sealing washer can not produce impurity and block up external interface, can effectually avoid causing the influence to external interface.

Description

Pressure test plug

Technical Field

The utility model relates to a sealed frock technical field, in particular to pressure testing end cap.

Background

In the field of liquefied natural gas supply, in the process of manufacturing a gas supply system, the tank body and a corresponding pipeline need to be subjected to tightness and pressure detection so as to ensure the gas tightness of the gas supply system and enable the gas supply system to be used normally. Therefore, in the manufacturing process of the gas supply system, corresponding plug tools are required to plug the interfaces, and then the gas supply system is pressurized to supply gas so as to detect the tightness of the gas supply system.

In the prior art, a plug tool is generally connected in an interface in a threaded connection mode, in order to plug and seal the interface, sealing materials such as raw material belts or sealing glue are wound on threads of the plug tool to ensure sealing, but the sealing materials such as the sealing glue are easy to generate impurities when being used, so that parts such as a valve are plugged, and the quality of the interface is affected.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a pressure testing end cap can effectually avoid causing the influence to the interface.

In order to solve the technical problem, the utility model adopts the following technical scheme:

according to one aspect of the utility model, the utility model provides a pressure test plug, which is characterized in that the pressure test plug comprises a plug main body and a first sealing ring; the outer periphery of the front end of the plug main body is provided with an external thread to form a connecting section for being in threaded connection with an external interface; the plug main body is provided with a first air chamber and a second air chamber; the first air chamber is opened at the front end of the connecting section and can be communicated with the inner space of the external interface; the front end of the second air chamber is opened, and the second air chamber is communicated with the first air chamber; the first sealing ring has elasticity; the first sealing ring is sleeved on the periphery of the connecting section and seals the opening of the second air chamber; the gas in the external interface can press the first sealing ring at the opening of the second air chamber through the first air chamber and the second air chamber, so that the first sealing ring is elastically deformed to seal the external interface.

In some embodiments, the plug body further includes a limiting section connected to the rear end of the connecting section, and an annular casing sleeved on the periphery of the limiting section, and the second air chamber is formed by the annular casing and the limiting section.

In some embodiments, the limiting section extends beyond the connecting section radially outwards at the joint of the limiting section and the connecting section to form a first step; the first step has a space in the radial direction from the annular housing to form an opening of the second air chamber; the first seal ring is abutted against the first step and the annular shell along the axial direction.

In some embodiments, the annular housing is sleeved on the periphery of the position limiting section, so that the position limiting section can rotate relative to the annular housing; one end of the annular shell, which is far away from the first sealing ring, is connected with the limiting section in a sealing manner.

In some embodiments, a second sealing ring is arranged between the limiting section and the annular shell, and the second sealing ring has elasticity; the second sealing ring is sleeved on the periphery of the limiting section in the second air chamber and is abutted against the annular shell, and the second sealing ring is in interference fit with the limiting section and the annular shell.

In some embodiments, the limiting section is provided with a ring groove which is opened radially outwards, and the second sealing ring is clamped and limited in the ring groove.

In some embodiments, the pressure testing plug further comprises a sealing gasket, wherein the sealing gasket has elasticity; the sealing gasket is clamped and sleeved in the annular groove; the sealing gasket is abutted against the inner wall of the annular shell and is in interference fit with the annular shell.

In some embodiments, one surface of the sealing gasket is attached to one axial side of the second sealing ring, and the other surface of the sealing gasket abuts against the side wall of the annular groove.

In some embodiments, an outer peripheral wall of one end of the limiting section, which faces away from the connecting section, is provided with anti-slip insections.

In some embodiments, the limiting section is provided with an air hole communicating the first air chamber and the second air chamber.

According to the above technical scheme, the utility model discloses following advantage and positive effect have at least:

in the utility model, the outer periphery of the front end of the plug main body is provided with an external thread to form a connecting section for connecting with an external interface thread; the plug main body is provided with a first air chamber and a second air chamber; the first sealing ring is sleeved on the periphery of the connecting section and seals the opening of the second air chamber; the gas in the external interface can extrude the first sealing ring at the opening of the second air chamber through the first air chamber and the second air chamber, so that the first sealing ring is elastically deformed to seal the external interface. When the pressure of the gas supply system is detected, gas in the external interface is conveyed to the second gas chamber through the first gas chamber, so that the first sealing ring is pushed to deform, the first sealing ring is tightly pressed on the port of the external interface, and the external interface is sealed. After the pressure detection of the gas supply system is completed, the gas pressure in the external interface is released, so that the gas pressure on the first sealing ring is removed, and the pressure of the first sealing ring on the external interface is reduced, so that the pressure testing plug can be conveniently moved out. Utilize the pressure of external interface itself to make first sealing washer take place to warp under the inside gas pressure effect of external interface to sealed external interface, first sealing washer can not produce impurity and block up external interface, can not lead to the fact the influence to external interface, can effectually avoid causing the influence to external interface.

Drawings

Fig. 1 is the structural schematic diagram of the pressure testing plug of the present invention.

Fig. 2 is the sectional structure schematic diagram of the pressure testing plug of the embodiment of the utility model.

Fig. 3 is a schematic structural view of the plug body according to the embodiment of the pressure testing plug of the present invention, wherein the annular casing is not shown.

Fig. 4 is a schematic structural view of the annular casing according to the embodiment of the pressure testing plug of the present invention.

The reference numerals are explained below:

100. a plug main body; 110. a connecting section; 120. a limiting section; 121. a first step; 122. a second step; 130. an annular housing; 140. a first air chamber; 150. a second air chamber; 160. air holes; 170. a ring groove; 200. a first seal ring; 300. a second seal ring; 400. and a gasket.

Detailed Description

Exemplary embodiments that embody features and advantages of the present invention will be described in detail in the following description. It is to be understood that the invention is capable of other and different embodiments and its several details are capable of modification without departing from the scope of the invention, and that the description and drawings are to be regarded as illustrative in nature and not as restrictive.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Fig. 1 is the structural schematic diagram of the pressure testing plug of the present invention. Fig. 2 is the sectional structure schematic diagram of the pressure testing plug of the embodiment of the utility model.

Referring to fig. 1 and 2, the present embodiment provides a pressure testing plug for sealing an interface of a pressure device or a gas supply system, so that gas can be filled into the pressure device or the gas supply system to detect the tightness of the pressure device or the gas supply system.

The pressure testing plug comprises a plug main body 100, a first sealing ring 200 and a second sealing ring 300. The front end of the plug main body 100 is provided with an external thread which can be connected with an external interface thread, and after the plug main body 100 is connected with the external interface thread, the first sealing ring 200 can elastically deform under the action of the pneumatic pressure of the external interface to seal the external interface.

Referring to fig. 2 and 3, in the present embodiment, the plug body 100 includes a connection section 110 located at the front end of the plug body 100 and having an external thread on the outer circumference, a limiting section 120 connected to the rear end of the connection section 110, and an annular housing 130 sleeved on the outer circumference of the limiting section 120.

The plug body 100 is provided with a first air chamber 140 and a second air chamber 150 which are communicated with each other. In this embodiment, the connecting section 110 and the limiting section 120 are hollow to form a first air chamber 140, and the first air chamber 140 is open at the front end of the connecting section 110 and can communicate with the internal space of the external interface, so that when the pressure device or the air supply system is inflated and pressurized, air can enter the second air chamber 150 through the first air chamber 140.

In this embodiment, the peripheral wall of the first air chamber 140 is cylindrical, and the axis thereof coincides with the axis of the connecting section 110, so as to facilitate the processing and ensure the stress balance at all positions in the circumferential direction of the connecting section 110.

A second air chamber 150 with an open front end is enclosed between the limiting section 120 of the plug body 100 and the annular shell 130.

The stopper body 100 has an air hole 160 formed on the stopper section 120 to communicate the first air chamber 140 and the second air chamber 150. In the actual design process, the size of the gas hole 160 is adjustable, so that the gas pressure in the second gas chamber 150 can be controlled.

Referring to fig. 3 again, in the present embodiment, the outer circumference of the connecting section 110 is a tapered thread, and the inner circumference of the corresponding external interface is provided with a corresponding tapered thread, so as to facilitate the alignment connection between the connecting section 110 and the external interface and initially seal the external interface.

In some embodiments, the outer circumference of the connecting section 110 does not have a taper. The thread on the outer circumference of the connection section 110 is a straight thread.

The limiting section 120 radially and outwardly extends beyond the connecting section 110 at the connection position with the connecting section 110 to form a first step 121, and the first sealing ring 200 is sleeved on the outer periphery of the connecting section 110 and axially abuts against the first step 121, so that the axial rearward movement of the first sealing ring 200 is limited.

In this embodiment, the limiting section 120 is provided with a ring groove 170 opening radially outward for limiting the second seal ring 300.

In this embodiment, the outer periphery of the limiting section 120 is further provided with a second step 122, the side wall of the second step 122 faces the connecting section 110, and the second step 122 is located on one side of the ring groove 170 facing away from the connecting section 110. After the annular housing 130 is sleeved on the limiting section 120, the sidewall of the second step 122 can limit the movement of the annular housing 130 in the axial direction.

The second step 122 extends radially outward beyond the ring groove 170. The bottom surface of the second step 122 is a conical surface or a cylindrical surface, so that the annular housing 130 can move from the connecting section 110 toward the limiting section 120 along the axial direction and is sleeved on the outer periphery of the limiting section 120.

The outer peripheral wall of the end of the limiting section 120 departing from the connecting section 110 is provided with anti-slip insections (not marked in the figure). Due to the design of the anti-slip insections, the plug main body 100 can be directly screwed by hand to rotate, so that the pressure test plug and an external interface can be quickly connected and detached. The hand is twisted and rotated without using tools, the connection and the disassembly are convenient, and the operation is simple.

Referring to fig. 2 and 4, in the present embodiment, the annular housing 130 has a structure with two open ends and a hollow interior, so as to be able to be sleeved on the outer circumference of the limiting section 120. The annular housing 130 includes a first section and a second section connected to a front end of the first section in the axial direction.

The inner peripheral wall of the first section of the annular housing 130 is a cylindrical structure so as to be fitted with the second step 122 of the limiting section 120, and the end of the first section of the annular housing 130 can be limited by the peripheral wall of the second step 122.

The inner circumferential wall of the second section of the annular housing 130 extends radially inwardly beyond the inner circumferential wall of the first section. There is a space between the inner peripheral wall of the second segment of the annular housing 130 and the corresponding position of the stopper segment 120, so that an opening of the second air chamber 150 is formed between the end of the second segment of the annular housing 130 and the stopper segment 120.

The annular housing 130 protrudes forward in the axial direction to the connection section 110, and a notch is formed inside the front end of the annular housing 130.

The end of the annular housing 130 facing away from the first sealing ring 200 is sealingly connected to the stopper section 120. The annular housing 130 is sleeved on the outer periphery of the position-limiting section 120, so that the position-limiting section 120 can rotate relative to the annular housing 130.

The inner peripheral wall of the end of the annular housing 130, which is away from the first sealing ring 200, is sleeved on the bottom wall of the second step 122 in an overlapping manner, a certain gap is formed between the end of the annular housing 130, which is away from the first sealing ring 200, and the side wall of the second step 122, so that the movement of the annular housing 130, which is backward along the axial direction, can be limited by the side wall of the second step 122, and due to the existence of the gap, when the annular housing 130 and the limiting section 120 move relatively, the friction force between the annular housing 130 and the limiting section 120 is reduced, so that the limiting section rotates.

In some embodiments, an axial thrust bearing is provided between the end of the annular housing 130 facing away from the end of the first seal ring 200 and the side wall of the second step 122.

The shape of the inner peripheral wall of the annular shell, the shape of the limiting section 120 and the shape of the connecting section 110 are convenient for quick assembly of the pressure test plug, and the assembly is simple.

Referring to fig. 2 again, the first sealing ring 200 is sleeved on the outer circumference of the connecting section 110 of the plug body 100 and seals the opening of the second air chamber 150. The first seal ring 200 has elasticity so as to be elastically deformable by pressure.

In this embodiment, the first seal ring 200 seals off the opening of the second plenum 150 and extends at least partially forward beyond the annular housing 130 such that after the connection segment 110 is connected to the external port, the first seal ring 200 can be connected to the end of the external port to seal the end of the external port.

After the plug body 100 is connected to the external interface and the gas supply system is inflated and pressurized, the gas in the external interface can press the first sealing ring 200 at the opening of the second gas chamber 150 through the first gas chamber 140 and the second gas chamber 150, and the obtained first sealing ring 200 is elastically deformed to seal the external interface.

The first sealing ring 200 is located at one end of the connecting section 110 facing the limiting section 120, and abuts against the first step 121 and the annular housing 130 along the axial direction to seal the opening of the second air chamber 150.

The first sealing ring 200 abuts against the first step 121, so that the axial rearward movement of the first sealing ring 200 is limited, to ensure that the first sealing ring 200 does not move axially rearward when the connecting section 110 is connected and fixed to the external port, thereby ensuring that the first sealing ring is blocked at the end of the external port.

In this embodiment, the first seal ring 200 is partially disposed in a gap in the inner periphery of the front end of the annular housing 130. The first seal ring 200 is radially clamped between the annular housing 130 and the connecting section 110, so that one axial side and the radial outer side of the first seal ring 200 are both attached to the annular housing 130, so as to have a better sealing effect on the second air chamber 150, and the gas in the second air chamber 150 can be effectively prevented from rushing out from between the first seal ring 200 and the annular housing 130.

In this embodiment, the notch of the annular housing 130 is rectangular, and in some embodiments, the peripheral wall of the notch of the annular housing 130 is circular arc.

In this embodiment, the first sealing ring 200 has a circular cross section, and partially seals the opening of the second air chamber 150 and partially protrudes from the opening of the second air chamber 150 for sealing the external interface.

In some embodiments, the cross-section of the first sealing ring 200 may be other structures, such as the cross-section of the second sealing ring is rectangular, or the cross-section of the second sealing ring may be divided into two parts, wherein the two parts are different structures, one part is used for sealing the opening of the second air chamber 150, and the other part extends out of the second air chamber 150 for sealing the external interface.

In some embodiments, a corresponding step or notch is provided on the inner side of the end of the outer port such that the first seal ring 200 fits against the corresponding step or notch, facilitating the first seal ring 200 to seal the outer port.

Meanwhile, in the process that the plug body 100 is connected to the external port, the first sealing ring 200 can be elastically deformed to a certain extent by the first step 123 and the external port, so as to seal the external port.

Referring again to fig. 2, a second seal ring 300 is disposed between the spacing segment 120 and the annular housing 130 and at an end of the annular housing 130 facing away from the first seal ring 200, sealing the annular housing 130 and the spacing segment 120.

The second sealing ring 300 has elasticity, the second sealing ring 300 is sleeved on the periphery of the limiting section 120 in the second air chamber 150 and abuts against the annular housing 130, and the second sealing ring 300, the limiting section 120 and the annular housing 130 are in interference fit, so as to seal one end of the annular housing 130.

The sealing of the second sealing ring 300 keeps the spacing segment 120 sealed all the time when rotating relative to the annular housing 130.

In this embodiment, the sealing ring 300 is engaged and retained in the ring groove 170 to prevent the sealing ring 300 from moving under the gas pressure of the second gas chamber 150 or under the force of the ring housing 130.

Referring to fig. 2 again, in the present embodiment, the pressure testing plug further includes a sealing gasket 400, and the sealing gasket 400 has an annular structure. The sealing pad 400 is clamped and sleeved in the ring groove 170; the sealing gasket 400 abuts against the inner wall of the annular housing 130 and is in interference fit with the annular housing 130. The cooperation of the sealing gasket 400 and the second sealing ring 300 forms two seals to the end of the annular housing 130 away from the first sealing ring 200, increasing the sealing effect.

In this embodiment, one sealing gasket 400 and one sealing gasket 300 are provided, and in some embodiments, the sealing gasket 400 and the second sealing gasket 300 may be provided in plurality or provided in plurality separately, so as to increase the sealing effect.

In this embodiment, one surface of the gasket 400 is attached to one axial side of the second seal ring 300, and the other surface is abutted against the side wall of the ring groove 170. The second sealing ring 300 and the sealing gasket 400 are fixed and positioned by the ring groove 170, so that the second sealing ring 300 and the sealing gasket 400 are prevented from moving, more effective sealing is realized, and meanwhile, the second sealing ring 300 and the sealing gasket 400 can be prevented from sliding to block the air hole 160.

The sealing gasket 400 abuts against the side wall of the ring groove 170, so that the sealing gasket 400 can be effectively prevented from falling along the axial direction, the deformation direction of the sealing gasket 400 is enabled to be along the radial direction, the tightness of connection between the sealing gasket 400 and the annular shell 130 is ensured, and the sealing effect is ensured.

The second sealing ring 300 and the sealing gasket 400 are arranged in the same annular groove 170, so that the second sealing ring 300 and the sealing gasket 400 can be mutually extruded to generate elastic deformation, the inner wall of the annular shell 130 is attached more tightly, and the sealing effect is enhanced.

In this embodiment, the plug body 100 has an external thread formed on the outer circumference of the front end thereof to form a connection section 110 for connecting with an external interface thread; the plug body 100 is provided with a first air chamber 140 and a second air chamber 150; the first sealing ring 200 is sleeved on the periphery of the connection section 110 and seals the opening of the second air chamber 150; gas in the external interface can press the first sealing ring 200 at the opening of the second gas chamber 150 through the first and

second gas chambers

140 and 150, so that the first sealing ring 200 is elastically deformed to seal the external interface. When the pressure of the gas supply system is detected, the gas in the external interface is delivered to the second gas chamber 150 through the first gas chamber 140, so that the first sealing ring 200 is pushed to deform, and the first sealing ring 200 is tightly pressed on the port of the external interface, so as to ensure the sealing of the external interface.

After the pressure detection of the gas supply system is completed, the gas pressure in the external interface is released, so that the gas pressure on the first sealing ring 200 is removed, and the pressure of the first sealing ring 200 on the external interface is reduced, so that the pressure testing plug can be conveniently removed. Utilize the pressure of external interface itself to make first sealing washer 200 take place to warp under the inside gas pressure effect of external interface to sealed external interface, first sealing washer 200 can not produce impurity and block up external interface, can not lead to the fact the influence to external interface, can effectually avoid causing the influence to external interface.

The annular housing 130 is sleeved on the outer periphery of the limiting section 120, so that the limiting section 120 can rotate relative to the annular housing 130, and the connecting section 110 is driven to rotate relative to the annular housing 130. After the air supply system is sealed, when the limiting section 120 is screwed to drive the connecting section 110 to rotate, because the front end of the annular shell 130 may contact the end of the external interface, the limiting section 120 can rotate relative to the annular shell 130, the rotation of the limiting section 120 does not need to overcome the friction between the annular shell 130 and the external interface, and the limiting section 120 is easier to rotate and saves labor.

In another embodiment of the pressure testing plug:

the pressure testing plug comprises a plug main body 100 and a first sealing ring 200. The plug body 100 includes a connection section 110 located at the front end of the plug body 100 and provided with external threads on the periphery, a limiting section 120 connected to the rear end of the connection section 110, and an annular housing 130 arranged on the periphery of the limiting section 120.

The end of the annular housing 130 facing away from the connecting section 110 is connected to the stopper section 120, and the annular housing 130 and the stopper section 120 are integrally formed or fixed together.

And an annular housing 130 sleeved on the periphery of the limiting section 120.

The first sealing ring 200 is sleeved on the outer periphery of the connecting section 110 of the plug body 100 and seals the opening of the second air chamber 150. The structure and position of the first sealing ring 200 refer to the position and structure of the above embodiments, and are not described in detail herein.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. A pressure testing plug is characterized by comprising:

the plug comprises a plug main body, a plug body and a plug body, wherein the periphery of the front end of the plug main body is provided with an external thread to form a connecting section for being in threaded connection with an external interface; the plug main body is provided with a first air chamber and a second air chamber; the first air chamber is opened at the front end of the connecting section and can be communicated with the inner space of the external interface; the front end of the second air chamber is opened, and the second air chamber is communicated with the first air chamber;

a first seal ring having elasticity; the first sealing ring is sleeved on the periphery of the connecting section and seals the opening of the second air chamber; the gas in the external interface can press the first sealing ring at the opening of the second air chamber through the first air chamber and the second air chamber, so that the first sealing ring is elastically deformed to seal the external interface.

2. The pressure test plug according to claim 1, wherein the plug body further comprises a limiting section connected to the rear end of the connecting section and an annular shell sleeved on the periphery of the limiting section, and the annular shell and the limiting section enclose to form the second air chamber.

3. The pressure test plug as claimed in claim 2, wherein the limiting section radially outwardly extends beyond the connecting section at the connection with the connecting section to form a first step; the first step has a space in the radial direction from the annular housing to form an opening of the second air chamber; the first seal ring is abutted against the first step and the annular shell along the axial direction.

4. The pressure test plug as claimed in claim 2, wherein the annular casing is sleeved on the periphery of the limiting section, so that the limiting section can rotate relative to the annular casing; one end of the annular shell, which is far away from the first sealing ring, is connected with the limiting section in a sealing manner.

5. The pressure test plug as claimed in claim 4, wherein a second sealing ring is arranged between the limiting section and the annular shell, and the second sealing ring has elasticity; the second sealing ring is sleeved on the periphery of the limiting section in the second air chamber and is abutted against the annular shell, and the second sealing ring is in interference fit with the limiting section and the annular shell.

6. The pressure test plug as claimed in claim 5, wherein the limiting section is provided with a ring groove which is opened radially outwards, and the second sealing ring is clamped and limited in the ring groove.

7. The pressure testing plug of claim 6, further comprising a sealing gasket, wherein the sealing gasket has elasticity; the sealing gasket is clamped and sleeved in the annular groove; the sealing gasket is abutted against the inner wall of the annular shell and is in interference fit with the annular shell.

8. The pressure testing plug according to claim 7, wherein one surface of the sealing gasket is attached to one axial side of the second sealing ring, and the other surface of the sealing gasket abuts against the side wall of the annular groove.

9. The pressure test plug according to claim 2, wherein the outer peripheral wall of the end of the limiting section, which is away from the connecting section, is provided with anti-slip insections.

10. The pressure test plug according to claim 2, wherein the limiting section is provided with an air hole for communicating the first air chamber and the second air chamber.