CN220396600U - Adjusting part and axial-flow type check valve - Google Patents

Abstract

The utility model discloses an adjusting assembly and an axial flow check valve, wherein the adjusting assembly comprises a supporting structure, a valve clack, an elastic piece and an adjusting piece, one end of the elastic piece is detachably connected with the adjusting piece, the other end of the elastic piece is suitable for being in limiting connection with the valve clack, and the adjusting piece is movably connected with the supporting structure. According to the utility model, the sliding pair formed between the first thread section and the second thread section enables the external force to act on the adjusting piece to slide close to or far away from the elastic piece so as to change the relative distance between the adjusting piece and the valve clack, and the elastic piece is in different compression lengths, so that different elastic pretightening forces can be configured for the pressures of different fluid media; the elastic members with different elastic coefficients can be replaced by detaching the adjusting members from the supporting structure. The utility model can flexibly adjust the non-return capacity of the configuration valve, is suitable for the use conditions of different fluid medium acting forces, and has good practicability.

Description

Adjusting part and axial-flow type check valve

Technical Field

The utility model relates to the technical field of coating processing and production, in particular to an adjusting component and an axial flow check valve.

Background

The axial flow check valve has the characteristics of low pressure drop, rapid opening and closing, timely dynamic response and low noise, is mainly used for the outlets of key equipment such as pumps, compressors and the like, and is widely applied to industries such as long-distance pipelines, petrochemical industry, storage facilities, LNG (liquefied natural gas) receiving stations and the like. In the liquefied natural gas industry, ultra-low temperature axial flow check valves are favored by users.

The check valve is displaced by the medium pressure acting on the flap to open the flow passage. At present, in the prior art, the check acting force of the check valve is usually set to a fixed value in the installation design stage, flexible adjustment cannot be performed, the check valve cannot adapt to the use working conditions of acting forces of different fluid media in practical application occasions, and practical requirements are difficult to meet.

Disclosure of Invention

The technical problem to be solved by the utility model is that in the related art, the check acting force of the check valve cannot be flexibly adjusted, the check valve cannot adapt to the use working conditions of acting forces of different fluid media in practical application occasions, and the defect that the practical requirement is difficult to meet exists.

The present utility model provides an adjustment assembly comprising:

the support structure is suitable for being fixedly arranged in the valve body;

the valve clack is movably arranged with the supporting structure;

the elastic piece is detachably connected with one end of the adjusting piece, the other end of the elastic piece is suitable for being connected with the valve clack in a limiting mode, the adjusting piece and the supporting structure are movably connected, a first threaded section is arranged on the supporting structure, a second threaded section is arranged on the adjusting piece, and the first threaded section and the second threaded section are correspondingly matched in a conformal mode and are configured to form a sliding pair;

under the action of external force, the adjusting piece is provided with an adjusting state of sliding close to or away from the valve clack relative to the supporting structure so as to configure the biasing force of the elastic piece on the valve clack.

Optionally, the adjusting member is provided with a flange portion, and in the adjusting state, the flange portion and the elastic member are in abutting fit; the flange portion is provided in an extending direction of the elastic member, the flange portion is provided in a ring-like structure, and the second screw thread segment is provided on an outer peripheral wall surface of the flange portion.

Optionally, the adjusting member is provided with a positioning portion, the positioning portion is arranged on one side, close to the elastic member, of the flange portion in a protruding mode, and one end, close to the adjusting member, of the elastic member is sleeved on the periphery of the positioning portion.

Optionally, the supporting structure comprises a supporting frame, a guide sleeve piece and at least one guide bearing, the supporting frame is installed in the valve body, the guide sleeve piece is fixedly arranged on the supporting frame, the guide bearing is installed in an inner cavity of the guide sleeve piece, and the guide sleeve piece and the guide bearing are respectively in sliding configuration with the valve clack; the first thread section is formed on the supporting frame.

Optionally, a receiving cavity is formed on a side of the support frame facing the guide sleeve member, a flow hole is formed in the adjusting member, and the flow hole is communicated with the receiving cavity.

Optionally, be equipped with on the valve clack and extend the cover portion, be equipped with spacing chamber in the extension cover portion, the elastic component is kept away from the spacing butt setting of one end of regulating part is in spacing intracavity.

Optionally, the adjusting assembly further comprises a weight member, and the weight member is mounted at one end of the extension sleeve portion, which is close to the adjusting member.

An axial flow check valve comprises a valve body, a valve clack and the adjusting component; the valve body and the valve clack are configured to be movably connected.

Optionally, a circulation port is arranged on the valve body, and the valve clack moves away from or close to and abuts against the circulation port under the action of external force so as to open or close the check valve;

the valve clack is provided with an extension sleeve part and a check part, the check part is arranged at one end of the extension sleeve part, which is close to the circulation port, and the check side of the check part is arranged towards the circulation port.

Optionally, at least one pressure balance hole is arranged on the extension sleeve part, and the inner cavity of the extension sleeve part is communicated with the flow channel cavity of the valve body; a guide wall surface is arranged on one side of the non-return part, which is away from the non-return side of the non-return part, and the pressure balance hole is adjacent to the guide wall surface; and/or

The valve body is provided with a transition wall surface, the circulation port and the transition wall surface are in round corner transition, the valve body is in a revolving body structure, the position, adjacent to the circulation port, of the transition wall surface is provided with an expanding section, and the radius of the expanding section is larger than that of the circulation port; and/or

The valve body is provided with a first hard sealing layer, the check side of the check part is provided with a second hard sealing layer, the check valve is in a closed state, and the first hard sealing layer and the second hard sealing layer are in butt fit.

The technical scheme provided by the utility model has the following advantages:

1. according to the adjusting component provided by the utility model, through the sliding pair formed between the first thread section and the second thread section, the external force can act on the adjusting piece to slide to be close to or far away from the elastic piece, so that the relative distance between the adjusting piece and the valve clack is changed, the elastic piece is in different compression lengths, different elastic pretightening forces can be configured according to the pressure of different fluid media, and the check capacity of the configuration valve can be flexibly adjusted; the elastic pieces with different elastic coefficients can be replaced by disassembling the adjusting piece and the supporting structure, so that the use conditions of acting forces of different fluid media can be better adapted, and the practicality of the adjusting component can be improved.

2. According to the adjusting component provided by the utility model, the flange part is abutted against the elastic piece, when the adjusting piece moves close to the valve clack, the compression effect on the elastic piece can be improved, the extension length of the elastic piece is relatively reduced, so that the pretightening force for increasing the valve clack is generated, the second thread section is arranged on the peripheral wall surface of the flange part, and the first thread section and the second thread section are in threaded connection and matched to change the relative distance between the adjusting piece and the valve clack, so that the purpose of adjusting the elastic piece to generate different elastic pretightening forces is realized, and the adjusting operation is convenient.

3. According to the adjusting component provided by the utility model, one end of the elastic piece is in limit installation through the flange part and the positioning part, and the other end of the elastic piece is in limit installation through the limit cavity of the extension sleeve part, so that the elastic piece has good limit stability, and the extension sleeve part forms peripheral protection for the elastic piece; the elastic piece both ends are installed through the mode of cup jointing respectively, and it is favorable to promoting the elastic piece assembly convenient.

4. According to the axial flow type check valve provided by the utility model, the opening resistance of the check valve can be adjusted through the adjusting component, the relative distance between the adjusting component and the valve clack is changed, and the elastic component can be in different compression lengths, so that different elastic pretightening forces can be configured according to the pressure of different fluid media, the check capacity of the configured check valve can be flexibly adjusted, and the axial flow type check valve can be adapted to the use working conditions of different fluid media acting forces.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present utility model, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic structural view of an axial flow check valve provided in an embodiment of the present utility model;

FIG. 2 is a schematic view of the structure of a support structure in an adjustment assembly provided in an embodiment of the present utility model;

FIG. 3 is an enlarged partial schematic view of FIG. 2A;

FIG. 4 is a schematic view of the structure of an adjusting member in an adjusting assembly according to an embodiment of the present utility model;

FIG. 5 is a schematic view of the structure of a valve body in an axial flow check valve provided in an embodiment of the present utility model;

FIG. 6 is a schematic structural view of a valve flap in an axial flow check valve provided in an embodiment of the present utility model;

reference numerals illustrate:

11-a supporting frame; 111-a first thread segment; 113-a receiving cavity; 12-a guide sleeve member; 13-guiding bearings;

21-a valve body; 211-flow port; 212-transition wall surface; 213-a first hard seal layer;

22-valve clack; 221-an extension sleeve portion; 222-a limiting cavity; 223-a check; 224-pressure balance hole; 225, a diversion wall surface; 226-a second hard seal layer;

31-an elastic member; 32-an adjusting member; 321-a second thread segment; 322-flange portion; 323-a positioning part; 324-a flow hole; 33-weight piece.

Detailed Description

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In addition, the technical features of the different embodiments of the present utility model described below may be combined with each other as long as they do not collide with each other.

Example 1

The present embodiment provides an adjustment assembly, see fig. 1 to 4, comprising a support structure, a valve flap 22, an elastic member 31 and an adjustment member 32, the support structure being adapted to be fixedly mounted within the valve body 21; the valve clack 22 and the supporting structure are movably arranged; one end of the elastic piece 31 is detachably connected with the adjusting piece 32, the other end of the elastic piece 31 is suitable for being in limiting connection with the valve clack 22, the adjusting piece 32 and the supporting structure are configured to be in movable connection, a first thread section 111 is arranged on the supporting structure, a second thread section 321 is arranged on the adjusting piece 32, and the first thread section 111 and the second thread section 321 are correspondingly matched in a conformal manner and are configured to form a sliding pair; under the action of external forces, the adjusting member 32 has an adjusting state of sliding close to or away from the valve flap 22 relative to the support structure to configure the biasing force of the elastic member 31 on the valve flap 22.

According to the adjusting assembly provided by the embodiment, through the sliding pair formed between the first thread section 111 and the second thread section 321, the adjusting piece 32 can be acted by external force to slide close to or far from the elastic piece 31, so that the relative distance between the adjusting piece 32 and the valve clack 22 is changed, and the elastic piece 31 is in different compression lengths, so that different elastic pretightening forces can be configured according to the pressure of different fluid media, and the check capacity of the configuration valve can be flexibly adjusted; the adjusting piece 32 and the supporting structure can be detached to replace the elastic piece 31 with different elastic coefficients, so that the use condition of acting force of different fluid media can be better adapted, and the practicality of the adjusting component can be improved.

Referring to fig. 4, the adjusting member 32 is provided with a flange portion 322, and in the adjusted state, the flange portion 322 and the elastic member 31 are abutted and fitted; the flange portion 322 is provided in the extending direction of the elastic member 31, the flange portion 322 is provided in a ring-like structure, and the second screw thread section 321 is provided on the outer peripheral wall surface of the flange portion 322.

In the adjusting assembly provided in this embodiment, the flange portion 322 abuts against the elastic member 31, so that when the adjusting member 32 moves close to the valve clack 22, the compression effect on the elastic member 31 can be improved, and the extension length of the elastic member 31 is relatively reduced, so that an increased pre-tightening force is generated on the valve clack 22; when the adjusting element 32 moves away from the valve flap 22, the compression of the elastic element 31 can be reduced, so that the extension of the elastic element 31 is relatively increased, and a reduced pretension force to the valve flap 22 is generated.

In this embodiment, referring to fig. 4, the second threaded section 321 is disposed on the outer peripheral wall surface of the flange portion 322, and the first threaded section 111 and the second threaded section 321 are in threaded connection and fit, so as to change the relative distance between the adjusting member 32 and the valve clack 22, thereby achieving the purpose of adjusting the elastic member 31 to generate different elastic pretightening forces, and the adjustment operation is convenient.

In some embodiments, the adjustment member 32 is configured as a compression ring that is a hard material.

Referring to fig. 1 and 2, the support structure includes a support frame 11, a guide sleeve member 12 and a guide bearing 13, the support frame 11 is installed in the valve body 21, the guide sleeve member 12 is fixedly arranged on the support frame 11, the guide bearing 13 is installed in an inner cavity of the guide sleeve member 12, and the guide sleeve member 12 and the guide bearing 13 are respectively slidably configured with the valve clack 22.

In the present embodiment, referring to fig. 3, a first screw section 111 is formed on a support frame 11, the support frame 11 is provided with a through-hole structure, an adjusting member 32 is installed in the through-hole structure, and the first screw section 111 is provided on an inner peripheral wall surface of the through-hole structure.

Referring to fig. 2, two guide bearings 13 are provided, and the two guide bearings 13 limit the sliding of the valve clack 22 respectively, so as to enhance the alignment capability of the movement of the valve clack 22 in the same desired direction, and the two guide bearings 13 are arranged at two ends of the guide sleeve member 12 in the length direction at intervals, so as to enhance the coaxiality of the sliding axis of the valve clack 22 and the guide direction of the guide sleeve member 12, reduce the radial runout of the movement of the valve clack 22, and promote the fluency of the movement of the valve clack 22.

Referring to fig. 2 and 4, the supporting frame 11 is configured to form a receiving chamber 113 toward one side of the guide sleeve 12, and the adjusting member 32 is provided with a through-hole 324, and the through-hole 324 is disposed in communication with the receiving chamber 113. The communication between the receiving chamber 113 and the flow passage chamber of the valve body 21 through the flow hole 324 is advantageous in improving the flow capacity of the fluid medium.

Referring to fig. 4, the adjusting member 32 is provided with a positioning portion 323, the positioning portion 323 is arranged on one side of the flange portion 322 close to the elastic member 31 in a protruding manner, and one end of the elastic member 31 close to the adjusting member 32 is sleeved on the periphery of the positioning portion 323; the valve clack 22 is provided with an extension sleeve part 221, a limiting cavity 222 is arranged in the extension sleeve part 221, and one end of the elastic piece 31, which is far away from the adjusting piece 32, is in limiting abutting connection with the limiting cavity 222. One end of the elastic piece 31 is mounted in a limiting mode through the flange part 322 and the positioning part 323, the other end of the elastic piece 31 is mounted in a limiting mode through the limiting cavity 222 of the extension sleeve part 221, so that the elastic piece 31 has good limiting stability, and the extension sleeve part 221 forms peripheral protection of the elastic piece 31; the two ends of the elastic piece 31 are respectively installed in a sleeving manner, which is beneficial to promoting the convenience and rapidness in assembling the elastic piece 31.

Referring to fig. 1, the adjustment assembly further includes a weight member 33, and the weight member 33 is mounted to an end of the extension sleeve portion 221 adjacent to the adjustment member 32. The weight 33 arranged at one end of the extension sleeve part 221 improves the self weight balance of the valve clack 22, can balance the vibration influence of the non-return side of the valve clack 22, and can guide the movement path of the valve clack 22 through the sliding of the guide sleeve part 12 and the guide bearing 13, thereby jointly improving the movement precision and stability of the valve clack 22.

Example 2

The present embodiment provides an axial flow check valve comprising a valve body 21, a valve flap 22, and the regulating assembly of embodiment 1; the valve body 21 and the flap 22 are configured for a movable connection. According to the embodiment, the opening resistance of the check valve can be adjusted through the adjusting component, the relative distance between the adjusting piece 32 and the valve clack 22 is changed, and the elastic piece 31 can be in different compression lengths, so that different elastic pretightening forces can be configured according to the pressure of different fluid media, the check capacity of the check valve can be flexibly adjusted and configured, and the axial flow check valve can be adapted to the use working conditions of the acting forces of different fluid media.

Referring to fig. 1, 5 and 6, a flow port 211 is provided on the valve body 21, and the valve flap 22 moves away from or close to the flow port 211 to open or close the check valve under the action of an external force; the valve flap 22 is provided with an extension sleeve 221 and a check portion 223, the check portion 223 is provided at one end of the extension sleeve 221 near the flow port 211, and the check side of the check portion 223 is provided toward the flow port 211.

Referring to fig. 6, a pressure balance hole 224 is formed on the extension sleeve 221, the extension sleeve 221 is movably disposed in the guide cavity, and the inner cavity of the extension sleeve 221 is communicated with the flow channel cavity of the valve body 21; the side of the non-return portion 223 facing away from the non-return side thereof is provided with a guide wall surface 225, and the pressure balance hole 224 is arranged adjacent to the guide wall surface 225; the pressure balance holes 224 may be annularly distributed at one end of the extension sleeve 221 near the non-return portion 223, and one end of each pressure balance hole 224 is communicated with the flow channel cavity, and the other end is communicated with the inner cavity of the extension sleeve 221. When the medium flows back, the fluid medium flows back through the pressure balance holes 224 in a rapid diffusion manner, so that the valve clack 22 is promoted to form sealing force rapidly, the flow of the fluid medium flows back to the pressure balance holes 224 through the flow guide wall surface 225, the distribution and diffusion process of the fluid medium is accelerated, and the sealing capability of the closing response of the check valve is enhanced.

Referring to fig. 5, a transition wall 212 is disposed on the valve body 21, the flow port 211 and the transition wall 212 are rounded and transitionally disposed, the valve body 21 is in a revolving structure, for example, an umbrella structure, and a diameter expanding section is disposed at a position of the transition wall 212 adjacent to the flow port 211, and the radius of the diameter expanding section is larger than that of the flow port 211. The expansion of the transition wall 212 increases the flow space of the fluid medium when the check valve is opened, thereby promoting the discharge of the fluid medium.

Referring to fig. 5 and 6, the valve body 21 is provided with a first hard seal layer 213, and the check side of the check portion 223 is provided with a second hard seal layer 226; the check valve is in a closed state, and the first hard seal layer 213 and the second hard seal layer 226 are in a conformal abutting fit. A first hard sealing layer 213 is provided at the flow-through opening 211, the hard sealing layer being provided in a sealing convex structure. The hard sealing layer can be made of stellite through overlaying, and has the advantages of simple sealing structure, single-pass sealing, good sealing performance and low cost.

The axial-flow check valve that this embodiment provided, the check valve is in the working phase: the flow channel cavity of the valve body 21 is opened or closed back and forth through the valve clack 22, and when the valve is opened, the valve clack 22 is pushed to be opened by the acting force of the fluid medium against the spring force and the friction force of the elastic piece 31; the elastic element 31 can play a role in buffering by absorbing energy of the fluid medium acting to open the valve clack 22 through the elastic element 31; when the acting force of the fluid medium on the valve clack 22 is smaller than the elastic force of the elastic member 31, the elastic member 31 acts on the valve clack 22 to gradually close the flow passage cavity of the valve body 21, the check part 223 covers and seals the flow passage opening 211, and the first hard sealing layer 213 and the second hard sealing layer 226 are in abutting contact so as to prevent the backflow of the fluid medium. By relatively rotating the adjusting member 32 and the supporting frame 11, the adjusting member 32 is moved toward or away from the valve clack 22 to gradually compress or gradually release the elastic member 31 between the adjusting member 32 and the valve clack 22, thereby changing the pre-tightening force of the elastic member 31 on the valve clack 22, and thus realizing the adjustment of the opening resistance of the check valve.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the utility model.

Claims (10)

1. An adjustment assembly, comprising:

a support structure adapted to be fixedly mounted within the valve body (21);

a valve flap (22), the valve flap (22) being movably arranged with the support structure;

the device comprises an elastic piece (31) and an adjusting piece (32), wherein one end of the elastic piece (31) is detachably connected with the adjusting piece (32), the other end of the elastic piece (31) is suitable for being in limiting connection with a valve clack (22), the adjusting piece (32) is movably connected with a supporting structure, a first threaded section (111) is arranged on the supporting structure, a second threaded section (321) is arranged on the adjusting piece (32), and the first threaded section (111) and the second threaded section (321) are correspondingly matched in a conformal mode and are structurally provided with sliding pairs;

under the action of external force, the adjusting piece (32) is provided with an adjusting state of sliding close to or away from the valve clack (22) relative to the supporting structure so as to configure the biasing force of the elastic piece (31) on the valve clack (22).

2. An adjustment assembly according to claim 1, characterized in that the adjustment member (32) is provided with a flange portion (322), the flange portion (322) and the elastic member (31) being in abutment engagement in the adjustment state; the flange portion (322) is provided in the extending direction of the elastic member (31), the flange portion (322) is provided in a ring-like structure, and the second screw thread section (321) is provided on the outer peripheral wall surface of the flange portion (322).

3. The adjusting assembly according to claim 2, wherein the adjusting member (32) is provided with a positioning portion (323), the positioning portion (323) is arranged on one side, close to the elastic member (31), of the flange portion (322) in a protruding mode, and one end, close to the adjusting member (32), of the elastic member (31) is sleeved on the periphery of the positioning portion (323).

4. An adjustment assembly according to claim 1, characterized in that the support structure comprises a support frame (11), a guide sleeve member (12) and at least one guide bearing (13), the support frame (11) being mounted in the valve body (21), the guide sleeve member (12) being fixedly arranged on the support frame (11), the guide bearing (13) being mounted in an inner cavity of the guide sleeve member (12), the guide sleeve member (12) and the guide bearing (13) being respectively slidably arranged with the valve flap (22); the first thread segment (111) is formed on the support frame (11).

5. The adjusting assembly according to claim 4, wherein a receiving chamber (113) is formed on a side of the supporting frame (11) facing the guide sleeve member (12), a through hole (324) is formed in the adjusting member (32), and the through hole (324) is in communication with the receiving chamber (113).

6. The adjusting assembly according to any one of claims 1-5, wherein the valve clack (22) is provided with an extending sleeve part (221), a limiting cavity (222) is arranged in the extending sleeve part (221), and one end, far away from the adjusting piece (32), of the elastic piece (31) is in limiting abutting connection with the limiting cavity (222).

7. The adjustment assembly of claim 6, further comprising a weight member (33), the weight member (33) being mounted at an end of the extension sleeve portion (221) adjacent the adjustment member (32).

8. An axial flow check valve comprising a valve body (21), a valve flap (22) and an adjustment assembly according to any one of claims 1-7; the valve body (21) and the valve clack (22) are configured to be movably connected.

9. The axial flow check valve according to claim 8, wherein a flow port (211) is provided on the valve body (21), and the valve flap (22) moves away from or close to abut against the flow port (211) under the action of an external force to open or close the check valve;

the valve clack (22) is provided with an extension sleeve part (221) and a check part (223), the check part (223) is arranged at one end, close to the circulation port (211), of the extension sleeve part (221), and the check side of the check part (223) is arranged towards the circulation port (211).

10. The axial flow check valve according to claim 9, wherein the extension sleeve portion (221) is provided with at least one pressure balance hole (224), and an inner cavity of the extension sleeve portion (221) is communicated with a flow channel cavity of the valve body (21); a guide wall surface (225) is arranged on one side of the non-return part (223) away from the non-return side, and the pressure balance hole (224) is adjacent to the guide wall surface (225); and/or

The valve body (21) is provided with a transition wall surface (212), the circulation port (211) and the transition wall surface (212) are arranged in a round corner transition mode, the valve body (21) is in a revolving body structure, a diameter expansion section is arranged at the position, adjacent to the circulation port (211), of the transition wall surface (212), and the radius of the diameter expansion section is larger than that of the circulation port (211); and/or

The valve body (21) is provided with a first hard sealing layer (213), the non-return side of the non-return part (223) is provided with a second hard sealing layer (226), the non-return valve is in a closed state, and the first hard sealing layer (213) and the second hard sealing layer (226) are in abutting fit.