A horizontal shaft eccentric hemispherical valve

Abstract

The present invention discloses a horizontal axis eccentric hemispherical valve, which adopts a horizontal axis structure to install the valve core, and the axis of the valve stem is perpendicular to the flow direction of the medium in the valve body and is arranged horizontally, so as not to occupy the lower end of the flow channel, so that the lower end of the flow channel can be designed to be flatter than that of a vertical eccentric hemispherical valve, thereby reducing the flow resistance. The valve core is provided with a cylindrical boss concentric with the valve core, and a sealing ring is provided in the gap on the boss, the sealing ring has a spherical crown-shaped sealing surface, and an air bag ring is provided in the gap formed by the boss and the sealing ring. The sealing ring and the valve core are fixed by a fixing assembly, so that the valve core sealing spherical crown and the valve seat center can be adjusted to be concentric during assembly, so as to overcome the processing error and ensure effective sealing.

Description

Technical Field

[0001] The invention relates to the field of valves, in particular to a horizontal shaft eccentric hemispherical valve. Background Art

[0002] Ball valves are mainly used in pipelines to cut off, distribute and change the flow direction of media, and are widely used in the fields of petroleum, chemical industry, metallurgy, textile, food, atomic energy, aviation, etc. Eccentric ball valve is a relatively new type of ball valve. It has some advantages unique to its structure. It can be tightly closed by rotating 90° and applying very small torque. There is no friction when opening and closing, the seal is not easy to wear, the opening and closing torque is small, and the specifications of the actuator can be reduced.

[0003] At present, the eccentric hemispherical valves on the market are basically designed and produced according to the standard of "GB / T26146-2010 Eccentric Hemispherical Valve", and the products are basically vertical shaft structures. Vertical shaft installation has at least the following disadvantages:

[0004] 1. High vertical space requirements;

[0005] 2. The valve core needs to occupy the lower end of the flow channel, making the curvature of the flow channel in the inner cavity of the valve body larger, increasing the flow resistance of the medium;

[0006] 3. After long-term use, the main seal pair on the valve core is worn and cannot be completely repaired online.

[0007] On the other hand, the sealing of conventional hard-sealed ball valves relies on the precise extrusion sealing of the valve seat sealing surface and the valve core sealing surface, which requires very high processing accuracy and installation accuracy of the valve seat sealing surface and the valve core sealing surface. However, due to the eccentricity of the eccentric hemispherical valve, in order to ensure the sealing reliability of the main valve seal, it is necessary to ensure that the center of the valve core hemisphere is concentric with the center of the valve seat. Since the valve core, valve seat and valve body are processed separately, the eccentric distance of the valve core and valve body cannot be exactly the same, and there must be accumulated errors in the process. If this error is too large, it will cause the main valve seal to leak unreliably or the valve torque to be too large, affecting the sealing effect. In severe cases, it may cause the seal to fail and the valve to be scrapped. Therefore, there is a saying in the market that eccentric ball valves are difficult to process and the price is also high.

[0008] In Chinese invention patent CN201811224835.X, an eccentric ball valve is disclosed. The valve seat can be slightly moved on the valve cover through an adjustable mounting structure. When the valve ball rotates to gradually squeeze and contact the valve ball sealing surface with the valve seat sealing surface under the drive of the operating mechanism, the valve seat can be slightly moved, so that the valve ball sealing surface and the valve seat sealing surface can achieve a uniform pressure seal, thereby solving the above technical problems. However, the eccentric ball valve is installed on the valve body by floating the valve seat. In order to ensure that the valve seat can float smoothly in the annular groove, the structure itself is a clearance fit. In addition, the repeated wear of the valve seat end face and the inner wall of the annular groove will lead to a loose seal, so that the medium flows into the tiny gap between the outer circumference of the valve seat and the bottom surface of the annular groove. The accumulation and crystallization of the medium will block the tiny gap, causing the valve seat to lose its fine-tuning function, or only the tiny gap below will be blocked, causing the eccentric seal of the valve seat to fail. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide a horizontal shaft eccentric semi-ball valve which can adjust the valve core sealing ball crown and the valve seat center to be concentric during assembly, overcome the processing error, and ensure effective sealing.

[0010] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0011] A horizontal shaft eccentric hemispherical valve, comprising:

[0012] The valve body has an inlet end and an outlet end at both horizontal ends, and a valve cover is provided on the upper part of the valve body to seal the valve body, and a valve cavity is formed between the valve cover and the valve body;

[0013] A valve seat assembly, annularly sealed, fixed to the step at the outlet end of the valve body; and

[0014] A valve core is rotatably disposed in the valve cavity via a valve stem;

[0015] It is characterized in that

[0016] The axis of the valve stem is perpendicular to the direction of medium flow in the valve body and is arranged horizontally;

[0017] The valve core has a concentric cylindrical boss, a sealing ring is sleeved in the gap on the boss, the sealing ring has a spherical crown-shaped sealing surface, an air bag ring is arranged in the gap formed by the boss and the sealing ring, and the sealing ring and the valve core are fixed by a fixing assembly;

[0018] The valve core is driven to rotate along the valve stem in the direction of medium flow, so that the ball crown of the sealing ring and the valve seat assembly cooperate to seal.

[0019] A further technical solution is that a through adjustment hole is opened on the valve body on one side of the outlet end, and a top piece that can adjust the horizontal position of the valve seat assembly is arranged in the adjustment hole, so that the valve seat assembly is sealed against the sealing ring.

[0020] A further technical solution is that the valve seat assembly comprises:

[0021] The main sealing ring has a trapezoidal cross section; and

[0022] A valve seat, which is sealed with the valve body via a sealing ring, and the valve seat cooperates with a pressure ring to form a valve groove matching the main sealing ring;

[0023] The main sealing ring is arranged in the valve groove and is fixed by pressing the pressing ring. The small end of the main sealing ring is exposed and protrudes from the valve seat surface to contact the sealing ring.

[0024] The pressure ring and the valve seat are fixed by a plurality of screws on the end surface.

[0025] A further technical solution is that the valve seat assembly further includes:

[0026] a gasket, which is provided at the outer end of the valve seat; and

[0027] An elastic buffer pad is provided between the gasket and the valve seat;

[0028] The valve body, valve seat, elastic buffer pad and valve seat are connected and fixed by tightening screws.

[0029] A further technical solution is that the fixing assembly includes a plurality of connecting screws uniformly distributed in the circumferential direction and a plurality of positioning pins staggered with the connecting screws.

[0030] A further technical solution is that the valve stem comprises a valve stem 1 and a valve stem 2 which are coaxially arranged at both ends;

[0031] The valve stem is fixed to the valve body in a sealing manner and is rotatably connected to the valve core via a shaft sleeve;

[0032] The valve stem 2 is rotatably connected to the valve body through a shaft sleeve and fixed to the valve core. The valve stem 2 is externally connected to a power head.

[0033] A further technical solution is that the axial position of the valve stem 1 is adjustable via an adjusting assembly.

[0034] A further technical solution is that the adjustment component comprises:

[0035] The end cover, whose positioning sleeve is sealed and embedded in the outlet of the valve body, and whose flange is placed outside the valve body, is provided with a through adjustment hole on the flange of the end cover, and a top piece 2 capable of adjusting the distance between the flange and the valve body is provided in the adjustment hole;

[0036] The outer end of the valve stem 1 is provided with a stepped shaft 1, and the stepped shaft 1 is located in the positioning sleeve of the end cover and fixed.

[0037] A further technical solution is that the inner end of the valve stem 1 has a stepped shaft 2, the stepped shaft 2 is fixed to the valve core, and a hemispherical gasket is provided at the step of the stepped shaft 2.

[0038] A further technical solution is that the end surface of the sealing ring and the valve core are sealed by a sealing ring.

[0039] The beneficial effects of adopting the above technical solution are:

[0040] The eccentric hemispherical valve adopts a horizontal shaft structure to install the valve core, which does not occupy the lower end of the flow channel, so that the lower end of the flow channel can be designed to be flatter than the vertical eccentric hemispherical valve, reducing the flow resistance;

[0041] When the main sealing parts of the valve are damaged and need to be repaired or replaced, the valve can be turned to the open position without removing the valve from the pipeline, so that the valve core faces the valve cover upward, and the valve cover can be opened online. The sealing ring can be directly removed from the upper opening of the valve body; if the valve seat assembly needs to be replaced, the valve core can be rotated toward the inlet end to make room for replacement and repair of the valve seat assembly, so that online maintenance can be achieved without removing the valve body, which is convenient for maintenance;

[0042] In the semi-ball valve structure, a reasonable space for movement is reserved between the spherical crown-shaped sealing ring and the valve core, and an airbag ring is arranged in the gap, and the airbag ring is inflated to expand it. Since the pressure of the gas in the airbag ring is balanced, the position of the sealing ring is adjusted by utilizing the expansion of the airbag, so that the spherical crown surface and the sealing surface of the valve seat assembly can be evenly contacted, so that a uniform pressure seal can be achieved between the sealing surface of the valve core and the sealing surface of the valve seat. After adjusting the center of the valve core and the valve seat to an ideal concentric position, the sealing ring is fixed on the valve core, thereby ensuring a reasonable sealing pressure ratio of the main seal, reducing the valve torque, and ensuring long-term effective use. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0044] Figure 1 This is a structural schematic diagram of the horizontal shaft eccentric hemispherical valve in a closed state;

[0045] Figure 2 This is a structural schematic diagram of the horizontal shaft eccentric semi-ball valve in the open state;

[0046] Figure 3 yes Figure 1 The enlarged structural diagram of the middle A part;

[0047] Figure 4 yes Figure 2A schematic diagram of the enlarged structure of the middle B part;

[0048] Figure 5 It is a structural schematic diagram of the horizontal shaft eccentric semi-ball valve in a maintenance state. DETAILED DESCRIPTION

[0049] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0050] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0051] like Figure 1 to Figure 5 As shown, a horizontal eccentric semi-ball valve is installed on a pipeline and is used to open / close the pipeline to control the flow of the medium in the pipeline. Here, the medium can be liquid and gas.

[0052] The eccentric hemispherical valve includes a valve body 1, a valve seat assembly 3 and a valve core 4. The two horizontal ends of the valve body 1 have an inlet end and an outlet end. A valve cover 2 is provided on the upper part of the valve body 1 to seal the valve. A valve cavity is formed between the valve cover 2 and the valve body 1. A hanging buckle is connected to the valve cover 2 to cooperate with external lifting equipment to realize the transportation of the eccentric hemispherical valve. The valve seat assembly 3 is annularly sealed and fixed to the step at the outlet end of the valve body 1. The valve core 4 is rotatably arranged in the valve cavity through the valve stem. The sealing surface of the valve core 4 and the sealing surface of the valve seat assembly 3 are squeezed and sealed to close the flow channel in the valve body 1 and cut off the outflow of the medium.

[0053] In the horizontal shaft eccentric semi-ball valve disclosed in the present invention, the axis of the valve stem is perpendicular to the direction of medium flow in the valve body 1 and is arranged horizontally.

[0054] Specifically, the valve stem includes a valve stem 1 81 and a valve stem 2 82 which are coaxially arranged at both ends. The valve stem 1 81 is sealed and fixed to the valve body 1 and is rotatably connected to the valve core 4 through a shaft sleeve; the valve stem 2 82 is rotatably connected to the valve body 1 through a shaft sleeve and is fixed to the valve core 4. The valve stem 2 82 is externally connected to a power head 83, which is an actuator and can be a manual worm gear transmission device or an automatic worm gear transmission device. The power head 83 drives the valve stem 2 82 to rotate, thereby realizing the driving of the valve core 4 to rotate.

[0055] The eccentric semi-ball valve adopts a horizontal shaft structure to install the valve core 4, which does not occupy the lower end of the flow channel, so that the lower end of the flow channel can be designed to be flatter than that of a vertical eccentric semi-ball valve, thereby reducing flow resistance.

[0056] When the main sealing parts of the valve are damaged and need to be repaired or replaced, the valve can be turned to the open position without removing the valve from the pipeline. Figure 2 As shown, the valve core 4 is directed upward toward the valve cover 2, the valve cover 2 is opened online, and the sealing ring 5 can be directly removed from the upper opening of the valve body 1; if the valve seat assembly 3 needs to be replaced, the valve core 4 can be rotated toward the inlet end, as shown in FIG. Figure 5 As shown, by making room, the valve seat assembly 3 can be replaced and repaired, and online maintenance can be achieved without disassembling the valve body 1, which is convenient for maintenance.

[0057] The valve core 4 has a cylindrical boss concentric with it, and a sealing ring 5 is sleeved in the gap on the boss. The sealing ring 5 has a spherical crown sealing surface, and an air bag ring 6 is arranged in the gap formed by the boss and the sealing ring 5. The sealing ring 5 and the valve core 4 are fixed by a fixing assembly, and the end face of the sealing ring 5 and the valve core 4 are sealed by a sealing ring. The valve core 4 is driven to rotate along the valve stem in the direction of medium flow, so that the spherical crown of the sealing ring 5 cooperates with the valve seat assembly 3 for sealing.

[0058] The fixing assembly includes a plurality of connecting screws evenly distributed in the annular direction and a plurality of positioning pins staggered with the connecting screws. Since the sealing ring 5 and the valve core 4 are matched with a large gap, in order to prevent the sealing ring 5 from being loosened under force, after the installation and commissioning is completed, positioning pins are installed on the sealing ring 5 and the valve core 4 to firmly lock the ball crown in the adjusted position, which is also convenient for positioning after maintenance and disassembly. In order to cooperate with the adjustment of the sealing ring 5, the hole for the connecting screw on the sealing ring 5 is a large-diameter stepped light hole, leaving an adjustment gap so that the stepped light hole can still correspond to the threaded hole on the valve core after adjustment, and screws are installed to tighten the sealing ring 5. Since there are gaps between the connecting screw and the matching light hole on the sealing ring 5 and between the sealing ring 5 and the valve core 4, in order to prevent the sealing ring 5 from sagging due to its own weight or other special factors after the valve has been used for a period of time, resulting in sealing failure, positioning pins are also required.

[0059] In the semi-ball valve structure, a reasonable space clearance is reserved between the spherical crown-shaped sealing ring 5 and the valve core 4, and an airbag ring 6 is arranged in the clearance, and the airbag ring 6 is inflated to expand. Since the pressure of the gas in the airbag ring 6 is balanced, the position of the sealing ring 5 is adjusted by utilizing the expansion of the airbag, so that the spherical crown surface and the sealing surface of the valve seat assembly 3 can be evenly contacted, so that the sealing surface of the valve core 4 and the sealing surface of the valve seat 32 can be sealed with uniform pressure. After adjusting the center of the valve core 4 and the valve seat 32 to an ideal concentric position, the sealing ring 5 is fixed on the valve core 4, so as to ensure a reasonable sealing pressure ratio of the main seal, reduce the valve torque, and ensure long-term effective use.

[0060] In the horizontal shaft eccentric semi-ball valve disclosed in the present invention, a through adjustment hole is provided on the valve body 1 on one side of the outlet end, and a top piece 7 capable of adjusting the horizontal position of the valve seat assembly 3 is provided in the adjustment hole, so that the valve seat assembly 3 is sealed against the sealing ring 5. The top piece 7 can be a top screw screwed in the adjustment hole. The top piece 7 can drive the valve seat assembly 3 to approach or move away from the valve core 4, so that the position of the valve seat assembly 3 in the valve body 1 can be adjusted, so that the valve seat assembly 3 can better cooperate with the spherical crown surface on the valve core 4 to achieve sealing, and avoid leakage points and the like in the sealing of the eccentric semi-ball valve.

[0061] An adjustment gap is pre-set between the valve seat assembly 3 and the valve body 1. During installation, pressurized water is poured into the water inlet of the valve, and the adjustment screw on the valve body 1 is adjusted to push the valve seat assembly 3 toward the ball crown surface little by little in the horizontal direction until the main seal is leak-proof. Do not over-tighten it. The main seal is fine if it is leak-proof. This is to prevent the main seal ring 31 from being over-pressurized. The sealing pressure ratio is too large, which reduces the life of the seal ring and increases the opening and closing torque of the valve. After adjusting the adjustment screw, tighten the clamping screw set at the outlet end of the valve body 1 to lock the adjusted position of the valve seat 32.

[0062] The valve seat assembly 3 includes a main sealing ring 31 and a valve seat 32. The cross section of the main sealing ring 31 is trapezoidal. The valve seat 32 and the valve body 1 are sealed by the sealing ring. The valve seat 32 cooperates with a pressure ring 33 to form a valve groove matching the main sealing ring 31. The main sealing ring 31 is arranged in the valve groove and is pressed and fixed by the pressure ring 33. The small end of the main sealing ring 31 is exposed and protrudes from the surface of the valve seat 32 to contact the sealing ring 5. The pressure ring 33 and the valve seat 32 are fixed by multiple screws on the end surface.

[0063] In the horizontal eccentric semi-ball valve disclosed in the present invention, the sealing pair is a soft and hard double seal, that is, the valve seat 32 body is made of stainless steel, and there is a raised rubber main sealing ring 31 that is sealed with the stainless steel surface on the ball crown of the sealing ring 5. When the valve is closed, the main sealing ring 31 is first compressed to form a soft seal, and then the annular ball crown and the valve seat 32 are hard sealed, and the sealing effect is good.

[0064] In addition, the main sealing ring 31 is pressed onto the valve seat 32 in a trapezoidal cross-section, which is convenient for disassembly and maintenance.

[0065] During the process of the valve stem rotating to open and close the valve core 4, the liquid it transports will cause the internal pressure of the valve body 1 to increase. Especially during the process of the valve opening, not only the pressure changes rapidly, but the vibration is also very strong. During the long-term opening and closing process, the sealing performance of the valve seat 32 will be reduced, which will easily cause the medium to leak.

[0066] Therefore, in the horizontal shaft eccentric hemispherical valve disclosed in the present invention, the valve seat assembly 3 further includes a gasket 34 and an elastic buffer pad 35. The gasket 34 is arranged at the outer end of the valve seat 32, and the elastic buffer pad 35 is arranged between the gasket 34 and the valve seat 32. The valve body 1, the valve seat 32, the elastic buffer pad 35 and the valve seat 32 are connected and fixed by a clamping screw. The setting of the elastic buffer pad 35 can effectively reduce shock and prevent medium leakage.

[0067] In the horizontal shaft eccentric semi-ball valve disclosed in the present invention, the axial position of the valve stem 81 can be adjusted by an adjusting component to ensure that the valve core 4 is concentric with the valve body 1.

[0068] The adjustment assembly includes an end cap 84, the shape of which is the same as that of the prior art, the positioning sleeve of the end cap 84 is sealed and embedded in the outlet of the valve body 1, and its flange is placed outside the valve body 1. A through adjustment hole is opened on the flange of the end cap 84, and a top piece 85 capable of adjusting the distance between the flange and the valve body 1 is provided in the adjustment hole. The outer end of the valve stem 1 81 also has a stepped shaft 1, which is located and fixed in the positioning sleeve of the end cap 84. The top piece 85 can also be a top screw threaded in the adjustment hole. By screwing in or out the top piece 85 so that the top piece 85 protrudes from the adjustment hole, the axial position of the end cap 84, i.e., the valve stem 1 81, can be adjusted.

[0069] In addition, the inner end of the valve stem 81 also has a stepped shaft 2, which is fixed to the valve core 4. A hemispherical washer 86 is provided at the step of the stepped shaft 2. The hemispherical washer is equivalent to a self-lubricating bearing made of copper, which can reduce the friction between the valve core 4 and the valve stem 81 and reduce the opening and closing torque of the valve.

[0070] The above are only preferred embodiments of the present invention. Any simple modification, deformation and equivalent substitution made by anyone to the present invention based on the contents of the present invention shall fall within the protection scope of the present invention.

Claims

1. A horizontal shaft eccentric hemispherical valve, comprising: The valve body (1) has an inlet end and an outlet end at two horizontal ends, and a valve cover (2) is provided on the upper part of the valve body (1) to seal the valve body, and a valve cavity is formed between the valve cover (2) and the valve body (1); A valve seat assembly (3) is annularly sealed and fixed to a step at the outlet end of the valve body (1); and A valve core (4) is rotatably arranged in the valve cavity via a valve stem; It is characterized in that The axis of the valve stem is perpendicular to the direction of medium flow in the valve body (1) and is arranged horizontally; The valve core (4) has a cylindrical boss which is concentric with the valve core (4), a sealing ring (5) is sleeved in the gap on the boss, the sealing ring (5) has a spherical crown-shaped sealing surface made of stainless steel, an air bag ring (6) is arranged in the gap formed by the boss and the sealing ring (5), and the sealing ring (5) and the valve core (4) are fixed by a fixing assembly; The valve core (4) is driven to rotate along the valve stem in the direction of medium flow, so that the ball crown of the sealing ring (5) cooperates with the valve seat assembly (3) to seal. The valve seat assembly (3) includes: A main sealing ring (31) having a trapezoidal cross section; and The valve seat (32) is made of stainless steel. The valve seat (32) and the valve body (1) are sealed by a sealing ring. The valve seat (32) cooperates with a pressure ring (33) to form a valve groove that matches the main sealing ring (31); The main sealing ring (31) is arranged in the valve groove and is pressed and fixed by a pressing ring (33). The small end of the main sealing ring (31) is exposed and protrudes from the surface of the valve seat (32) to contact with the sealing ring (5). When the valve is closed, the main sealing ring (31) is first compressed to form a soft seal, and then the ball crown contacts the valve seat (32) to form a hard seal. The pressure ring (33) and the valve seat (32) are fixed via a plurality of screws on the end surface.

2. The horizontal eccentric hemispherical valve according to claim 1, characterized in that: A through adjustment hole is provided on the valve body (1) at one side of the outlet end, and a top piece (7) capable of adjusting the horizontal position of the valve seat assembly (3) is provided in the adjustment hole so that the valve seat assembly (3) is in sealing contact with the sealing ring (5).

3. The horizontal eccentric hemispherical valve according to claim 1, characterized in that: The valve seat assembly (3) further comprises: a gasket (34) disposed on the outer end of the valve seat (32); and An elastic buffer pad (35) is arranged between the gasket (34) and the valve seat (32); The valve body (1), the valve seat (32), the elastic buffer pad (35) and the valve seat (32) are connected and fixed by means of compression screws.

4. The horizontal eccentric hemispherical valve according to claim 1, characterized in that: The fixing assembly comprises a plurality of connecting screws uniformly distributed in an annular direction and a plurality of positioning pins staggered with the connecting screws.

5. The horizontal eccentric hemispherical valve according to claim 1, characterized in that: The valve stem comprises a valve stem 1 (81) and a valve stem 2 (82) which are coaxially arranged at both ends; The valve stem (81) is sealed and fixed to the valve body (1), and is rotatably connected to the valve core (4) via a shaft sleeve; The second valve stem (82) is rotatably connected to the valve body (1) via a shaft sleeve and is fixed to the valve core (4). The second valve stem (82) is externally connected to a power head (83).

6. The horizontal eccentric hemispherical valve according to claim 5, characterized in that: The axial position of the valve stem 1 (81) is adjustable via an adjusting assembly.

7. The horizontal eccentric hemispherical valve according to claim 6, characterized in that: The adjustment component comprises: The end cover (84) has a positioning sleeve which is sealingly embedded in the outlet of the valve body (1), and a flange plate is placed outside the valve body (1). A through adjustment hole is provided on the flange plate of the end cover (84), and a top piece (85) capable of adjusting the distance between the flange plate and the valve body (1) is provided in the adjustment hole; The outer end of the valve stem (81) is provided with a stepped shaft (81), and the stepped shaft (81) is located in a positioning sleeve of the end cover (84) and fixed.

8. The horizontal eccentric hemispherical valve according to claim 7, characterized in that: The inner end of the valve stem 1 (81) is provided with a stepped shaft 2, the stepped shaft 2 is fixed to the valve core (4), and a hemispherical gasket (86) is provided at the step of the stepped shaft 2.

9. The horizontal eccentric hemispherical valve according to claim 1, characterized in that: The end surface of the sealing ring (5) and the valve core (4) are sealed via a sealing ring.

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