A high-temperature resistant butterfly valve

Abstract

This invention relates to a high-temperature resistant butterfly valve, belonging to the field of valve technology. It includes a main valve stem with a butterfly plate fixedly connected to it, and an upper valve stem connected to the main valve stem. The upper and main valve stems are connected to be able to rotate in circumferential direction and move relative to each other axially. Elastic elements are respectively provided between the upper and lower ends of the butterfly plate and the valve body, allowing the butterfly plate to float up and down within the valve body via these elastic elements. A first accommodating space exists between the upper end of the main valve stem and the upper valve stem, and a second accommodating space exists between the lower end of the main valve stem and the valve body. This high-temperature resistant butterfly valve features a dual-stem structure, with the main valve stem directly connected to the butterfly plate and indirectly connected to the main valve stem via the upper valve stem. This reduces the overall size of the valve stems used to drive the butterfly plate's rotation. When the main valve stem expands axially due to heat, the distance the butterfly plate needs to move to one side is reduced, thereby improving the sealing performance of the butterfly valve at high temperatures.

Description

Technical Field

[0001] This invention relates to the field of valve technology, and specifically to a high-temperature resistant butterfly valve. Background Technology

[0002] A butterfly valve is a valve structure in which the closing element (valve disc or butterfly plate) is a disc that rotates around the valve shaft to achieve opening and closing.

[0003] Currently, with the increasing application of butterfly valves in high-temperature fields, higher requirements are being placed on their high-temperature resistance performance. For example, Chinese patent document CN208605651U discloses a valve stem structure that, in order to be suitable for high-temperature conditions, adopts a floating butterfly valve seat structure and uses a diamond-shaped composite high-temperature resistant sealing ring of metal and flexible graphite in the selection of sealing materials, thereby ensuring that the butterfly valve structure can be used in operating conditions with temperatures higher than 200℃.

[0004] However, in the butterfly valve described above, since the valve stem and valve core are floatingly installed in the valve seat, when applied to higher temperature conditions, such as 650℃, the valve stem will expand axially due to heat changes, and the valve core connected to the valve stem will also move and shift axially along the valve stem. This will affect the butterfly plate from maintaining its normal sealing position, which is not conducive to ensuring the valve's sealing performance under high temperature conditions. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the existing butterfly valve technology that the valve stem expands under high temperature conditions, causing the valve core to shift axially with the valve stem, thereby affecting the sealing performance of the valve core, and thus providing a high temperature resistant butterfly valve.

[0006] To solve the above-mentioned technical problems, the present invention provides a high-temperature resistant butterfly valve, including a main valve stem extending into the valve body, a butterfly plate for sealing the medium passage fixedly connected to the main valve stem, and further comprising:

[0007] An upper valve stem is connected to the main valve stem, the upper valve stem and the main valve stem being connected to be circumferentially rotatable and axially movable relative to each other;

[0008] Elastic elements are respectively provided between the upper and lower ends of the butterfly plate and the valve body, and the butterfly plate is kept able to float up and down in the valve body by means of the elastic elements; there is a first accommodating space between the upper end of the main valve stem and the upper valve stem, and there is a second accommodating space between the lower end of the main valve stem and the valve body.

[0009] Optionally, the bottom end of the valve body is detachably connected to a flange, and the lower end of the butterfly plate abuts against the flange through a first elastic element, the first elastic element having an elastic force that drives the butterfly plate away from the flange at the bottom end of the valve body.

[0010] Optionally, a valve cover is connected to the valve body, and the upper valve stem is partially accommodated within the valve cover. An annular protrusion is constructed on the portion of the upper valve stem accommodated within the valve cover, and the radial dimension of the annular protrusion is larger than the diameter of the axial hole of the valve cover for extending the upper valve stem.

[0011] Optionally, the main valve stem and the upper valve stem are connected by a connector, and a keyway is provided on the inner wall of the connector to axially constrain the main valve stem and the upper valve stem, and the keyway is axially inserted through the connector.

[0012] Optionally, the connector has a limiting platform protruding from the inner wall of the connector, one side of the limiting platform abutting against the upper end of the main valve stem, and the first accommodating space is formed between the limiting platform and the lower end of the upper valve stem.

[0013] Optionally, a first gasket ring is provided between the first elastic element and the flange, and the first elastic element is limited to a first limiting groove opened in the valve body.

[0014] Optionally, the upper end of the butterfly plate is connected to the valve body through a second elastic element, and a second gasket is provided between the second elastic element and the valve cover. The second elastic element is limited to the second limiting groove opened in the valve body.

[0015] Optionally, the outer circumferential surface of the butterfly plate is provided with a sealing ring for sealing with the valve body, and the end of the sealing ring for sealing with the valve body is thinned.

[0016] Optionally, a pressure ring is detachably mounted on the butterfly plate, and an annular groove for mounting the sealing ring is formed between the outer circumferential surface of the butterfly plate and the pressure ring.

[0017] Optionally, a third accommodating space is provided between the inner ring of the sealing ring and the inner wall of the annular groove.

[0018] The technical solution of this invention has the following advantages:

[0019] 1. The high-temperature resistant butterfly valve provided by this invention is configured as a double-stem structure. The main stem is directly connected to the butterfly plate, and the upper stem is indirectly connected to the main stem. This reduces the overall size of the stem used to drive the butterfly plate to rotate. When the main stem expands and deforms axially due to heat, the distance the butterfly plate moves to one side is reduced, thereby improving the sealing performance between the butterfly plate and the valve seat. Specifically, firstly, when the length of the main stem is relatively reduced, the deformation caused by its thermal expansion is reduced, thus reducing the distance the butterfly plate moves. Secondly, when the distance difference between the two ends of the main stem extending on the butterfly plate is relatively reduced, when the main stem expands due to heat, the distance that the originally longer stem extends to one end can be distributed to both ends, so that the butterfly plate hardly shifts, thus ensuring the sealing performance between the butterfly plate and the valve seat.

[0020] In addition, the space reserved at both ends of the main valve stem can expand the heat dissipation space of the valve stem in the axial direction and enhance the overall heat dissipation effect of the valve body. By setting the butterfly plate to float up and down elastically in the valve body, and setting the first reserved space between the main valve stem and the upper valve stem, and the second reserved space between the main valve stem and the valve body, the valve body has a floating space to accommodate the axial expansion of the valve stem under high temperature conditions. During the axial expansion of the valve stem, the butterfly plate moves up and down elastically with the valve stem, which can also ensure a good sealing state, thus facilitating the normal operation of the butterfly valve.

[0021] 2. The high-temperature resistant butterfly valve provided by the present invention has the lower end of the butterfly plate abutting against the flange through a first elastic element. The first elastic element has an elastic force that drives the butterfly plate away from the flange at the bottom of the valve body. With this setting, when the butterfly plate shifts downward with the thermal expansion of the valve stem, it is subject to the limiting elastic force, which can prevent the butterfly plate from excessively shifting downward and affecting the normal sealing effect. In addition, the flange is detachably installed at the bottom of the valve body, which facilitates the assembly of other components in the valve body.

[0022] 3. The high-temperature resistant butterfly valve provided by the present invention enhances the installation stability of the upper valve stem in the valve cover by providing an annular protrusion on the upper valve stem portion located inside the valve cover. The radial dimension of the annular protrusion is larger than the diameter of the protrusion hole of the valve cover, thereby preventing the upper valve stem from being blown out of the valve cover by external force.

[0023] 4. The high-temperature resistant butterfly valve provided by the present invention uses a connector to connect the main valve stem and the upper valve stem, and the main valve stem and the upper valve stem are keyed to the connector, which can have better synchronous linkage rotation action to ensure the normal opening and closing action of the valve; and the method of constructing a limiting platform on the inner wall of the connector and moving the main valve stem against the limiting platform can reduce the wear of the key fit and extend the connection life of the connector between the main valve stem and the upper valve stem.

[0024] 5. The high-temperature resistant butterfly valve provided by the present invention has a first elastic element located in a first limiting groove opened in the valve body, and a second elastic element connected to the upper end of the butterfly plate. The second elastic element is located in a second limiting groove opened in the valve body, which is beneficial to enhancing the installation stability of the first elastic element and the second elastic element on the valve body.

[0025] 6. The high-temperature resistant butterfly valve provided by the present invention has a sealing ring circumferentially provided on the outer side of the butterfly plate. The end of the sealing ring used for sealing the valve body is thinned. This setting can increase the sealing specific pressure of the valve body and help extend the service life of the sealing ring.

[0026] 7. The high-temperature resistant butterfly valve provided by the present invention has a pressure ring detachably installed on the butterfly plate, and an annular groove for installing a sealing ring is formed between the pressure ring and the outer circumferential direction of the butterfly plate. This facilitates the assembly of the sealing ring on the butterfly plate. At the same time, the installation structure of the pressure ring and the annular groove can further enhance the limiting constraint of the sealing ring in the axial direction of the butterfly plate.

[0027] 8. The high-temperature resistant butterfly valve provided by the present invention has a third accommodating space between the inner ring of the sealing ring and the inner wall of the annular groove. With this arrangement, during the process of the butterfly plate floating up and down due to the thermal expansion of the valve stem, the sealing ring has elastic movement in the up and down direction within the annular groove, which helps to reduce the deformation of the sealing ring due to thermal expansion, so as to avoid affecting the normal sealing effect. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a cross-sectional view of the high-temperature resistant butterfly valve described in an embodiment of the present invention;

[0030] Figure 2 for Figure 1 Enlarged view of section A in the middle;

[0031] Figure 3 for Figure 1 Enlarged view of section B in the middle;

[0032] Figure 4 for Figure 1 Enlarged view of section C;

[0033] Figure 5 This is a schematic diagram of the connector according to an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Main valve stem; 2. Valve body; 3. Butterfly plate; 4. Upper valve stem; 5. Flange; 6. Connecting parts; 7. Valve cover;

[0036] 101. First storage space; 102. Second storage space; 103. Third storage space;

[0037] 201. First elastic element; 202. Second elastic element; 203. First washer; 204. First limiting groove; 205. Second washer; 206. Second limiting groove; 207. Limiting sleeve; 208. Bearing;

[0038] 301. Sealing ring; 302. Pressure ring; 303. Annular groove;

[0039] 401, Annular protrusion; 601, Keyway; 602, Limiting platform; 701, Heat sink. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] This embodiment specifically relates to a high-temperature resistant butterfly valve, which mainly includes a main valve stem 1, which extends into the valve body 2 and is fixedly connected to a butterfly plate 3 for blocking the medium passage. The high-temperature resistant butterfly valve also includes an upper valve stem 4 connected to the main valve stem 1. The upper valve stem 4 and the main valve stem 1 are connected to be able to rotate in a circumferential direction and to be able to move relative to each other in the axial direction.

[0045] In addition, elastic elements are respectively provided between the upper and lower ends of the butterfly plate 3 and the valve body 2, and the butterfly plate 3 is kept able to float up and down in the valve body 2 by means of the elastic elements; there is a first accommodating space 101 between the upper end of the main valve stem 1 and the upper valve stem 4, and there is a second accommodating space 102 between the lower end of the main valve stem 1 and the valve body 2.

[0046] Based on the above overall structural design, a specific implementation of the high-temperature resistant butterfly valve described in this embodiment is as follows: Figure 1 As shown, this embodiment uses a mature butterfly valve structure based on the triple eccentric principle. The connection between the handwheel and the valve stem of the butterfly valve can be achieved using an existing gearbox transmission. The butterfly valve should also have other mounting components that constitute the normal working state of the butterfly valve. These will not be specifically described in this embodiment.

[0047] In this embodiment, a valve cover 7 is connected to the valve body 2. The bottom end of the valve cover 7 is fastened to the valve body 2 by bolts. A high-temperature resistant gasket is placed at the joint between the valve cover 7 and the valve body 2 to ensure good sealing performance between the valve cover 7 and the valve body 2 under high-temperature conditions. The valve cover 7 extends upward along the length of the upper valve stem 4 so that part of the upper valve stem 4 is accommodated within the valve cover 7. The top end of the valve cover 7 is fastened to a mounting bracket for axially constraining the upper valve stem 4. Here, a mature existing packing seal structure is used between the mounting bracket and the end face of the valve cover 7 to ensure the sealing performance between the valve cover 7 and the bracket. A number of heat dissipation fins 701 can also be correspondingly constructed on the valve cover 7 to further facilitate heat dissipation of the valve body 2. Through the above arrangement, the installation gap between the main valve stem 1 and the upper valve stem 4 can be extended, which is beneficial to forming the aforementioned first accommodating space 101. At the same time, the extended valve cover 7 can further enhance the heat dissipation effect inside the valve body 2.

[0048] like Figure 1As shown, the portion of the upper valve stem 4 that is housed in the valve cover 7 has an annular protrusion 401. The radial dimension of the annular protrusion 401 is larger than the diameter of the shaft hole of the valve cover 7 for the upper valve stem 4 to extend out. The use of the annular protrusion 401 can eliminate the safety hazard of the upper valve stem 4 being pushed out of the valve cover 7 by the medium pressure or other external forces. In addition to using the annular protrusion 401, a limiting block constructed on the upper valve stem 4 can also be used, or a structure corresponding to the limiting of the upper valve stem 4 can be constructed at the end of the valve cover 7. As long as the upper valve stem 4 is limited to move upward in the opposite direction, it will be fine.

[0049] In this embodiment, the main valve stem 1 and the upper valve stem 4, located within the valve cover 7, are connected by a connector 6. Preferably, the connector 6 is a high-temperature resistant joint. A keyway 601 is provided on the inner wall of the connector 6 to axially constrain the main valve stem 1 and the upper valve stem 4. The keyway 601 axially penetrates the connector 6. Both the main valve stem 1 and the upper valve stem 4 are engaged within the connector 6 by a key, thereby achieving synchronous linkage between the main valve stem 1 and the upper valve stem 4. It should be noted that the engagement between the key on the main valve stem 1 and the keyway 601 is such that the keyway 601 abuts against the upper end of the key. This arrangement is to facilitate the movement of the connector 6 due to the thermal expansion of the main valve stem 1 under high-temperature conditions.

[0050] like Figure 5 As shown, based on the through keyway 601 structure, a limiting platform 602 protruding from the inner wall of the connector 6 is also constructed inside the connector 6. One side of the limiting platform 602 abuts against the upper end of the main valve stem 1, and the aforementioned first accommodating space 101 is formed between the limiting platform 602 and the lower end of the upper valve stem 4. Several limiting platforms 602 can be symmetrically arranged outward along the circumference of the connector 6 to achieve synchronous upward movement due to the push of the top of the main valve stem 1.

[0051] Here, the connector 6 can be a high-temperature resistant joint with a through keyway 601, or a sleeve with two spaced keyways 601, where the two keyways 601 on the sleeve respectively engage with the main valve stem 1 and the upper valve stem 4. As long as there is a certain fit tolerance—that is, the length of the keyway 601 is greater than the key length—relative movement between the main valve stem 1 and the upper valve stem 4 can be achieved. Compared to using a sleeve structure, using a high-temperature resistant joint can significantly reduce wear on the keyway and extend the connection life of the connector 6 between the main valve stem 1 and the upper valve stem 4.

[0052] In this embodiment, a flange 5 is detachably connected to the bottom end of the valve body 2. The lower end of the butterfly plate 3 abuts against the flange 5 via a first elastic element 201. The first elastic element 201 has an elastic force that drives the butterfly plate 3 away from the flange 5 at the bottom end of the valve body 2. The specific structure is as follows: Figure 4As shown, a first limiting groove 204 is constructed at one end of the valve body 2 corresponding to the flange 5, and a first gasket 203 is provided on the flange 5. The first elastic element 201 is constrained between the first limiting groove 204 and the first gasket 203. The butterfly plate 3 is provided with a bearing 208 and a limiting sleeve 207 in sequence downwards. The upper end of the first elastic element 201 is sleeved on the bottom end of the main valve stem 1 and is pressed against by the limiting sleeve 207, thereby achieving the limiting and blocking of the downward movement of the main valve stem 1 while ensuring the installation stability of the first elastic element 201.

[0053] In order to achieve the up-and-down floating motion of the butterfly plate 3 within the valve body 2, such as Figure 2 As shown, the upper end of the butterfly plate 3 is connected to the valve body 2 through the second elastic element 202. A second washer ring 205 is provided between the second elastic element 202 and the valve cover 7. The second elastic element 202 is constrained between the second limiting groove 206 and the second washer ring 205. A bearing 208 and a limiting sleeve 207 are arranged sequentially upward on the butterfly plate 3. The lower end of the second elastic element 202 is constrained in the second limiting groove 206 and is pressed against by the limiting sleeve 207. Here, the second elastic element 202 is used to form a limiting block for the upward movement of the main valve stem 1.

[0054] It should be noted that the first elastic element 201 and the second elastic element 202 are preferably disc springs. The aforementioned second accommodating space 102 is formed between the lower end of the main valve stem 1 and the flange 5. Preferably, the extension length of the upper end and the extension length of the lower end of the main valve stem 1 are symmetrically arranged about the horizontal center line of the main valve stem 1, so that the main valve stem 1 has the same tendency to expand axially to both ends under high temperature conditions. This is beneficial to the force balance of the first elastic element 201 and the second elastic element 202, thereby reducing the impact of excessive expansion of one end of the butterfly plate 3 on the normal sealing effect.

[0055] In this embodiment, as shown Figure 3 As shown, a sealing ring 301 for sealing and engaging with the valve body 2 is also provided on the outer circumferential side of the butterfly plate 3. The end of the sealing ring 301 for sealing and engaging with the valve body 2 is thinned. In a preferred embodiment, a pressure ring 302 is detachably mounted on the side of the butterfly plate 3 that abuts against the sealing surface of the valve body 2. An annular groove 303 for mounting the sealing ring 301 is formed between the pressure ring 302 and the outer circumferential side of the butterfly plate 3.

[0056] Here, the annular groove 303 serves to limit the sealing ring 301 from disengaging from the butterfly plate 3. The installation method between the pressure ring 302 and the butterfly plate 3 can be a bolt connection, thereby achieving a mechanical anti-loosening assembly effect. Specifically, the thinned sealing ring 301 can be constructed with a thinned portion extending from the butterfly plate 3. This design allows it to contact and seal with the conical sealing surface during the rotation and closure process of the butterfly plate 3, and minimizes the wear of the sealing ring 301 on the sealing surface.

[0057] Based on the structure using the pressure ring 302 for limiting, a third accommodating space 103 is provided between the inner ring of the sealing ring 301 and the inner wall of the annular groove 303. The specific range of this accommodating space should be such that when the sealing ring 301 is retracted into the accommodating space, at least a portion of its thinned part still extends outward from the butterfly plate 3. With this arrangement, when the sealing ring 301 is elastically compressed by the movement of the butterfly plate 3, part of it extends into the third accommodating space 103, which can further reduce the wear of the sealing ring 301 due to the up-and-down movement of the butterfly plate 3 under high-temperature conditions, thereby ensuring the normal sealing performance of the butterfly plate 3.

[0058] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A high-temperature resistant butterfly valve, comprising a main valve stem (1) extending into a valve body (2), wherein a butterfly plate (3) for sealing a medium passage is fixedly connected to the main valve stem (1), characterized in that, Also includes: The upper valve stem (4) is connected to the main valve stem (1), and the upper valve stem (4) and the main valve stem (1) are connected to be able to rotate in association in the circumferential direction, and the upper valve stem (4) and the main valve stem (1) are connected to be able to move relative to each other in the axial direction; Elastic elements are respectively provided between the upper and lower ends of the butterfly plate (3) and the valve body (2). Each elastic element of the butterfly plate (3) is provided with a bearing (208) and a limiting sleeve (207) in sequence. The elastic element is pressed against the limiting sleeve (207). The butterfly plate (3) is kept able to float up and down in the valve body (2) by means of the elastic elements. There is a first accommodating space (101) between the upper end of the main valve stem (1) and the upper valve stem (4). There is a second accommodating space (102) between the lower end of the main valve stem (1) and the valve body (2). The main valve stem (1) and the upper valve stem (4) are connected by a connector (6). A keyway (601) is provided on the inner wall of the connector (6) to axially constrain the main valve stem (1) and the upper valve stem (4). The keyway (601) is axially inserted through the connector (6). The connector (6) has a limiting platform (602) protruding from the inner wall of the connector (6). One side of the limiting platform (602) abuts against the upper end of the main valve stem (1). The first accommodating space (101) is formed between the limiting platform (602) and the lower end of the upper valve stem (4).

2. The high-temperature resistant butterfly valve according to claim 1, characterized in that, The bottom end of the valve body (2) is detachably connected to a flange (5). The lower end of the butterfly plate (3) is provided with the bearing (208) and the limiting sleeve (207) in sequence. The limiting sleeve (207) abuts against the flange (5) through a first elastic element (201). The first elastic element (201) has an elastic force that drives the butterfly plate (3) away from the flange (5) at the bottom end of the valve body (2).

3. The high-temperature resistant butterfly valve according to claim 1, characterized in that, The valve body (2) is connected to a valve cover (7), and the upper valve stem (4) is partially accommodated in the valve cover (7). An annular protrusion (401) is constructed on the portion of the upper valve stem (4) accommodated in the valve cover (7). The radial dimension of the annular protrusion (401) is larger than the diameter of the shaft hole of the valve cover (7) for extending the upper valve stem (4).

4. The high-temperature resistant butterfly valve according to claim 2, characterized in that, A first gasket (203) is provided between the first elastic element (201) and the flange (5), and the first elastic element (201) is limited to the first limiting groove (204) opened in the valve body (2).

5. The high-temperature resistant butterfly valve according to claim 3, characterized in that, The upper end of the butterfly plate (3) is provided with the bearing (208) and the limiting sleeve (207) in sequence. The limiting sleeve (207) is connected to the valve body (2) through the second elastic element (202). A second washer ring (205) is provided between the second elastic element (202) and the valve cover (7). The second elastic element (202) is limited in the second limiting groove (206) opened in the valve body (2).

6. The high-temperature resistant butterfly valve according to claim 1, characterized in that, The outer circumferential surface of the butterfly plate (3) is provided with a sealing ring (301) for sealing with the valve body (2), and the end of the sealing ring (301) for sealing with the valve body (2) is thinned.

7. The high-temperature resistant butterfly valve according to claim 6, characterized in that, A pressure ring (302) is detachably installed on the butterfly plate (3), and an annular groove (303) for installing the sealing ring (301) is formed between the outer circumferential direction of the butterfly plate (3) and the pressure ring (302).

8. The high-temperature resistant butterfly valve according to claim 7, characterized in that, There is a third accommodating space (103) between the inner ring of the sealing ring (301) and the inner wall of the annular groove (303).

Images