An upper-mounted ultra-low temperature eccentric half-ball valve

Abstract

The utility model relates to valve technical field especially is related to a kind of upper-mounted ultra-low temperature eccentric half-ball valve, including valve body, valve cover, valve seat, ball and valve stem, the valve cover is installed in one end of valve body, the valve seat is arranged inside valve body, the ball is rotated and is arranged inside valve body for sealing cooperation with valve seat by valve stem, still include bellows and pressing plate ring, the pressing plate ring is arranged in one side of valve seat and is abutted on the inner wall of valve body, the bellows one end is connected valve seat and other end is connected pressing plate ring, first hard alloy sealing surface is equipped on the pressing plate ring, second hard alloy sealing surface is equipped on the inner wall of valve body and is combined with first hard alloy sealing surface, double-lip sealing ring is also clamped between the valve seat and valve body, the utility model is provided with three seals between valve seat and valve body, improve the sealing performance between valve seat and valve body, reliable sealing can also be maintained for long-term use.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, and in particular to a top-mounted cryogenic eccentric hemispherical valve. Background Technology

[0002] The eccentric hemispherical valve is a relatively new type of ball valve. It possesses unique structural advantages, such as frictionless switching, wear-resistant seals, and low opening and closing torque. This allows for smaller actuators, and when paired with a multi-turn electric actuator, it can achieve both medium regulation and tight shut-off. It is widely applicable in applications requiring strict shut-off, such as petroleum, chemical, and urban water supply and drainage systems. To adapt to low-temperature conditions, a top-loading cryogenic eccentric hemispherical valve has been designed.

[0003] Existing top-mounted cryogenic eccentric hemispherical valves have a short service life under low-temperature conditions. The internal seals gradually lose their compensating ability due to changes in elastic modulus in low-temperature environments, and are prone to sealing failure after long-term use. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a top-mounted cryogenic eccentric hemispherical valve. This invention sets three seals between the valve seat and the valve body, which improves the sealing performance between the valve seat and the valve body and can maintain a reliable seal even after long-term use.

[0005] The technical solution adopted by this utility model is as follows: A top-mounted ultra-low temperature eccentric hemispherical valve includes a valve body, a valve cover, a valve seat, a ball, and a valve stem. The valve cover is installed at one end of the valve body, the valve seat is disposed inside the valve body, and the ball is rotatably disposed inside the valve body via the valve stem for sealing cooperation with the valve seat. It also includes a bellows and a pressure plate ring. The pressure plate ring is disposed on one side of the valve seat to abut the valve seat against the inner wall of the valve body. One end of the bellows is connected to the valve seat and the other end is connected to the pressure plate ring. The pressure plate ring is provided with a first hard alloy sealing surface, and the inner wall of the valve body is provided with a second hard alloy sealing surface that fits against the first hard alloy sealing surface. A double-lip sealing ring is also sandwiched between the valve seat and the valve body.

[0006] The valve seat is also fitted with a valve seat sealing ring that seals with the ball. The valve seat sealing ring has lip-shaped sealing rings on both the inner and outer edges of the side into which it is embedded.

[0007] The pressure plate ring is threaded to the inner wall of the valve body and also includes a locking screw, which is screwed into the valve body and the pressure plate ring in a radial direction.

[0008] The valve body is also provided with an L-shaped cavity channel, one end of which extends to the valve seat and the other end extends to the outside of the valve body. An inflation port is provided on the outer wall of the valve body at the opening of the L-shaped cavity channel.

[0009] A pressure self-sealing assembly is provided between the valve cover and the valve body. The pressure self-sealing assembly includes a spring, a spring seat, at least two sets of triangular combined sealing rings, and at least one set of flat gaskets arranged along the valve stem axial direction. The flat gaskets are sandwiched between the two sets of triangular combined sealing rings. The springs press the spring seat toward the triangular combined sealing rings. The valve cover extends with a flange, which is connected to the valve body by flange bolts. The flange has a first hard alloy surface, and the valve body has a second hard alloy surface that fits against the first hard alloy surface.

[0010] The valve stem passes through the ball, and the valve stem is provided with at least two connecting sections that connect and cooperate with the ball. Each of the two connecting sections includes several semi-circular bosses that are spaced apart around the outer peripheral wall of the valve stem. One of the connecting sections abuts against the valve cover, and the other connecting section abuts against the valve body. A valve stem bearing is also sandwiched between the valve stem and the valve cover.

[0011] An eccentricity is provided between the centerline of the valve stem and the centerline of the valve body, and an eccentric angle is provided between the ball and the sealing surface of the valve seat. The ball is also provided with a wedge-shaped angle that mates with the sealing surface of the valve seat.

[0012] The ball is provided with an upper journal that mates with the valve cover and a lower journal that mates with the valve body. An upper ball bearing is also sandwiched between the upper journal and the valve cover, and a lower ball bearing is also sandwiched between the lower journal and the valve body. A sliding washer is also sandwiched between the lower journal and the end face of the valve body in the corresponding axial direction.

[0013] The beneficial effects of this utility model are as follows: This utility model sets three seals between the valve seat and the valve body, and with the addition of a pressure plate ring to prevent lateral displacement of the valve seat, the sealing performance between the valve seat and the valve body is improved. The first seal is a metal-to-metal seal between the first hard alloy sealing surface on the pressure plate ring and the second hard alloy sealing surface on the inner wall of the valve body. The double-sided hard alloy sealing surfaces are overlaid and ground to Ra0.1 micrometers to prevent the medium from leaking from the large step plane of the valve seat to the downstream end. The second seal is a bellows that is sealed between the pressure plate ring and the valve body to prevent the medium from leaking from the outer diameter of the valve seat to the downstream end. The third seal is a double-lip sealing ring set between the valve seat and the valve body to prevent the medium from leaking from the outer diameter of the valve seat piston to the downstream end. Reliable sealing can be maintained even after long-term use, extending the service life of the top-mounted ultra-low temperature eccentric hemispherical valve under low temperature conditions. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0015] Figure 1 This is a cross-sectional view of the present invention; Figure 2 for Figure 1 A magnified view of a portion of point A in the middle; Figure 3 for Figure 1 A magnified view of a portion of point B in the middle; Figure 4 for Figure 1 A magnified view of a portion of point C in the middle; Figure 5 for Figure 1 A magnified view of a portion of point D in the middle; Figure 6 for Figure 1 A magnified view of a portion of point E in the middle; Figure 7 This is a cross-sectional view of the valve stem and ball mating point in this utility model; Figure 8 This is a cross-sectional view of the valve seat and the ball mating point in this utility model; In the diagram, 1-valve body, 2-valve cover, 3-valve seat, 4-ball, 5-valve stem, 6-bellows, 7-pressure plate ring, 8-first hard alloy sealing surface, 9-second hard alloy sealing surface, 10-double lip seal ring, 11-valve seat seal ring, 12-lip seal ring, 13-locking screw, 14-L-shaped cavity channel, 15-inflation port, 16-spring, 17-spring seat, 18-triangular combination seal ring, 19-flat washer, 20-flange, 21-flange bolt, 22-first hard alloy surface, 23-second hard alloy surface, 24-semi-circular boss, 25-valve stem bearing, 26-eccentricity, 27-eccentricity angle, 28-wedge angle, 29-upper journal, 30-lower journal, 31-upper ball journal bearing, 32-lower ball journal bearing, 33-sliding washer. Detailed Implementation

[0016] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0017] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.

[0018] The directional and positional terms used in this utility model, such as "up," "down," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side," are merely for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0019] like Figures 1 to 8 As shown in the figure, an embodiment of the present invention is disclosed, comprising a top-mounted cryogenic eccentric hemispherical valve, including a valve body 1, a valve cover 2, a valve seat 3, a ball 4, and a valve stem 5. The valve cover 2 is installed at one end of the valve body 1, the valve seat 3 is disposed inside the valve body 1, and the ball 4 is rotatably disposed inside the valve body 1 via the valve stem 5 for sealing cooperation with the valve seat 3. The valve body 1 also includes a bellows 6 and a pressure plate ring 7. The pressure plate ring 7 is disposed on one side of the valve seat 3, abutting the valve seat 3 against the inner wall of the valve body 1. One end of the bellows 6 is connected to the valve seat 3, and the other end is connected to the pressure plate ring 7. The pressure plate ring 7 is provided with a first hard alloy sealing surface 8, and the inner wall of the valve body 1 is provided with a second hard alloy sealing surface 9 that fits against the first hard alloy sealing surface 8. A double-lip sealing ring 10 is also sandwiched between the valve seat 3 and the valve body 1.

[0020] The beneficial effects of this design are as follows: This utility model sets up three seals between the valve seat and the valve body, and with the addition of a pressure plate ring to prevent lateral displacement of the valve seat, the sealing performance between the valve seat and the valve body is improved. The first seal is a metal-to-metal seal between the first hard alloy sealing surface on the pressure plate ring and the second hard alloy sealing surface on the inner wall of the valve body. The double-sided hard alloy sealing surfaces are overlaid with welding and ground to Ra0.1 micrometers, preventing the medium from leaking from the large step plane of the valve seat to the downstream end. The second seal is a bellows fitted between the pressure plate ring and the valve body, preventing the medium from leaking from the outer diameter of the valve seat to the downstream end. The third seal is a double-lip sealing ring between the valve seat and the valve body, preventing the medium from leaking from the outer diameter of the valve seat piston to the downstream end. Reliable sealing is maintained even after long-term use, extending the service life of the top-mounted cryogenic eccentric hemispherical valve under low-temperature conditions. During assembly, the pressure plate ring is first fitted onto the valve seat, and then the first hard alloy sealing surface is welded onto the pressure plate ring. The bellows is installed between the inner wall of the valve body and the first hard alloy sealing surface.

[0021] Furthermore, the valve seat 3 is also fitted with a valve seat sealing ring 11 that seals with the ball 4. The valve seat sealing ring 11 is fitted with lip-shaped sealing rings 12 on both the inner and outer edges of the side of the valve seat 3.

[0022] The advantages of this design are as follows: an independent valve seat seal ring is installed on the valve seat for sealing and mating with the ball; the split structure allows for individual replacement of the valve seat seal ring, facilitating later maintenance; and two lip seal rings are installed on one side of the valve seat seal ring to prevent media leakage from the outer diameter of the valve seat seal ring.

[0023] Furthermore, the pressure plate ring 7 is threadedly connected to the inner wall of the valve body 1, and also includes a locking screw 13, which is screwed into the valve body 1 and the pressure plate ring 7 in a radial direction.

[0024] The advantages of this design are as follows: the pressure plate ring is fixed to the valve body by threads, and a locking screw is provided to prevent the threads from loosening. The pressure plate ring is not only easy to disassemble and assemble, but also securely installed.

[0025] Furthermore, the valve body 1 is provided with an L-shaped cavity channel 14, one end of which extends to the valve seat 3 and the other end extends to the outside of the valve body 1. An inflation port 15 is provided on the outer wall of the valve body 1 at the opening of the L-shaped cavity channel 14.

[0026] The beneficial effects of this design are as follows: when the top-mounted cryogenic eccentric hemispherical valve has been used for a period of time and the valve seat is not sealed tightly, air pressure can be injected into the L-shaped cavity channel of the valve body through the external air inlet, pushing the valve seat to move towards the ball, so that the valve seat is tightly attached to the ball, generating a sealing pressure, thereby ensuring the sealing of the valve seat sealing ring and the ball, preventing internal leakage. The air inlet has a self-sealing ability and can block the L-shaped cavity channel when not inflated.

[0027] Further, a pressure self-sealing assembly is provided between the valve cover 2 and the valve body 1. The pressure self-sealing assembly includes a spring 16, a spring seat 17, at least two sets of triangular combined sealing rings 18, and at least one set of flat gaskets 19 arranged axially along the valve stem 5. The flat gaskets 19 are sandwiched between the two sets of triangular combined sealing rings 18. The spring 16 presses the spring seat 17 toward the triangular combined sealing rings 18. The valve cover 2 extends with a flange 20. The flange 20 is connected to the valve body 1 by flange bolts 21. The flange 20 is provided with a first hard alloy surface 22. The valve body 1 is provided with a second hard alloy surface 23 that fits against the first hard alloy surface 22.

[0028] The beneficial effects of this design are as follows: The flange seal employs a dual sealing structure of pressure self-sealing and planar metal-to-metal sealing. The pressure self-sealing structure consists of a spring seat, a spring, a triangular combination sealing ring, and a flat gasket. Several sets of triangular combination sealing rings can be used, with a flat gasket sandwiched between every two sets. Under low pressure, the preload provided by the spring compresses the triangular combination sealing ring, ensuring a seal; under high pressure, the pressure of the medium itself pushes the spring seat to compress the triangular combination sealing ring, ensuring a seal. The planar metal-to-metal seal, i.e., the first hard alloy surface on the flange and the second hard alloy surface on the valve body, uses a double-sided hard alloy planar structure with overlay welding. The surfaces are ground to Ra 0.1 micrometers and then tightened with flange bolts to ensure a seal.

[0029] Further, the valve stem 5 penetrates the ball 4, and the valve stem 5 is provided with at least two connecting sections that connect and cooperate with the ball 4. Each of the two connecting sections includes a plurality of semi-circular bosses 24 spaced around the outer peripheral wall of the valve stem 5. One of the connecting sections abuts against the valve cover 2, and the other connecting section abuts against the valve body 1. A valve stem bearing 25 is also sandwiched between the valve stem 5 and the valve cover 2.

[0030] The beneficial effects of this design are as follows: The valve stem adopts a through-body design, with the upper and lower sections being a single unit, improving the coaxiality of the valve stem and the ball; ensuring that the ball and the valve seat sealing surface are evenly fitted together when the valve is opened or closed, preventing damage to the valve seat sealing surface caused by misalignment during operation. The valve stem has upper and lower semi-circular bosses that mate with the ball, improving the torsional and compressive strength of the valve stem head. The upper semi-circular boss is abutted and limited within the valve body by the valve cover, preventing the valve stem from flying out in the event of abnormal pressure rise in the valve cavity. The valve stem bearing ensures smooth valve stem rotation.

[0031] Further, an eccentricity of 26 is provided between the centerline of the valve stem 5 and the centerline of the valve body 1, an eccentric angle of 27 is provided between the sealing surface of the ball 4 and the valve seat 3, and a wedge angle of 28 is provided on the ball 4 to cooperate with the sealing surface of the valve seat 3.

[0032] The beneficial effects of this design are as follows: the double eccentric structure design has two main aspects. The first eccentricity is the vertical displacement eccentricity between the valve stem and the valve body, which ensures that there is no friction or jamming between the ball and the valve seat during valve opening, resulting in low opening and closing torque and improved valve service life. The second eccentricity is the angular eccentricity between the ball and the valve seat sealing surface. When the valve is closed, the ball and the valve seat sealing surface have a wedge-shaped angle, which tightens as the valve is closed, improving the valve seat sealing effect.

[0033] Furthermore, the ball 4 is provided with an upper journal 29 that mates with the valve cover 2 and a lower journal 30 that mates with the valve body 1. An upper ball bearing 31 is also sandwiched between the upper journal 29 and the valve cover 2, and a lower ball bearing 32 is also sandwiched between the lower journal 30 and the valve body 1. A sliding washer 33 is also sandwiched between the lower journal 30 and the corresponding axial end face of the valve body 1.

[0034] The beneficial effects of this design are as follows: the upper and lower journals of the ball are equipped with sliding bearings, the lower journal is positioned in the valve body, and the upper journal is positioned in the valve cover. This effectively transfers the medium pressure to the valve body and valve cover, so that the valve stem only bears the valve opening and closing torque and does not bear the lateral bending force, thereby changing the stress condition of the valve stem, improving its service life, and reducing wear between the lower journal and the inner wall of the valve body through the sliding shim.

[0035] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A top-mounted cryogenic eccentric hemispherical valve, comprising a valve body (1), a valve cover (2), a valve seat (3), a ball (4), and a valve stem (5), wherein the valve cover (2) is installed at one end of the valve body (1), the valve seat (3) is disposed inside the valve body (1), and the ball (4) is rotatably disposed inside the valve body (1) via the valve stem (5) for sealing cooperation with the valve seat (3), characterized in that: It also includes a bellows (6) and a pressure plate ring (7). The pressure plate ring (7) is set on one side of the valve seat (3) to abut the valve seat (3) against the inner wall of the valve body (1). One end of the bellows (6) is connected to the valve seat (3) and the other end is connected to the pressure plate ring (7). The pressure plate ring (7) is provided with a first hard alloy sealing surface (8). The inner wall of the valve body (1) is provided with a second hard alloy sealing surface (9) that fits against the first hard alloy sealing surface (8). A double lip sealing ring (10) is also sandwiched between the valve seat (3) and the valve body (1).

2. The top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: The valve seat (3) is also fitted with a valve seat sealing ring (11) that seals with the ball (4). The valve seat sealing ring (11) is fitted with a lip-shaped sealing ring (12) on the inner edge and outer edge of the side of the valve seat (3).

3. The top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: The pressure plate ring (7) is threaded to the inner wall of the valve body (1) and also includes a locking screw (13), which is screwed into the valve body (1) and the pressure plate ring (7) in a radial direction.

4. The top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: The valve body (1) is also provided with an L-shaped cavity channel (14), one end of which extends to the valve seat (3) and the other end extends to the outside of the valve body (1). The outer wall of the valve body (1) is provided with an inflation port (15) corresponding to the opening of the L-shaped cavity channel (14).

5. The top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: A pressure self-sealing assembly is provided between the valve cover (2) and the valve body (1). The pressure self-sealing assembly includes a spring (16) arranged along the axial direction of the valve stem (5), a spring seat (17), at least two sets of triangular combination sealing rings (18), and at least one set of flat gaskets (19). The flat gaskets (19) are sandwiched between the two sets of triangular combination sealing rings (18). The spring (16) presses the spring seat (17) toward the triangular combination sealing rings (18). The valve cover (2) extends with a flange (20). The flange (20) is connected to the valve body (1) by flange bolts (21). The flange (20) is provided with a first hard alloy surface (22). The valve body (1) is provided with a second hard alloy surface (23) that fits against the first hard alloy surface (22).

6. The top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: The valve stem (5) passes through the ball (4), and the valve stem (5) is provided with at least two connecting sections that connect and cooperate with the ball (4). Each of the two connecting sections includes several semi-circular bosses (24) distributed at intervals around the outer peripheral wall of the valve stem (5). One of the connecting sections abuts against the valve cover (2), and the other connecting section abuts against the valve body (1). A valve stem bearing (25) is also sandwiched between the valve stem (5) and the valve cover (2).

7. A top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: An eccentricity (26) is provided between the centerline of the valve stem (5) and the centerline of the valve body (1), and an eccentric angle (27) is provided between the sealing surface of the ball (4) and the valve seat (3), and a wedge angle (28) is provided on the ball (4) to cooperate with the sealing surface of the valve seat (3).

8. A top-mounted cryogenic eccentric hemispherical valve according to claim 1, characterized in that: The ball (4) is provided with an upper journal (29) that cooperates with the valve cover (2) and a lower journal (30) that cooperates with the valve body (1). An upper ball bearing (31) is also provided between the upper journal (29) and the valve cover (2), and a lower ball bearing (32) is also provided between the lower journal (30) and the valve body (1). A sliding washer (33) is also provided between the lower journal (30) and the end face of the valve body (1) in the corresponding axial direction.

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