A ball valve sealing structure suitable for high-cleanliness medium

Abstract

The utility model relates to a ball valve sealing structure suitable for high clean medium, the pressure deformation groove is arranged on the outer circumferential surface of the plastic sealing element at an axial position, and the outer circumferential surface of the plastic sealing element at both sides of the pressure deformation groove forms a sealing lip surface in sealing cooperation with the inner wall of the valve body assembly. The pressure deformation groove reduces the contact area between the plastic sealing element and the inner wall of the valve body assembly, increases the contact specific pressure, reduces the rigidity of the plastic sealing element, and when the medium pressure acts on one side of the inner circumferential surface of the plastic sealing element, the pressure deformation groove is deformed under pressure, the medium pressure pushes the sealing lip to more closely adhere to the inner wall of the valve body assembly, forms a self-sealing characteristic with better sealing effect as the medium pressure rises, and realizes high sealing performance on the basis of ensuring low cost and low process precision requirement.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, specifically to a ball valve sealing structure suitable for high-cleanliness media. Background Technology

[0002] A ball valve is a valve in which the opening and closing element (ball) is driven by the valve stem and rotates around the valve axis. It can also be used for fluid regulation and control. Ball valves commonly use sealing elements to seal the sealing contact surfaces. Due to the defect of rubber and graphite materials in contaminating the medium, sealing elements made of rubber or graphite materials are usually prohibited for applications requiring high media cleanliness. Only sealing elements made of plastic materials such as PTFE and PPL are permitted.

[0003] However, plastic seals have high rigidity, and when subjected to force, the force is absorbed by the entire rigid structure, making it difficult to effectively transmit and convert it into specific pressure at the sealing contact surface. Furthermore, the rigid structure lacks the ability to compensate for pressure fluctuations in the medium, making leakage highly likely. While lip seals offer better sealing compensation performance, they are expensive and require advanced manufacturing processes. Therefore, there is an urgent need to design a ball valve sealing structure that is cost-effective, has low manufacturing requirements, and is suitable for high-cleanliness media. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a ball valve sealing structure suitable for high-cleanliness media.

[0005] The technical solution adopted by this utility model is as follows: A ball valve sealing structure suitable for high-cleanliness media includes a valve body assembly, a valve stem, and a ball. The valve body assembly has a flow channel for the medium to pass through. The valve stem drives the ball to rotate, thereby cutting off and connecting the flow channel. The valve body assembly has valve seats and valve seat pressure rings on both sides of the ball. The valve seats and the ball form a sealing fit. The valve seat pressure ring is located at the end of the valve seat away from the ball, and a first sealing groove is formed between the two. A plastic sealing element with a cross-sectional shape adapted to the first sealing groove is connected in the first sealing groove. The inner circumferential surface of the plastic seal is sealed to the outer circumferential surface of the valve seat. A pressure deformation groove is provided at an axial position on the outer circumferential surface of the plastic seal. The outer circumferential surfaces of the plastic seal located on both sides of the pressure deformation groove form sealing lips that seal to the inner wall of the valve body assembly.

[0006] Preferably, the first sealing groove has a trapezoidal cross-section, and its length at the end near the valve body assembly is greater than its length at the end near the valve seat.

[0007] Preferably, the cross-section of the pressure deformation groove is trapezoidal, and its length at the end near the valve body assembly is greater than its length at the end near the valve seat.

[0008] Preferably, the valve seat pressure ring has a plurality of mounting holes distributed around the valve seat on the end face away from the ball. A spring is provided in the mounting hole, and the two ends of the spring abut against the bottom of the mounting hole and the valve body assembly, respectively. The spring presses the valve seat pressure ring against the plastic seal.

[0009] Preferably, the outer periphery of the valve seat includes a first annular surface, a second conical surface, a third annular surface, and a fourth annular surface connected in sequence along the direction from near the sphere to away from the sphere. The diameter of the third annular surface is smaller than that of the first annular surface, and the diameter of the fourth annular surface is smaller than that of the third annular surface, forming a limiting step with it. The valve seat pressure ring has a central circular groove at one end near the ball, and the end face of this end surrounding the central circular groove forms an abutting cone surface. The first annular surface, the outer circumferential surface of the valve seat pressure ring, and the fourth annular surface are fitted and engaged with the inner wall of the valve body assembly. The central circular groove is adapted to the size of the third annular surface and forms a sliding fit, and the fourth annular surface is adapted to the size of the inner circumferential surface of the valve seat pressure ring and forms a sliding fit. The second conical surface, together with the abutting conical surface and the third annular surface, forms the first sealing groove.

[0010] Preferably, the fourth ring surface is provided with a second sealing groove, and the second sealing groove is provided with a plastic dustproof sealing ring that seals with the inner wall of the valve body assembly.

[0011] Preferably, the valve seat has a third sealing groove on the end face near the ball, and a plastic valve seat sealing ring that seals with the ball is provided in the third sealing groove.

[0012] Preferably, the valve body assembly includes a valve body and a valve cover, the flow channel is located inside the valve body, one end of the valve body has a first abutting part formed on its inner wall that abuts against the valve seat and valve seat pressure ring on that side, and the other end is connected to the valve cover through a threaded part, and the inner wall of the valve cover has a second abutting part formed on its inner wall that abuts against the valve seat and valve seat pressure ring on that side.

[0013] The beneficial effects of this utility model are as follows: The pressure deformation groove reduces the contact area between the plastic seal and the inner wall of the valve body assembly, thereby increasing the contact specific pressure and reducing the rigidity of the plastic seal. When the medium pressure acts on one side of the inner circumferential surface of the plastic seal, the pressure deformation groove is deformed under pressure, and the medium pressure pushes the sealing lip to adhere more tightly to the inner wall of the valve body assembly, forming a self-sealing characteristic with better sealing effect as the medium pressure increases. High sealing performance is achieved while ensuring low cost and low process precision requirements. 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 front sectional view of an embodiment of the present utility model; Figure 2 for Figure 1 Enlarged view of the structure at point A in the middle; Figure 3 for Figure 2 Enlarged view of the structure at point B in the middle; In the diagram, 1. Valve body; 2. Valve stem; 3. Ball; 4. Valve seat; 5. Valve seat pressure ring; 7. Valve cover; 31. Central circular groove; 32. Abutting conical surface; 41. First annular surface; 42. Second conical surface; 43. Third annular surface; 44. Fourth annular surface; 45. Limiting step; 51. Mounting hole groove; 52. Spring component; 61. First sealing groove; 62. Plastic seal; 71. Second abutting part; 101. First abutting part; 401. Third sealing groove; 402. Plastic valve seat sealing ring; 441. Second sealing groove; 442. Plastic dustproof sealing ring; 621. Pressure deformation groove; 622. Sealing lip surface. 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 3As shown in the figure, a ball valve sealing structure suitable for high-cleanliness media is provided in an embodiment of this utility model. It includes a valve body assembly, a valve stem 2, and a ball 3. The valve body assembly has a flow channel for the medium to pass through. The valve stem 2 drives the ball 3 to rotate, thus cutting off and connecting the flow channel. Valve seats 4 and valve seat pressure rings 5 ​​are provided on both sides of the ball 3 within the valve body assembly. The valve seats 4 and the ball 3 form a sealing fit. The valve seat pressure ring 5 is located at the end of the valve seat 4 away from the ball 3, and a first sealing groove 61 is formed between the two. A plastic sealing element 62 adapted to the cross-sectional shape of the first sealing groove 61 is connected inside the first sealing groove 61. The inner circumferential surface of the plastic seal 62 is sealed to the outer circumferential surface of the valve seat 4. A pressure deformation groove 621 is provided around the outer circumferential surface at an axial position. The outer circumferential surfaces of the plastic seal 62 on both sides of the pressure deformation groove 621 form a sealing lip surface 622 that seals to the inner wall of the valve body assembly.

[0020] This design reduces the contact area between the plastic seal and the inner wall of the valve body assembly, increasing the contact pressure and reducing the stiffness of the plastic seal. When the medium pressure acts on one side of the inner circumferential surface of the plastic seal, the pressure deformation groove deforms under pressure, and the medium pressure pushes the sealing lip to adhere more tightly to the inner wall of the valve body assembly, forming a self-sealing characteristic that improves the sealing effect as the medium pressure increases. This achieves high sealing performance while ensuring low cost and low process precision requirements.

[0021] Specifically, plastic seals refer to seals made of PTFE or PPL materials. The shape of the pressure deformation groove can be U-shaped, V-shaped, trapezoidal, or rectangular, etc.

[0022] The first sealing groove 61 has a trapezoidal cross section, and its length near the valve body assembly is greater than its length near the valve seat 4.

[0023] With this configuration, since the plastic seal is a trapezoid that matches the cross-sectional shape of the first sealing groove, when the medium pressure acts on one side of the inner circumferential surface of the plastic seal, part of the force distributed on the plastic seal will diffuse outward from the center, which helps to further reduce the rigidity of the plastic seal and enhance the self-sealing performance of this structure.

[0024] The cross-section of the pressure deformation groove 621 is trapezoidal, and its length at the end near the valve body assembly is greater than its length at the end near the valve seat 4.

[0025] By optimizing the cross-sectional shape, the pressure deformation groove can have a larger cavity area to further reduce the rigidity of the seal and the deformation compensation capability, so that the sealing lip can better fit the inner wall of the valve body assembly.

[0026] The valve seat pressure ring 5 has several mounting holes 51 distributed around the valve seat 4 on the end face away from the ball 3. A spring 52 is provided in the mounting hole 51. The two ends of the spring 52 abut against the bottom of the mounting hole 51 and the valve body assembly, respectively. The spring 52 presses the valve seat pressure ring 5 against the plastic seal 62.

[0027] This design ensures a tight seal between the valve seat pressure ring, valve seat, and plastic seal, further improving the sealing performance of the structure.

[0028] The outer periphery of the valve seat 4 includes a first annular surface 41, a second conical surface 42, a third annular surface 43, and a fourth annular surface 44 connected in sequence along the direction from near the ball 3 to away from the ball 3. The diameter of the third annular surface 43 is smaller than that of the first annular surface 41, and the diameter of the fourth annular surface 44 is smaller than that of the third annular surface 43, forming a limiting step 45 with it. The valve seat pressure ring 5 has a central circular groove 31 at one end near the ball 3, and the end face of this end surrounding the central circular groove 31 forms an abutting cone surface 32. The first annular surface 41, the outer peripheral surface of the valve seat pressure ring 5, and the fourth annular surface 44 are fitted together with the inner wall of the valve body assembly. The central circular groove 31 is sized to fit the third annular surface 43 and forms a sliding fit, and the fourth annular surface 44 is sized to fit the inner circumferential surface of the valve seat pressure ring 5 and forms a sliding fit. The second conical surface 42, together with the abutting conical surface 32 and the third annular surface 43, forms the first sealing groove 61.

[0029] This design ensures the sliding fit between the central groove and the third annular surface, and the sliding fit between the fourth annular surface and the inner circumferential surface of the valve seat pressure ring. This ensures the stability of the valve seat pressure ring moving on the valve seat when the spring is compressed and extended, and ensures that the two can maintain good concentricity during the operation of the ball valve. This, in turn, ensures the stability of the sealing fit between the second conical surface, the abutting conical surface and the plastic seal.

[0030] The fourth annular surface 44 is provided with a second sealing groove 441, and the second sealing groove 441 is provided with a plastic dustproof sealing ring 442 that seals with the inner wall of the valve body assembly.

[0031] This design effectively prevents dust from entering the valve body from the outside. The plastic dustproof seal specifically refers to a dustproof seal made of PTFE or PPL material.

[0032] The valve seat 4 is provided with a third sealing groove 401 on the end face near the ball 3, and a plastic valve seat sealing ring 402 is provided in the third sealing groove 401 to seal with the ball 3.

[0033] This design improves the stability of the valve seat's fit with the ball. Specifically, the plastic valve seat seal refers to a valve seat seal made of PTFE or PPL material.

[0034] The valve body assembly includes a valve body 1 and a valve cover 7. The flow channel is located inside the valve body 1. A first abutting part 101 is formed on the inner wall of one end of the valve body 1, which abuts and cooperates with the valve seat 4 and the valve seat pressure ring 5 on that side. The other end of the valve body 1 is connected to the valve cover 7 through a threaded part. A second abutting part 71 is formed on the inner wall of the valve cover 7, which abuts and cooperates with the valve seat 4 and the valve seat pressure ring 5 on that side.

[0035] This design allows for assembly by sequentially inserting each component into the valve body from the end where the valve body and valve cover mate, followed by installing the valve cover. This improves the ease of installation of the ball valve. Furthermore, the single-sided valve cover reduces installation leakage points compared to a double-sided valve cover, further enhancing the sealing safety of the device.

[0036] 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 ball valve sealing structure suitable for high-cleanliness media, comprising a valve body assembly, a valve stem (2), and a ball (3), wherein the valve body assembly has a flow channel for the medium to pass through, the valve stem (2) drives the ball (3) to rotate to cut off and connect the flow channel, and the valve body assembly has a valve seat (4) and a valve seat pressure ring (5) on both sides of the ball (3), wherein the valve seat (4) and the ball (3) form a sealing fit, characterized in that: The valve seat pressure ring (5) is located at the end of the valve seat (4) away from the ball (3) and a first sealing groove (61) is formed between the two. A plastic seal (62) adapted to its cross-sectional shape is connected in the first sealing groove (61). The inner circumferential surface of the plastic seal (62) is sealed to the outer circumferential surface of the valve seat (4), and a pressure deformation groove (621) is provided at an axial position on the outer circumferential surface. The outer circumferential surfaces of the plastic seal (62) on both sides of the pressure deformation groove (621) form a sealing lip (622) that seals to the inner wall of the valve body assembly.

2. The ball valve sealing structure suitable for high-cleanliness media according to claim 1, characterized in that: The first sealing groove (61) has a trapezoidal cross section, and its length near the valve body assembly is greater than its length near the valve seat (4).

3. The ball valve sealing structure suitable for high-cleanliness media according to claim 1, characterized in that: The cross-section of the pressure deformation groove (621) is trapezoidal, and its length near the valve body assembly is greater than its length near the valve seat (4).

4. The ball valve sealing structure suitable for high-cleanliness media according to claim 1, characterized in that: The valve seat pressure ring (5) has several mounting holes (51) distributed around the valve seat (4) on the end face away from the ball (3). A spring (52) is provided in the mounting hole (51). The two ends of the spring (52) abut against the bottom of the mounting hole (51) and the valve body assembly, respectively. The spring (52) presses the valve seat pressure ring (5) against the plastic seal (62).

5. A ball valve sealing structure suitable for high-cleanliness media according to claim 4, characterized in that: The outer periphery of the valve seat (4) includes a first annular surface (41), a second conical surface (42), a third annular surface (43), and a fourth annular surface (44) connected in sequence along the direction from near the ball (3) to away from the ball (3). The diameter of the third annular surface (43) is smaller than that of the first annular surface (41), and the diameter of the fourth annular surface (44) is smaller than that of the third annular surface (43) and forms a limiting step (45) with it. The valve seat pressure ring (5) has a central circular groove (31) at one end near the ball (3), and the end of the ring (5) surrounds the end face of the central circular groove (31) to form an abutting cone surface (32). The first annular surface (41), the outer circumferential surface of the valve seat pressure ring (5), and the fourth annular surface (44) are fitted together with the inner wall of the valve body assembly. The central circular groove (31) is adapted to the third annular surface (43) and forms a sliding fit, and the fourth annular surface (44) is adapted to the inner circumferential surface of the valve seat pressure ring (5) and forms a sliding fit. The second conical surface (42) forms the first sealing groove (61) with the abutting conical surface (32) and the third annular surface (43).

6. A ball valve sealing structure suitable for high-cleanliness media according to claim 5, characterized in that: The fourth annular surface (44) is provided with a second sealing groove (441), and the second sealing groove (441) is provided with a plastic dustproof sealing ring (442) that seals with the inner wall of the valve body assembly.

7. The ball valve sealing structure suitable for high-cleanliness media according to claim 1, characterized in that: The valve seat (4) has a third sealing groove (401) on the end face near the ball (3), and a plastic valve seat sealing ring (402) is provided in the third sealing groove (401) to seal with the ball (3).

8. A ball valve sealing structure suitable for high-cleanliness media according to any one of claims 1-7, characterized in that: The valve body assembly includes a valve body (1) and a valve cover (7). The flow channel is located inside the valve body (1). The inner wall of one end of the valve body (1) forms a first abutting part (101) that abuts against the valve seat (4) and the valve seat pressure ring (5) on that side. The other end of the valve body (1) is connected to the valve cover (7) through a threaded part. The inner wall of the valve cover (7) forms a second abutting part (71) that abuts against the valve seat (4) and the valve seat pressure ring (5) on that side.

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