Top-mounted ball valve with self-sealing valve cover structure

Abstract

The utility model discloses a top-mounted ball valve with a self-sealing bonnet structure, which relates to the technical field of top-mounted ball valves and comprises a valve body, a self-sealing bonnet and a self-sealing component. A fluid channel is formed in the valve body, and an installation channel is formed in the top of the valve body and communicates with the fluid channel. The self-sealing valve cover is arranged in the mounting channel; the self-sealing assembly is arranged on the inner wall of the mounting channel, and the self-sealing assembly is used for sealing between the self-sealing valve deck and the mounting channel and preventing the self-sealing assembly from falling off from the end, away from the fluid channel, of the mounting channel. Middle flange connection of the top-mounted ball valve is changed into an internal pressure self-sealing valve cover connection structure, a self-sealing ring is arranged between the valve cover and the valve body, and a flange connection bolt in the valve does not bear medium pressure any more and only plays a role in structural connection. The flange joint of the valve is more reliable in sealing, and especially in high-temperature and high-pressure occasions, the higher the pressure of a medium in the valve is, the better the sealing performance is.

Description

Technical Field

[0001] The utility model relates to the technical field of top-entry ball valves, in particular to a top-entry ball valve with a self-sealing valve cover structure, which is particularly suitable for ball valves in the fields of petroleum and natural gas, especially high-temperature and high-pressure ball valves in the coal chemical industry. Background Art

[0002] As an efficient, low-carbon and clean fossil energy, natural gas has begun to replace primary energy sources such as coal and oil in many energy-using fields. It is an important bridge for the transition to a new energy system and a realistic choice for promoting energy transformation. The long-term growth trend of natural gas resource supply is expected to ensure the sustainable development of the natural gas industry. Among them, it has the advantages of easy transportation, diversified entities, strong flexibility, safety and efficiency.

[0003] At present, the existing top-loading ball valve adopts flange connection. For example, in the patents with publication numbers CN102094992A, CN102359618A and CN208816729U, a top-loading ball valve is disclosed respectively. The ball valve requires the valve stem to adopt an anti-flying out design. Usually, an anti-flying out shoulder is set on the valve cover to achieve the valve stem anti-flying out. The valve stem anti-flying out force acts on the middle flange connecting bolts of the ball valve through the valve cover. At the same time, the middle flange connecting bolts must also withstand the internal medium pressure of the valve. In high-temperature and high-pressure applications, the middle flange connecting bolts are loosened due to high-temperature temperature stress, reducing the preload force of the middle flange seal, resulting in the failure of the valve middle flange joint seal. On the other hand, under the action of the internal medium pressure of the valve, the middle mouth connecting bolts are subject to shear stress. When the internal medium pressure is an alternating operating condition, the middle flange bolts will also be affected by low-cycle fatigue, which will cause the middle flange connecting bolts to fail, thereby causing the middle flange sealing performance to decrease. Summary of the invention

[0004] In order to solve the technical problem that the middle flange connecting bolts of the existing top-entry ball valve fail due to shear stress and low-cycle fatigue factors, thereby causing the sealing performance of the middle flange to decrease, the utility model provides a top-entry ball valve with a self-sealing bonnet structure.

[0005] To achieve the above purpose, the utility model provides the following solutions:

[0006] The utility model provides a top-mounted ball valve with a self-sealing valve cover structure, comprising a valve body, a self-sealing valve cover and a self-sealing component; a fluid channel is arranged in the valve body, a mounting channel is arranged on the top of the valve body, and the mounting channel is communicated with the fluid channel; the self-sealing valve cover is arranged in the mounting channel; the self-sealing component is arranged on the inner wall of the mounting channel, and the self-sealing component is used for sealing between the self-sealing valve cover and the mounting channel and for preventing the self-sealing component from falling off from one end of the mounting channel away from the fluid channel.

[0007] Optionally, the self-sealing component includes a four-open ring and a self-sealing ring; a fixing groove is provided on the inner wall of the mounting channel; a valve cover guide surface is provided on the lower side wall of the self-sealing valve cover, and a limiting surface is provided in the middle and upper part of the valve cover guide surface; a limiting groove is provided on the lower part of the inner wall of the four-open ring; the four-open ring is arranged in the fixing groove, the limiting groove matches the limiting surface, and the self-sealing ring is arranged between the valve cover guide surface and the inner wall of the mounting channel.

[0008] Optionally, the valve cover guide surface includes an upper cylindrical surface and a lower conical surface; the lower diameter of the conical surface is larger than the upper diameter of the conical surface; and the shape of the self-sealing ring matches the space between the valve cover guide surface and the inner wall of the mounting channel.

[0009] Optionally, a restraining ring is arranged above the self-sealing valve cover; a groove is arranged at the bottom of the outer wall of the restraining ring, and the groove is used to match the top of the valve body; the top end face of the restraining ring is a reference surface for the restraining ring; a valve cover reference surface is arranged on the upper part of the self-sealing valve cover, and a limiting surface is arranged in the middle and upper part of the valve cover guide surface; a plurality of second studs are arranged on the limiting surface, and the bottom of the second studs is fixedly connected to the limiting surface; a plurality of restraining holes are axially arranged on the restraining ring, and the top of the second stud passes through the restraining hole and is threadedly connected with the second nut; the self-sealing valve cover is driven up and down by screwing the second nut, and when the valve cover reference surface is flush with the restraining ring reference surface, a good seal is formed on the valve pressure boundary.

[0010] Optionally, the four open rings include four annular parts, a process screw hole is provided in the middle of the annular parts; a through screw hole is provided on the inner hole surface of the fixing groove on the valve body, and the screw hole and the process screw hole are used to install the annular part into the fixing groove.

[0011] Optionally, the self-sealing assembly further includes a pressure plate; the pressure plate is arranged between the four open rings and the self-sealing ring.

[0012] Optionally, an O-ring is further provided between the self-sealing valve cover and the valve body, and the O-ring is located below the self-sealing ring.

[0013] Optionally, a bracket is provided above the valve body, and the bracket is used to install a driving device, and the driving device is used to drive the valve stem.

[0014] Compared with the prior art, the utility model has achieved the following technical effects:

[0015] (1) Compared with the existing top-entry ball valve, the force to prevent the valve stem from flying out is indirectly borne by the four-open ring instead of the connecting bolts in the middle of the valve, making the valve pressure boundary safer.

[0016] (2) Compared with the existing top-entry ball valve, the internal medium force of the valve is borne by the four open rings instead of the connecting bolts in the middle of the valve, making the valve pressure boundary safer.

[0017] (3) Compared with the existing top-entry ball valve, the valve flange joint seal is changed from the existing metal gasket to a flexible graphite non-metallic self-sealing ring, and its sealing performance is more reliable.

[0018] (4) Compared with the existing top-mounted ball valve, the self-sealing ring with a quantitative compression design has better sealing performance than the spiral wound gasket with a non-quantitative compression design. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a structural schematic diagram of a top-entry ball valve with a self-sealing valve cover structure in the utility model;

[0021] Figure 2 for Figure 1 A schematic diagram of the local enlarged structure at point A in the middle;

[0022] Figure 3 It is a structural schematic diagram of a valve body in a top-entry ball valve with a self-sealing valve cover structure in the utility model;

[0023] Figure 4 It is a structural schematic diagram of a self-sealing ring in a top-entry ball valve with a self-sealing bonnet structure in the utility model;

[0024] Figure 5 It is a structural schematic diagram of a valve cover in a top-entry ball valve with a self-sealing valve cover structure in the utility model;

[0025] Figure 6It is a structural schematic diagram of a check ring in a top-entry ball valve with a self-sealing bonnet structure in the utility model;

[0026] Figure 7 It is a structural front view of the four-open ring in the top-mounted ball valve with a self-sealing valve cover structure in the utility model.

[0027] Figure 8 for Figure 7 Top view of the .

[0028] Description of reference numerals:

[0029] 1. Valve body; 2. Valve stem; 3. Thrust washer; 4. Self-lubricating bearing; 5. Self-sealing valve cover; 6. Self-sealing ring; 7. Pressure plate; 8. Four open rings; 9. Check ring; 10. Bracket; 11. First stud; 12. First nut; 13. Second stud; 14. Second nut; 15. Third stud; 16. Third nut; 17. Packing pressure plate; 18. Packing sleeve; 19. Packing; 20. O-ring; 21. Fixing groove; 22. Inner hole surface; 23. Process hole; 24. Limiting groove; 25. Process screw hole; 26. Outer cylindrical surface; 27. Limiting surface; 28. Valve cover guide surface; 29. ​​Four open ring guide surface; 30. Valve cover reference surface; 31. Check ring reference surface; 32. Driving device. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] like Figures 1 to 8 As shown, this embodiment provides a top-mounted ball valve with a self-sealing valve cover structure, including a valve body 1, a self-sealing valve cover 5 and a self-sealing component; a fluid channel is arranged in the valve body 1, and a mounting channel is arranged on the top of the valve body 1, and the mounting channel is connected with the fluid channel; the self-sealing valve cover 5 is arranged in the mounting channel; the self-sealing component is arranged on the inner wall of the mounting channel, and the self-sealing component is used for sealing between the self-sealing valve cover 5 and the mounting channel and for preventing the self-sealing component from falling off from the end of the mounting channel away from the fluid channel.

[0032] In this specific embodiment, the self-sealing assembly includes a four-open ring 8, a pressure plate 7 and a self-sealing ring 6; a clamping groove 21 is provided on the inner wall of the installation channel; a valve cover guide surface 28 is provided on the lower side wall of the self-sealing valve cover 5, and a limited position surface 27 is provided in the middle and upper part of the valve cover guide surface 28; a limited position groove 24 is provided at the lower part of the inner wall of the four-open ring 8; the four-open ring 8 is arranged in the clamping groove 21, the limited position groove 24 matches the limited position surface 27, and the self-sealing ring 6 is arranged between the valve cover guide surface 28 and the inner wall of the installation channel. The pressure plate 7 is arranged between the four-open ring 8 and the self-sealing ring 6.

[0033] Four process holes 23 are evenly distributed at 360 degrees on the inner hole surface 22 of the fixing groove 21. The function of the process holes 23 is to fasten the process screw holes 25 on the four-open ring 8 with process screws. When disassembling the valve, the four-open ring 8 can also be pushed out through the process holes 23 using special tools to achieve the disassembly of the valve.

[0034] The valve cover guide surface 28 includes an upper cylindrical surface and a lower conical surface; the lower diameter of the conical surface is larger than the upper diameter of the conical surface; the shape of the self-sealing ring 6 matches the space between the valve cover guide surface 28 and the inner wall of the installation channel. Therefore, when the self-sealing valve cover 5 moves upward, the self-sealing ring 6 can be squeezed, so that the self-sealing ring 6 is deformed to form a good seal between the self-sealing valve cover 5 and the valve body 1.

[0035] The compression of the self-sealing ring 6 is (12±5)%, that is, the maximum allowable compression of the self-sealing ring 6 is 17%. Once the compression of the self-sealing ring 6 exceeds this value, the self-sealing ring 6 will be crushed and lose its sealing function. Considering that the valve is an angular stroke ball valve with a valve stem 2 that rotates 90 degrees, 70% of the allowable compression of the self-sealing ring 6 is taken as the sealing compression of the self-sealing ring 6, i.e., the limit size. The calculated value is 11.9%, which is adjusted to 12%. However, it is less than the allowable compression of the self-sealing ring 6 of 17%.

[0036] A check ring 9 is arranged above the self-sealing valve cover 5; a groove is arranged at the bottom of the outer wall of the check ring 9, and the groove is used to match the top of the valve body 1; the top end face of the check ring 9 is a check ring reference surface 31; a valve cover reference surface 30 is arranged on the upper part of the self-sealing valve cover 5, and a limiting surface 27 is arranged in the middle and upper part of the valve cover guide surface 28; a plurality of second studs 13 are arranged on the limiting surface 27, and the bottom of the second stud 13 is fixedly connected to the limiting surface 27; a plurality of check holes are arranged axially on the check ring 9, and the top of the second stud 13 passes through the check hole and is threadedly connected with a second nut 14; the self-sealing valve cover 5 is driven to move up and down by screwing the second nut 14, and when the valve cover reference surface 30 is flush with the check ring reference surface 31, the valve pressure boundary forms a good seal.

[0037] The four-open ring 8 includes four rings, and a process screw hole 25 is provided in the middle of the ring; a screw hole is provided through the inner hole surface 22 of the clamping groove 21 on the valve body 1, and the screw hole and the process screw hole 25 are used to install the ring into the clamping groove 21. The outer cylindrical surface 26 of the four-open ring 8 and the inner hole surface 22 of the clamping groove 21 of the valve body 1 are matched by the process screws, so that the self-sealing valve cover 5 is lifted to make the valve cover guide surface 28 and the four-open ring guide surface 29 of the four-open ring 8 match.

[0038] An O-ring 20 is further provided between the self-sealing valve cover 5 and the valve body 1 , and the O-ring 20 is located below the self-sealing ring 6 .

[0039] A bracket 10 is arranged above the valve body 1 , and the bracket 10 is used to install a driving device 28 , and the driving device 28 is used to drive the valve stem 2 .

[0040] When assembling the valve, after installing the valve ball and the valve stem 2, the self-sealing valve cover 5, the self-sealing ring 6, the pressure plate 7 and the four-open ring 8 are installed in sequence, and then the second bolt box check ring 9 is installed. The outer cylindrical surface 26 of the four-open ring 8 and the inner hole surface 22 of the clamping groove 21 of the valve body 1 are matched by the process screws, and the check ring 9 and the second nut 14 are further installed in sequence. Then, the second nut 14 is tightened in sequence in a diagonal clockwise order with a hydraulic fastener, driving the self-sealing valve cover 5, and the self-sealing ring 6 is compressed. When the valve cover reference surface 30 on the self-sealing valve cover 5 and the check ring reference surface 31 on the check ring 9 are in the same plane, it indicates that the limit surface 27 of the self-sealing valve cover 5 and the limit groove 24 of the four-open ring 8 are abutted. At this time, the compression rate of the self-sealing ring 6 is 12%, which is less than its allowable compression amount of 17%, and the valve pressure boundary forms a good seal.

[0041] In a more specific embodiment, the top-mounted ball valve structure of the self-sealing valve cover also includes a packing pressure plate 17, a packing sleeve 18 and a packing 19; the packing 19 is arranged between the self-sealing valve cover 5 and the valve stem 2, the lower part of the packing sleeve 18 extends between the self-sealing valve cover 5 and the valve stem 2, the upper part of the packing sleeve 18 cooperates with the bottom surface of the packing pressure plate 17, and the packing pressure plate 17 is installed on the top of the self-sealing valve cover 5 through the third stud 15 and the third nut 16. By tightening the third nut 16, the packing pressure plate 17 presses the packing sleeve 18 downward so that the packing 19 can seal the gap between the self-sealing valve cover 5 and the valve stem 2.

[0042] In a more specific embodiment, the valve body 1 and the bracket 10 are connected via a first stud 11 and a first nut 12 .

[0043] A thrust washer 3 and a self-lubricating bearing 4 are arranged between the bottom of the valve stem 2 and the self-sealing valve cover 5 .

[0044] The top-mounted ball valve with a self-sealing valve cover structure in the utility model solves the technical problem in the prior art that the middle flange connection bolts of the top-mounted ball valve become loose due to high temperature stress, which reduces the preload force of the middle flange seal and causes the valve middle flange joint to fail to seal. It also solves the technical problem that the middle flange connection bolts of the existing top-mounted ball valve fail due to shear stress and low-cycle fatigue factors, which leads to a decrease in the sealing performance of the middle flange. The middle flange connection of the top-mounted ball valve is changed to an internal pressure self-sealing valve cover connection structure, and a self-sealing ring is used between the valve cover and the valve body. The flange connection bolts in the valve are no longer subjected to the medium pressure, but only play a structural connection role. Another advantage of the internal pressure self-sealing valve cover is that the flange joint of the valve is more reliably sealed, especially in high temperature and high pressure situations. The higher the internal medium pressure of the valve, the better its sealing performance.

[0045] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, so it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure mark in the claims should not be regarded as limiting the claims involved.

[0046] This specification uses specific examples to illustrate the principles and implementation methods of the utility model. The above examples are only used to help understand the method and core idea of ​​the utility model. At the same time, for those skilled in the art, according to the idea of ​​the utility model, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the utility model.

Claims

1. A top-entry ball valve with a self-sealing bonnet structure, characterized in that: It comprises a valve body, a self-sealing valve cover and a self-sealing assembly; a fluid channel is arranged in the valve body, a mounting channel is arranged on the top of the valve body, and the mounting channel is communicated with the fluid channel; the self-sealing valve cover is arranged in the mounting channel; the self-sealing assembly is arranged on the inner wall of the mounting channel, and the self-sealing assembly is used for sealing between the self-sealing valve cover and the mounting channel and for preventing the self-sealing assembly from falling off from one end of the mounting channel away from the fluid channel; The self-sealing component includes four open rings and a self-sealing ring; a fixing groove is provided on the inner wall of the installation channel; a valve cover guide surface is provided on the lower side wall of the self-sealing valve cover, and a limiting surface is provided in the middle and upper part of the valve cover guide surface; a limiting groove is provided on the lower part of the inner wall of the four open ring; the four open ring is arranged in the fixing groove, the limiting groove matches the limiting surface, and the self-sealing ring is arranged between the valve cover guide surface and the inner wall of the installation channel.

2. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: The valve cover guide surface includes an upper cylindrical surface and a lower conical surface; the lower diameter of the conical surface is larger than the upper diameter of the conical surface; the shape of the self-sealing ring matches the space between the valve cover guide surface and the inner wall of the installation channel.

3. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: A check ring is arranged above the self-sealing valve cover; a groove is arranged at the bottom of the outer wall of the check ring, and the groove is used to match the top of the valve body; the top end face of the check ring is the check ring reference surface; a valve cover reference surface is arranged on the upper part of the self-sealing valve cover, and a limited position surface is arranged in the middle and upper part of the valve cover guide surface; a plurality of second studs are arranged on the limited position surface, and the bottom of the second studs is fixedly connected to the limited position surface; a plurality of check holes are arranged axially on the check ring, and the top of the second stud passes through the check hole and is threadedly connected with a second nut; the self-sealing valve cover is driven to move up and down by screwing the second nut, and when the valve cover reference surface is flush with the check ring reference surface, the valve pressure boundary forms a good seal.

4. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: The four-open ring includes four annular parts, and a process screw hole is arranged in the middle of the annular part; a screw hole is arranged on the valve body on the inner hole surface of the fixing groove, and the screw hole and the process screw hole are used to install the annular part into the fixing groove.

5. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: The self-sealing assembly further comprises a pressing plate; the pressing plate is arranged between the four-open ring and the self-sealing ring.

6. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: An O-ring is also arranged between the self-sealing valve cover and the valve body, and the O-ring is located below the self-sealing ring.

7. The top-entry ball valve with a self-sealing bonnet structure according to claim 1, characterized in that: A bracket is arranged above the valve body, and the bracket is used to install a driving device, and the driving device is used to drive the valve stem.

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