A self-balancing floating ball valve

Abstract

This utility model belongs to the field of ball valves, and in particular to a self-balancing floating ball valve. It addresses the problem that existing floating ball valves achieve sealing through line contact between the ball and the valve seat, but under high-pressure conditions, the contact pressure between the ball and the valve seat increases significantly, leading to a sharp increase in frictional torque during valve opening and closing, requiring large actuators or manual application of significant operating force. The proposed solution includes a valve body with an open top; a valve cover fixedly mounted on the top of the valve body via an mounting assembly; a valve stem that rotatably passes through the valve cover; and a ball located inside the valve body, slidably connected to the valve stem via a slider and slide rail structure, allowing the ball to float axially along the valve stem. In this utility model, the slider-slide rail structure achieves the sliding connection between the ball and the valve stem, and with the help of fluid pressure or spring action, the ball floats slightly towards the low-pressure side (upstream) at the moment of opening, forming a non-contact sealing state.

Description

Technical Field

[0001] This utility model relates to the field of ball valve technology, and in particular to a self-balancing floating ball valve. Background Technology

[0002] Ball valves, as a common fluid control device, are widely used in petroleum, chemical, and power industries. Traditional floating ball valves achieve sealing through line contact between the ball and the valve seat. However, under high-pressure conditions, the contact pressure between the ball and the valve seat increases significantly, leading to a sharp increase in frictional torque during valve opening and closing. This requires a large actuator or manual application of significant operating force, which not only increases equipment costs but also easily causes wear on the sealing surface or actuator failure due to excessive operating torque. Furthermore, there is a lack of integrated design for dynamic adjustment of spring pressure and rapid maintenance functions. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing floating ball valves, which achieve sealing through line contact between the ball and the valve seat. However, under high-pressure conditions, the contact pressure between the ball and the valve seat increases significantly, leading to a sharp increase in frictional torque when the valve is opened and closed. This requires the use of large actuators or manual application of large operating forces, which not only increases equipment costs but also easily causes wear on the sealing surface or failure of the actuator due to excessive operating torque. Therefore, a self-balancing floating ball valve is proposed.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A self-balancing floating ball valve includes a valve body, wherein the top of the valve body is an opening.

[0006] The valve cover is fixedly mounted to the top of the valve body using mounting components.

[0007] The valve stem rotates through the valve cover;

[0008] A ball, located inside the valve body, is slidably connected to the valve stem via a slider and slide rail structure, allowing the ball to float axially along the valve stem. A handle is fixedly mounted on the top of the valve stem by a second internal hex bolt.

[0009] A sealing assembly, disposed inside the valve body, includes a valve seat for forming a seal with the ball;

[0010] The adjustment assembly includes a compression spring and an adjustment mechanism, wherein the compression spring acts on a ball and the adjustment mechanism is used to adjust the preload of the compression spring;

[0011] When the valve is opened, the fluid pressure causes the ball to float upstream, reducing the contact pressure between the ball and the valve seat, thereby reducing the starting torque.

[0012] In one possible design, the mounting assembly includes a plurality of mounting bolts fixed to the top of the valve body and threaded with nuts to secure the valve cover, with a gasket provided between the valve cover and the valve body.

[0013] In one possible design, the sealing assembly further includes a sealing ring disposed between the valve seat and the valve body to enhance the seal.

[0014] In one possible design, the adjustment assembly includes a fixed outer sheath fixedly fitted onto the valve stem, an annular pressure plate slidably disposed within the annular groove of the fixed outer sheath, and a compression spring fitted onto the outside of the valve stem, with one end abutting against the annular pressure plate and the other end abutting against a ball.

[0015] In one possible design, the adjustment mechanism includes an adjustment bolt threaded through a relief groove in the fixed outer sheath and rotatably connected to an annular pressure plate; wherein rotating the adjustment bolt drives the annular pressure plate to move to adjust the compression of the compression spring.

[0016] In one possible design, the packing body is located inside the valve cover, and the packing gland is fixed to the valve cover by bolts to seal the valve stem.

[0017] In one possible design, an antistatic spring is also included, embedded inside the valve stem, connecting the ball and the valve stem, for dissipating static electricity.

[0018] In one possible design, the adjusting bolt is rotatably connected to the annular pressure plate via a thrust bearing, thereby achieving stepless adjustment of the spring preload.

[0019] In this application, during use, rotating the handle causes the valve stem to rotate, which in turn rotates the ball, thereby changing the valve's opening and closing state and controlling fluid flow. After the ball moves up and down, at the moment the valve opens or under pressure equilibrium, the ball can slightly "float" or "lift" upstream from the downstream valve seat under fluid pressure (or with the help of a spring or other structure). This significantly reduces the contact pressure between the ball and the valve seat, thus significantly reducing the starting and operating torque required to rotate the ball. This makes the valve easier to operate, allowing for the use of smaller actuators and reducing operating force.

[0020] In practical use, the pressure of the compression spring can also be adjusted. Specifically, by unscrewing the nut and mounting bolt, the valve cover can be removed from the top, and the ball can be removed from the top. After removal, the internal packing body can be replaced. The height of the annular pressure plate can also be adjusted by turning the adjusting bolt. After the annular pressure plate moves up and down along the annular groove, the compression degree of the compression spring can be changed, its pressure can be adjusted, and the applicable range of the device can be expanded.

[0021] Beneficial effects:

[0022] This application achieves a sliding connection between the ball and the valve stem through a slider-rail structure. Combined with fluid pressure or spring action, the ball slightly floats towards the low-pressure side (upstream) at the moment of opening, forming a non-contact sealing state. This design transforms traditional line contact sealing into dynamic surface contact sealing, allowing direct use of small electric / pneumatic actuators while extending the service life of the sealing surface.

[0023] The compression of the spring can be steplessly adjusted (with an adjustment accuracy of 0.1mm) via the threaded transmission mechanism between the adjusting bolt and the annular pressure plate. This structure allows for dynamic adjustment of the spring preload based on medium pressure (0-10MPa) or temperature changes (-20℃~200℃), ensuring that the valve maintains a low leakage level (≤1×10⁻⁶) under low differential pressure conditions. -6 It can maintain ANSI Class VI sealing performance even under high pressure differential conditions (mL / s).

[0024] The valve features a split-type fixed cover design with mounting bolts and nuts, combined with a quick-release snap-fit ​​structure for the packing gland, reducing packing replacement time. The ball can be directly removed through the valve cover opening without disassembling the pipeline flange, making it particularly suitable for operating conditions containing particulate media or with frequent opening and closing, significantly reducing unplanned downtime losses.

[0025] The valve stem incorporates an anti-static spring, which conducts static electricity between the ball and the valve body (resistance ≤10Ω), preventing static buildup caused by media friction from leading to combustion or explosion. Testing has shown that this structure can withstand 10... 6 The opening and closing operation does not generate electrostatic sparks, meeting the ATEX explosion-proof certification requirements.

[0026] The valve achieves bidirectional zero leakage (GB / T 13927 Class A) through a combined sealing structure of valve seat and sealing ring. Under reverse pressure conditions in the pipeline, the floating direction of the ball is automatically adjusted to always maintain sealing contact with the high-pressure side valve seat, avoiding the risk of seal failure caused by backflow of the medium in traditional one-way sealing ball valves. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the main cross-sectional structure of a self-balancing floating ball valve proposed in this utility model;

[0028] Figure 2 This is a front sectional view of the fixed outer sheath and compression spring in a self-balancing floating ball valve proposed in this utility model.

[0029] In the diagram: 1. Valve body; 2. Sealing ring; 3. Valve seat; 4. Ball; 5. Valve stem; 6. Compression spring; 7. Gasket; 8. Mounting bolt; 9. Nut; 10. Valve cover; 11. Antistatic spring; 12. Packing body; 13. Packing gland; 14. First hex bolt; 15. Handle; 16. Second hex bolt; 17. Relief groove; 18. Adjusting bolt; 19. Fixing outer sleeve; 20. Annular groove; 21. Annular pressure plate. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0031] In one embodiment; reference Figure 1-2 A ball valve, comprising: a self-balancing floating ball valve, wherein the specific implementation is as follows: An opening is formed at the top of the valve body 1, which is connected to the valve cover 10 by four circumferentially distributed mounting bolts 8. The lower end of the mounting bolts 8 is fixed to the top of the valve body 1, and the upper end passes through the corresponding hole in the valve cover 10 and is locked by nuts 9. An annular metal gasket 7 is provided on the contact surface between the valve cover 10 and the valve body 1 to ensure sealing. The valve stem 5 vertically penetrates the center hole of the valve cover 10, and its bottom forms a sliding fit with the T-shaped slide rail at the top of the ball 4 through a rectangular slider, allowing the ball 4 to float at a displacement not exceeding 2 mm along the axial direction of the valve stem 5. The ball 4 is housed in a cylindrical chamber inside the valve body 1. Annular valve seats 3 are respectively provided at the upper and lower ends of the chamber. The outer edge of the valve seat 3 is embedded in the inner wall of the valve body 1 through an interference fit, and the inner edge forms a line contact seal with the surface of the ball 4. Two O-rings 2 are provided between each valve seat 3 and the valve body 1, located in the annular grooves 20 on the upper and lower end faces of the valve seat 3 and the inner wall of the valve body 1, respectively.

[0032] An outer sheath 19 is fixedly mounted on the middle of the outer wall of the valve stem 5. An annular groove 20 is formed on the lower end face of this sheath, and an axially sliding annular pressure plate 21 is embedded within the groove. A compression spring 6 is fitted onto the outside of the valve stem 5, with its upper and lower ends contacting the lower surface of the annular pressure plate 21 and the upper surface of the ball 4, respectively, via spring seats. A clearance groove 17 is formed at the top of the fixed outer sheath 19, and an adjusting bolt 18 vertically passes through a threaded hole at the bottom of this groove. Its lower end is rotatably connected to the annular pressure plate 21 via a thrust bearing. When the adjusting bolt 18 is rotated, the annular pressure plate 21 moves axially along the annular groove 20 of the fixed outer sheath 19, changing the preload of the compression spring 6. The adjustment range covers 0 to 500 Newtons.

[0033] This application can be used in the field of ball valves, or in other fields applicable to this application.

[0034] In another embodiment; reference Figure 1-2A self-balancing floating ball valve is described, applicable in the ball valve field. The valve cover 10 has a three-layer flexible graphite packing body 12 inside. A packing gland 13 is fixed above the packing via a slot. A first internal hexagon bolt 14 passes through the center hole of the gland, and the lower end of the bolt engages with the threaded hole at the top of the valve cover 10 to achieve axial positioning of the packing gland 13. A through hole is formed along the axis inside the valve stem 5, and an anti-static spring 11 is embedded in the hole. The upper and lower ends of the spring contact the inner wall of the valve stem 5 and the top boss of the ball 4, respectively, ensuring that the electrostatic conduction resistance between the ball 4 and the valve body 1 is less than 10 ohms.

[0035] During operation, turning the handle 15 counterclockwise rotates the valve stem 5, which in turn drives the ball 4 to rotate synchronously via a slider-rail structure. At the moment the valve opens, the medium pressure pushes the ball 4 slightly towards the inlet side, causing it to disengage from the valve seat 3 on the outlet side, creating a non-contact seal. At this point, the rotational torque is lower than in traditional structures, allowing the use of actuators with a diameter of DN50 or less. To adjust the spring pressure, first loosen the nut 9 and remove the mounting bolt 8. Lift the valve cover 10 along with the valve stem 5 from the valve body 1, remove the ball 4, and then replace the packing body 12. After reassembly, rotating the adjusting bolt 18 with a tool lowers the annular pressure plate 21 by 0.5 mm, increasing the spring preload by 100 Newtons to adapt to different operating conditions. This structure has been tested under 25 MPa pressure for 5000 opening and closing cycles, with the sealing surface wear less than 0.05 mm and the operating torque fluctuation not exceeding ±5%.

[0036] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A self-balancing floating ball valve, characterized in that, include: The valve body (1) has an opening at its top; The valve cover (10) is fixedly mounted on the top of the valve body (1) by means of a mounting assembly; Valve stem (5) rotates through valve cover (10); The ball (4) is located inside the valve body (1) and is slidably connected to the valve stem (5) through a slider and slide rail structure, allowing the ball (4) to float axially along the valve stem (5). The top of the valve stem (5) is fixedly mounted with a handle (15) by a second internal hex bolt (16). A sealing assembly, disposed inside the valve body (1), includes a valve seat (3) for forming a seal with the ball (4); The adjustment assembly includes a compression spring (6) and an adjustment mechanism, wherein the compression spring (6) acts on the ball (4) and the adjustment mechanism is used to adjust the preload of the compression spring (6); When the valve is opened, the fluid pressure causes the ball (4) to float upstream, reducing the contact pressure between the ball (4) and the valve seat (3), thereby reducing the starting torque.

2. The self-balancing floating ball valve according to claim 1, characterized in that, The mounting assembly includes a plurality of mounting bolts (8), which are fixed to the top of the valve body (1) and threaded with nuts (9) to fix the valve cover (10). A gasket (7) is provided between the valve cover (10) and the valve body (1).

3. The self-balancing floating ball valve according to claim 1, characterized in that, The sealing assembly also includes a sealing ring (2) disposed between the valve seat (3) and the valve body (1) to enhance the seal.

4. The self-balancing floating ball valve according to claim 1, characterized in that, The adjustment assembly includes a fixed outer sleeve (19) fixedly fitted onto the valve stem (5), an annular pressure plate (21) slidably disposed in the annular groove (20) of the fixed outer sleeve (19), and a compression spring (6) fitted onto the outside of the valve stem (5), with one end abutting against the annular pressure plate (21) and the other end abutting against the ball (4).

5. The self-balancing floating ball valve according to claim 4, characterized in that, The adjustment mechanism includes an adjustment bolt (18) threaded through the relief groove (17) of the fixed outer sheath (19) and rotatably connected to the annular pressure plate (21); rotating the adjustment bolt (18) drives the annular pressure plate (21) to move, so as to adjust the compression amount of the compression spring (6).

6. The self-balancing floating ball valve according to claim 1, characterized in that, It also includes a packing body (12) disposed inside the valve cover (10), and a packing gland (13) fixed to the valve cover (10) by a first internal hex bolt (14) for sealing the valve stem (5).

7. The self-balancing floating ball valve according to claim 1, characterized in that, It also includes an antistatic spring (11) embedded inside the valve stem (5), connecting the ball (4) and the valve stem (5), for dissipating static electricity.

8. The self-balancing floating ball valve according to claim 5, characterized in that, The adjusting bolt (18) is rotatably connected to the annular pressure plate (21) through the thrust bearing, so as to realize stepless adjustment of the spring preload.

Images