High-temperature resistant, zero-friction, soft-seal ball valve

Abstract

This invention discloses a high-temperature resistant, zero-friction, soft-seal ball valve. The ball valve includes a valve body, a ball, a valve stem, a valve cover, and an actuator. The left valve stem has an inlet channel A, and the right valve stem has an outlet channel A, forming a first cooling circuit flowing through the ball. The valve cover has an inlet channel B and an outlet channel B, forming a second cooling circuit flowing through the valve cover. The valve body has an inlet channel C and an outlet channel C, forming a third cooling circuit flowing through the valve body. An inflatable and deflated sealing ring is provided between the valve cover, valve seat, and the ball's sealing surface. The valve cover has a vent channel connected to the sealing ring's inflation port and a pneumatic control system. The pneumatic control system includes a filter pressure reducing valve, a solenoid valve, a pneumatic control valve, a quick-release valve, and a pressure transmitter, and controls the inflation and deflation of the sealing ring through a control center. This invention cools the sealing ring through a dual cooling circuit, successfully applying soft sealing to high-temperature conditions.

Description

Technical Field

[0001] This invention belongs to the field of valve technology, and in particular relates to a soft-seal ball valve with zero friction for opening and closing, suitable for high-temperature operating conditions. Background Technology

[0002] Ball valves are one of the most widely used valve types in industrial pipeline systems. They control the flow of media by rotating a ball. Based on the sealing method, ball valves can be divided into two main categories: hard-seal ball valves and soft-seal ball valves.

[0003] Hard-seal ball valves typically use a metal-to-metal sealing pair, which has the advantage of excellent high-temperature resistance, enabling them to operate normally at 600℃ or even higher. However, hard-seal ball valves have the following inherent drawbacks: First, the sealing surface requires extremely high machining precision, resulting in high manufacturing costs; second, the metal sealing surface is constantly in contact and friction during opening and closing, leading to high opening and closing torque, easy wear of the sealing surface, and a limited service life; third, after long-term use, the sealing surface is prone to scratches and deformation, resulting in decreased sealing performance and leakage.

[0004] Soft-seal ball valves typically use non-metallic materials such as polytetrafluoroethylene (PTFE) and rubber as sealing elements. Their advantages include excellent sealing performance, achieving zero leakage, low opening and closing torque, and minimal wear on the sealing surface. However, soft-seal materials have limited temperature resistance; ordinary sealing rings age, carbonize, and fail above 200℃, and even high-performance fluororubber has a long-term operating temperature that rarely exceeds 350℃. Therefore, in high-temperature conditions down to 600℃, soft-seal solutions are almost unusable in current technology, forcing the selection of hard-seal ball valves at the expense of sealing performance and service life.

[0005] Furthermore, regardless of whether a ball valve has a hard seal or a soft seal, there is always contact friction on the sealing surface during the opening and closing process. This not only leads to wear on the sealing surface, but also generates greater opening and closing resistance, requiring the configuration of a high-power actuator, which increases equipment cost and energy consumption.

[0006] Therefore, how to combine the excellent sealing performance of soft seals with their adaptability to high-temperature conditions, while eliminating friction on the sealing surface during the opening and closing process, is a technical problem that has long remained unsolved in this field. Summary of the Invention

[0007] The purpose of this invention is to provide a high-temperature resistant, zero-friction, soft-seal ball valve to solve the problems of existing soft-seal ball valves being unable to adapt to high-temperature operating conditions and the decrease in sealing performance caused by wear of the sealing surface during opening and closing.

[0008] To achieve the above objectives, the present invention provides the following technical solution: A high-temperature resistant, zero-friction, soft-seal ball valve includes a valve body, a ball, a valve stem, a valve seat, a valve cover, and an actuator. The ball is disposed within the valve body cavity, and packing is provided between the valve body and the valve stem. The valve stem includes a left valve stem and a right valve stem, which are respectively disposed at the left and right ends of the ball. A bracket is provided at the right end of the right valve stem, and the actuator is mounted on the bracket. The right valve stem passes through the bracket and connects to the actuator. The valve cover is disposed on the upper part of the valve body. The valve cover is characterized by having an inlet channel A inside the left valve stem and an outlet channel A inside the right valve stem. The inlet channel A connects to an external inlet valve A, and the inlet channel A and outlet channel A are connected, allowing cooling water to flow through the entire ball. The valve cover has an inlet channel B and an outlet channel B, with the inlet channel B connecting to an external inlet valve A. An external inlet valve B connects the inlet channel B to the outlet channel B, allowing cooling water to flow through the inside of the valve cover. The valve body has an outer wall, and the gap between the outer wall and the valve body forms a cooling water channel. The outer wall has an inlet channel C and an outlet channel C, which connect to allow cooling water to flow through the valve body. An inflatable and deflated sealing ring is provided between the valve cover, valve seat, and the ball sealing surface. A vent is also provided inside the valve cover, with one end connected to the inflation hole of the sealing ring and the other end connected to an external pneumatic control system. The sealing ring expands and presses against the ball surface to achieve a seal when inflated, and contracts and separates from the ball when deflated to achieve zero-friction opening and closing. The pneumatic control system is used to control the inflation and deflation of the sealing ring.

[0009] Furthermore, the pneumatic control system includes a filter pressure reducing valve, a solenoid valve, a pneumatic control valve, a quick exhaust valve, and an external air source; the inlet end of the filter pressure reducing valve is connected to the external air source, and the outlet end is connected to the inlet end of the solenoid valve and the inlet end of the pneumatic control valve, respectively; the outlet end of the solenoid valve is connected to the control end of the pneumatic control valve; the outlet end of the pneumatic control valve is connected to the air inlet of the sealing ring via the quick exhaust valve.

[0010] Furthermore, the pneumatic control system also includes a pressure transmitter, which is installed in the air path between the air outlet of the pneumatic control valve and the sealing ring, for real-time detection of the pressure inside the sealing ring and feedback of the pressure signal to the central control center; the central control center is electrically connected to the solenoid valve and the pressure transmitter.

[0011] Furthermore, the solenoid valve is a two-position three-way solenoid valve, which, in the de-energized state, guides the air path from the filter pressure reducing valve to the control end of the pneumatic control valve, and cuts off the air path in the energized state.

[0012] Furthermore, the pneumatic control valve is a two-position three-way pneumatic control valve.

[0013] Furthermore, the pressure transmitter is equipped with a remote controller.

[0014] Furthermore, the sealing ring is made of a high-temperature resistant soft sealing material.

[0015] Furthermore, the right valve stem is equipped with a limit switch to detect the opening and closing status of the valve.

[0016] Furthermore, the fail-safe mode of the ball valve is normally closed. In the event of a power outage or gas outage, the solenoid valve loses power, the pneumatic control valve remains normally open, and the sealing ring is in a gas-filled sealing state.

[0017] Compared with the prior art, the present invention has the following beneficial effects: Achieving soft-seal applications in high-temperature conditions: By incorporating a water-cooling channel within the valve body, the area around the sealing ring is continuously cooled, reducing the temperature to below 350℃. This allows the seal to maintain elasticity and sealing performance even under high-temperature conditions with media temperatures up to 600℃, successfully applying the zero-leakage advantage of soft seals to high-temperature applications. The valve's opening and closing processes occur entirely during the deflation and contraction of the sealing ring, completely separating the ball from the sealing ring and eliminating any contact friction. This eliminates wear between the sealing surfaces, resulting in minimal opening and closing torque. This not only extends the service life of the seal and the ball but also reduces the actuator's... Power configuration reduces equipment costs and operating energy consumption; intelligent automatic control is achieved through a control system composed of a central control center, solenoid valves, pneumatic control valves, quick exhaust valves, and pressure transmitters. The inflation and deflation of the sealing rings are fully automated, with precise pressure control, fast response speed, and real-time monitoring of valve status via a remote central control system; adopting an FC normally closed fail-safe mode, in abnormal situations such as power failure or gas interruption, the solenoid valve automatically de-energizes, the pneumatic control valve remains normally open, and the sealing rings automatically inflate and seal, ensuring that the valve is in a safe closed position under fault conditions, avoiding media leakage, and ensuring safe system operation. Attached Figure Description

[0018] Figure 1 This is a cross-sectional schematic diagram of the overall structure of the ball valve of the present invention.

[0019] Figure 2 This is a schematic diagram of the component connections of the pneumatic control system of the present invention.

[0020] Figure 3 This is a schematic diagram of the pneumatic control system of the present invention.

[0021] In the diagram: 1. Valve body; 2. Left valve stem; 3. Ball; 4. Right valve stem; 5. Sealing ring; 6. Valve cover; 7. Packing; 8. Limit switch; 9. Bracket; 10. Actuator; 11. Pneumatic control system; 111. Filter pressure reducing valve; 112. Pneumatic control valve; 113. Solenoid valve; 114. Quick exhaust valve; 115. Pressure transmitter; 116. External air source; 12. Vent duct; 13. Water inlet channel A; 14. Water outlet channel A; 15. Water inlet valve A; 16. Water inlet channel B; 17. Water outlet channel B; 18. Water inlet valve B; 19. Water inlet channel C; 20. Water outlet channel C; 21. Outer wall; 22. Control center. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be further described with reference to the accompanying drawings.

[0023] As attached Figure 1-3 As shown, this embodiment provides a high-temperature resistant, zero-friction, soft-seal ball valve, including a valve body 1, a ball 3, a valve stem, a valve cover 6, and an actuator 10. The ball 3 is disposed within the inner cavity of the valve body 1, and a left valve stem 2 and a right valve stem 4 are respectively located at the left and right ends of the ball 3. Packing 7 is provided between the valve body 1 and both the left and right valve stems 2 and 4 to achieve a seal at the valve stem. A bracket 9 is provided at the right end of the right valve stem 4, and the actuator 10 is mounted on the bracket 9, with the right valve stem 4 passing through the bracket 9 and connecting to the actuator 10. The valve cover 6 is located on the upper part of the valve body 1.

[0024] The core technical features of this invention lie in the design of the cooling system and the sealing system.

[0025] The cooling system consists of three independent cooling water circuits: the first cooling circuit is located inside the valve stem, with an inlet channel A13 inside the left valve stem 2 and an outlet channel A14 inside the right valve stem 4. The inlet channel A13 connects to the external inlet valve A15, and the inlet channel A13 and outlet channel A14 are connected through the internal flow channel of the sphere 3. During operation, cooling water enters from the inlet valve A15, flows through the inlet channel A13, the interior of the sphere 3, and the outlet channel A14 before being discharged, allowing the cooling water to flow through the entire sphere 3 and cool the sphere 3 as a whole. The second cooling circuit is located inside the valve cover 6. The valve cover 6 has an inlet channel B16 and an outlet channel B17. The inlet channel B16 is connected to the external inlet valve B18. The inlet channel B16 and the outlet channel B17 are interconnected inside the valve cover 6 to form a cooling water circulation path, allowing cooling water to flow through the inside of the valve cover 6 and cool the sealing ring 5 between the valve cover 6 and the sealing surface of the ball 3. The third cooling circuit is formed by the gap between the valve body 1 and the outer wall 21. The outer wall 21 has an inlet channel C19 and an outlet channel C20. The inlet channel C19 and the outlet channel C20 are connected, and cooling water flows through the valve body 1 to cool the valve body 1.

[0026] Through the synergistic effect of the three cooling circuits mentioned above, when the sealing ring 5 is made of high-temperature resistant rubber, its actual working temperature can always be maintained below 350°C under high-temperature conditions with a medium temperature of 600°C. This ensures that the sealing ring 5 is in a good elastic working state for a long time, and allows the zero-leakage advantage of soft seals to be applied in high-temperature fields.

[0027] A sealing system is installed between the sealing surfaces of the valve cover 6, valve seat, and ball 3. An inflatable and deflated sealing ring 5 is provided between the sealing surfaces of the valve cover 6, valve seat, and ball 3. The sealing ring 5 is made of high-temperature resistant rubber and has a hollow annular cross-section, allowing air to be contained within the hollow cavity. A vent 12 is also provided inside the valve cover 6. One end of the vent 12 connects to the inflation hole of the sealing ring 5, and the other end connects to the external pneumatic control system 11.

[0028] The pneumatic control system 11 includes a filter pressure reducing valve 111, a solenoid valve 113, a pneumatic control valve 112, a quick-exhaust valve 114, and an external air source 116. The inlet of the filter pressure reducing valve 111 is connected to the external air source 116, which operates at a pressure of 1.4 to 1.6 MPa. The filter pressure reducing valve 111 filters and regulates the pressure of the air source, ensuring that the compressed air entering the system is clean and has stable pressure. The outlet of the filter pressure reducing valve 111 is divided into two paths: one connected to the inlet of the solenoid valve 113, and the other connected to the inlet of the pneumatic control valve 112. The solenoid valve 113 is a two-position three-way solenoid valve, whose outlet is connected to the control end of the pneumatic control valve 112 to control its opening and closing status. The pneumatic control valve 112 is a two-position three-way pneumatic control valve, whose outlet is connected to the inflation port of the sealing ring 5 via the quick-exhaust valve 114. The pneumatic control system 11 also includes a pressure transmitter 115, which is installed in the air path between the outlet of the pneumatic control valve 112 and the sealing ring 5. The pressure transmitter 115 is used to detect the gas pressure within the sealing ring 5 in real time and convert the pressure signal into an electrical signal to be fed back to the control center 22. The pressure transmitter 115 is equipped with a remote controller, enabling remote monitoring of the valve's sealing status. The control center 22 is electrically connected to the solenoid valve 113 and the pressure transmitter 115, forming a closed-loop control system. A limit switch 8 is installed on the right valve stem 4 to detect the valve's opening and closing status and feed the signal back to the control center 22.

[0029] The working principle of this valve is as follows: Closing and Sealing Process: When the pipeline system needs to close the valve, the control center 22 issues a closing command. At this time, the ball 3 has already been pre-rotated to the closed position before opening. The control center 22 does not supply power to the solenoid valve 113, and the solenoid valve 113 is in a de-energized state. In the de-energized state, the internal valve core of the solenoid valve 113 is guided by the spring force through the air passage from the filter pressure reducing valve 111 to the control end of the pneumatic control valve 112. The air source pressure acts on the control end of the pneumatic control valve 112 through the solenoid valve 113, keeping the pneumatic control valve 112 in the open position. The air source inflates the sealing ring 5 through the pneumatic control valve 112 and the quick exhaust valve 114. The sealing ring 5 gradually expands and finally tightly adheres to and presses against the surface of the ball 3, forming a reliable seal. The pressure transmitter 115 monitors the inflation pressure in real time. When the pressure reaches the preset working pressure, it sends a signal to the control center 22 indicating that the sealing action is complete.

[0030] Initiation of pressure relief process: When the pipeline system needs to open a valve, the control center 22 issues an opening command. First, the control center 22 energizes the solenoid valve 113. In the energized state, the internal valve core of the solenoid valve 113 switches positions, cutting off the air path from the filter pressure reducing valve 111 to the control end of the pneumatic control valve 112, and venting any residual air from the control end of the pneumatic control valve 112. The pneumatic control valve 112 immediately closes after losing control pressure, cutting off the main air path supplying air to the sealing ring 5. After the pneumatic control valve 112 closes, the pressure in the pipeline between the sealing ring 5 and the pneumatic control valve 112 drops, triggering the quick-release valve 114 to open the exhaust port. The compressed air in the sealing ring 5 is discharged into the atmosphere through the quick-release valve 114 in a very short time. The sealing ring 5 quickly contracts, completely separating from the ball 3, without generating any frictional resistance to the subsequent rotation of the ball 3. The pressure transmitter 115 detects the pressure drop to atmospheric pressure and sends a pressure relief completion signal back to the control center 22. Subsequently, the control center 22 controls the actuator 10 to drive the right valve stem 4 to rotate, which in turn drives the ball 3 to the open position, allowing the medium to flow. During the entire rotation of the ball 3, since the sealing ring 5 has fully contracted, there is no contact between the ball 3 and the sealing ring 5, achieving zero-friction opening and closing.

[0031] Fail-safe protection: This valve adopts an FC normally closed fail-safe design. When the system experiences abnormal conditions such as power failure or gas supply interruption, the solenoid valve 113 automatically de-energizes and switches to the normally open state. The gas supply pressure acts on the control terminal of the pneumatic control valve 112 to keep it open, and the gas supply continuously inflates the sealing ring 5. The sealing ring 5 expands and presses against the ball 3, and the valve automatically returns to the closed and sealed state. This design ensures that the valve is always in a safe position under fault conditions, preventing media leakage and protecting the safety of downstream equipment and personnel.

[0032] Cooling Circulation: After the valve is put into operation, the three cooling circuits operate continuously. When inlet valve A15 opens, cooling water flows into the ball 3 through inlet channel A13, absorbs heat, and is discharged through outlet channel A14, thus cooling the ball 3 as a whole. Simultaneously, inlet valve B18 opens, and cooling water flows into the valve cover 6 through inlet channel B16, passes around the sealing ring 5, and is discharged through outlet channel B17, forcibly cooling the sealing ring 5. Also simultaneously, cooling water flows into the gap between the valve body 1 and the outer wall 21 through inlet channel C19 and is discharged through outlet channel C20, cooling the valve body 1. The flow rate and pressure of the cooling water can be adjusted according to the medium temperature and the allowable operating temperature of the sealing ring 5. Under high-temperature conditions with a medium temperature of 600℃, by rationally designing the heat exchange area of ​​the cooling channels and the cooling water flow rate, the actual temperature of the sealing ring 5 can be controlled below 350℃, ensuring that it remains in a good elastic working state for a long time, and that its sealing performance is stable and reliable.

[0033] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A high-temperature-resistant opening and closing zero-friction soft sealing ball valve, comprising a valve body (1), a ball body (3), a valve stem, a valve seat, a valve cover (6) and an actuator (10), the ball body (3) is arranged in the inner cavity of the valve body (1), the valve stem comprises a left valve stem (2) and a right valve stem (4), the left valve stem (2) and the right valve stem (4) are arranged at the left and right ends of the ball body (3) respectively, a packing (7) is arranged between the valve body (1) and the valve stem, a bracket (9) is arranged at the right end of the right valve stem (4), the actuator (10) is arranged on the bracket (9), the right valve stem (4) is connected with the actuator (10) through the bracket (9), and the valve cover (6) is arranged on the upper portion of the valve body (1), characterized in that: The left valve stem (2) is provided with an inlet channel A (13), and the right valve stem (4) is provided with an outlet channel A (14). The inlet channel A (13) is connected to the external inlet valve A (15). The inlet channel A (13) and the outlet channel A (14) are connected, so that the cooling water can flow through the entire sphere (3). The valve cover (6) is provided with an inlet channel B (16) and an outlet channel B (17). The inlet channel B (16) is connected to the external inlet valve B (18). The inlet channel B (16) and the outlet channel B (17) are connected, so that the cooling water can flow through the inside of the valve cover (6). The valve body (1) is provided with an outer wall (21). The gap between the outer wall (21) and the valve body (1) forms a cooling water channel. The valve body (1) is provided with an inlet channel C (19) and an outlet channel C (20). The inlet channel C (19) and the outlet channel C (20) are connected to allow cooling water to flow through the valve body (1). A gas-fillable sealing ring (5) is provided between the valve cover (6), the valve seat and the sealing surface of the ball (3). A venting channel (12) is also provided inside the valve cover (6). One end of the venting channel (12) is connected to the air inlet of the sealing ring (5), and the other end is connected to the external pneumatic control system (11). The sealing ring (5) expands and presses the surface of the ball (3) to achieve sealing when it is inflated. When it is deflated, it contracts and separates from the ball (3) to achieve zero-friction opening and closing. The pneumatic control system (11) is used to control the inflation and deflation of the sealing ring (5). ​ 2. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 1, characterized in that: The pneumatic control system (11) includes a filter pressure reducing valve (111), a solenoid valve (113), a pneumatic control valve (112), a quick exhaust valve (114), and an external air source (116). The air inlet of the filter pressure reducing valve (111) is connected to the external air source (116), and the air outlet is connected to the air inlet of the solenoid valve (113) and the air inlet of the pneumatic control valve (112), respectively. The air outlet of the solenoid valve (113) is connected to the control end of the pneumatic control valve (112). The air outlet of the pneumatic control valve (112) is connected to the air inlet of the sealing ring (5) via the quick exhaust valve (114).

3. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 2, characterized in that: The pneumatic control system (11) also includes a pressure transmitter (115), which is located on the air path between the outlet of the pneumatic control valve (112) and the sealing ring (5) for real-time detection of the pressure inside the sealing ring (5) and feeding the pressure signal back to the control center (22); the control center (22) is electrically connected to the solenoid valve (113) and the pressure transmitter (115).

4. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 3, characterized in that: The solenoid valve (113) is a two-position three-way solenoid valve. In the de-energized state, it guides the air path from the filter pressure reducing valve (111) to the control end of the pneumatic control valve (112), and cuts off the air path in the energized state.

5. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 2, characterized in that: The pneumatic control valve (112) is a two-position three-way pneumatic control valve.

6. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 3, characterized in that: The pressure transmitter (115) is equipped with a remote controller.

7. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 1, characterized in that: The sealing ring (5) is made of high-temperature resistant soft sealing material.

8. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 1, characterized in that: A limit switch (8) is provided on the right valve stem (4) to detect the opening and closing status of the valve.

9. The high-temperature resistant, zero-friction, soft-seal ball valve for opening and closing according to claim 3, characterized in that: The fail-safe mode of the ball valve is normally closed. In the event of power failure or gas failure, the solenoid valve (113) loses power, the pneumatic control valve (112) remains normally open, and the sealing ring (5) is in a gas-filled sealing state.

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