Impact-proof spring safety valve

Abstract

The present application relates to a kind of anti-impact spring safety valve, including valve body, valve seat, valve flap, backflushing disc, guide sleeve, valve cover, pressure setting device, the buffer device is composed of the buffer ring of the lower end of guide sleeve and the piston type damping mechanism in backflushing disc;In the process of valve flap backseat, reduce closing speed, reduce the impact force of valve flap sealing surface impact valve seat sealing surface, effectively prevent the damage of valve flap sealing surface, improve sealing performance and product service life.

Description

Technical Field

[0001] This invention belongs to the field of valves, and particularly relates to a spring-loaded soft-seal safety valve. Background Technology

[0002] Traditional safety valves used in applications requiring high sealing often employ a soft-seal structure. The valve seat sealing surface is made of metal, while the valve disc sealing surface is made of non-metallic material to achieve the high sealing requirements. However, this design has the disadvantage that when the valve disc opens and closes, the valve disc sealing surface rapidly impacts the valve seat sealing surface with significant force. Frequent opening and closing can easily damage the valve disc sealing surface, causing the valve to lose its sealing function and resulting in a short product lifespan. Summary of the Invention

[0003] This invention addresses the shortcomings of existing technologies by providing an anti-impact spring-loaded safety valve that reduces the valve disc closing speed and impact force during closure, ensuring reliable sealing performance and a long service life.

[0004] The technical solution of this invention is as follows: An anti-impact spring-type safety valve includes a valve body, valve seat, valve disc, backflush disc, guide sleeve, valve cover, and pressure setting device. The valve disc is fixedly installed on the lower end face of the backflush disc using a soft sealing gasket, forming a soft sealing pair structure with the metal sealing surface of the valve seat. The guide post on the upper part of the backflush disc is movably engaged with the guide hole of the guide sleeve. The radial disc at the upper end of the guide sleeve is press-fitted between the valve body and the valve cover. The pressure setting device includes a valve stem, a spring, and an adjusting screw sleeve. The lower end of the valve stem presses against the center of the back side of the backflush disc. The spring is installed between the upper and lower spring seats on the valve stem. The adjusting screw sleeve is threaded onto the valve cover, with its lower end pressing against the upper end face of the upper spring seat. The valve is characterized by a buffer device provided between the guide sleeve and the backflush disc. The buffer device is located between the lower end of the guide sleeve and the backflush disc. The device consists of a buffer ring at the end and a piston-type damping mechanism inside the recoil plate. A buffer spring is connected between the upper end of the buffer ring and the guide sleeve. The inner hole of the buffer ring is in movable fit with the outer circular surface of the guide post on the back of the recoil plate. The piston-type damping mechanism consists of a damping cavity and a damping piston. The damping cavity is connected to the outlet cavity at the lower end face of the recoil plate through a one-way valve in the inlet of the drainage hole. A damping hole is set between the drainage hole and the outlet cavity. The damping piston is movably installed in the piston cavity connected to the damping cavity. Several pistons are evenly arranged radially around the damping cavity. The center of the damping piston is provided with a push rod that contacts the inner circular wall of the buffer ring. The upper end of the inner circular wall of the buffer ring is provided with a conical buffer surface. A return spring is set between the damping piston on the outer periphery of the push rod and the step inside the piston cavity.

[0005] Ideally, the damping cavity and damping piston are located inside the core column, which is installed in the cylindrical hole of the guide post on the back of the recoil plate by a fixing ring, and the return spring is installed between the damping piston and the inner wall of the cylindrical hole on the recoil plate.

[0006] Ideally, a steel ball is placed between the push rod and the inner wall of the buffer ring, and the steel ball is placed in a radial hole between the inner wall of the cylindrical hole of the recoil plate and the outer cylindrical surface.

[0007] Preferably, the upper end of the buffer ring has a guide cylinder that extends upward and guides the outer circular surface of the guide sleeve; there is a radial limiting step between the conical buffer surface and the inner wall of the guide cylinder that cooperates with the lower end face of the guide sleeve; and there is a buffer groove between the lower inner hole of the guide sleeve and the outer circular surface of the guide post of the backflush disc.

[0008] The beneficial effects of this invention compared with the prior art are: by setting a buffer device between the guide sleeve and the backflush disc, the closing speed is reduced during the valve disc reseating process, the impact force of the valve disc sealing surface on the valve seat sealing surface is reduced, the damage to the valve disc sealing surface is effectively prevented, and the sealing performance and product service life are improved. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of the present invention.

[0010] Figure 2 This is the present invention. Figure 1 A schematic diagram of the buffer device between the middle recoil plate and the guide sleeve.

[0011] Figure 3 This is the present invention. Figure 2 A schematic diagram of the structure of the middle counter-pressure plate.

[0012] Figure 4 This is the present invention. Figure 2 A schematic diagram of the structure of the guide sleeve and the buffer ring.

[0013] In the diagram: 1 Valve body, 2 Valve seat, 3 Adjusting ring, 4 Backflush disc, 5 Buffer ring, 6 Buffer spring, 7 Guide sleeve, 8 Valve cover, 9 Valve stem, 10 Spring, 11 Upper spring seat, 12 Adjusting screw sleeve, 13 Valve cap, 14 Pad, 15 Outlet cavity, 16 Inlet cavity, 17 Core column, 18 Fixing ring, 19 Positioning groove, 20 Positioning block, 21 Buffer groove, 22 Damping piston, 23 Return spring, 24 Steel ball, 25 Plug, 26 Damping hole, 27 Return spring, 28 One-way valve disc, 29 Inlet, 30 Valve disc, 31 Drain hole, 32 Valve disc sealing surface, 33 Damping cavity, 34 Conical buffer surface. Implementation

[0014] like Figure 1The anti-impact spring-loaded safety valve shown includes a valve body 1, a valve seat 2, a valve disc 30, a backflush disc 4, a guide sleeve 7, a valve cover 8, and a pressure setting device. The valve disc 30 is fixedly installed on the lower end face of the backflush disc 4 using a fluoroplastic sealing gasket. A valve disc sealing surface 32 is provided inside the lower end face of the backflush disc 4, forming a soft sealing pair structure with the metal sealing surface of the valve seat 2. The valve seat 2 is installed inside the inlet cavity 16 of the valve body 1. An adjusting ring 3 is provided on the outer side of the metal sealing surface of the valve seat 2 to adjust the opening height of the valve disc 30. The guide post on the upper part of the backflush disc 4 is movably engaged with the guide hole of the guide sleeve 7. The radial disc seal at the upper end of the guide sleeve 7 is press-fitted onto the valve body 1. Between the valve cover 8 and the pressure setting device, a valve stem 9, a spring 10, and an adjusting screw sleeve 12 are provided. The lower end of the valve stem 9 presses against the center of the back side of the recoil disc 4. The spring 10 is installed between the upper and lower spring seats on the valve stem 9. The adjusting screw sleeve 12 is threaded onto the valve cover 8, with its lower end pressing against the upper end face of the upper spring seat 11. By adjusting the axial position of the adjusting screw sleeve 12, the compression force of the spring 10 is adjusted, and the setting pressure value is set. A valve cap 13 is provided at the upper end of the valve cover 8 to prevent dust from entering the inner cavity of the valve cover 8. The device is characterized by a buffer device provided between the guide sleeve 7 and the recoil disc 4, wherein the buffer device is located between the guide sleeve 7 and the lower end of the guide sleeve 7. The buffer ring 5 and the piston-type damping mechanism inside the recoil disc 4 are composed of a buffer ring 5 and a guide sleeve 7. A buffer spring 6 is connected between the upper end of the buffer ring 5 and the guide sleeve 7. The inner hole of the buffer ring 5 is in movable fit with the outer circular surface of the guide post on the back of the recoil disc 4. The piston-type damping mechanism is composed of a damping cavity 33 and a damping piston 22. The damping cavity 33 is connected to the outlet cavity 15 at the lower end face of the recoil disc 4 through a one-way valve in the drain hole 31. The one-way valve is composed of a one-way valve disc 28 and a return spring 27. The lower end face of the one-way valve disc 28 and the step in the inlet 29 at the lower end face of the recoil disc 4 cooperate with each other to form a sealing pair. The return spring 27 is installed on the one-way valve disc 28. Between the end face and the lower end face of the blockage, a damping hole 26 is provided between the drainage hole 31 and the outlet cavity 15. During the closing process of the valve disc 30, the medium in the damping cavity 33 is slowly discharged into the outlet cavity 15 through the drainage hole 31 and the damping hole 26. The damping piston 22 is movably installed in the piston cavity communicating with the damping cavity 33. Several piston cavities are evenly arranged radially around the damping cavity 33. The center of the radially outer end face of the damping piston 22 is provided with a push rod that contacts the inner circular wall of the buffer ring 5. Here, radial refers to the diameter direction of the guide post of the recoil disc 4. The upper end of the inner circular wall of the buffer ring 5 is provided with a conical buffer surface 34, such as... Figure 4 As shown. When the valve opens, the backflush plate 4 rises, and the medium pressure at the inlet 29 pushes the one-way valve disc 28 to open. The medium pressure enters the damping chamber 33, pushing the damping piston 22, causing the end of the push rod to enter the conical buffer surface 34, as shown. Figure 3 As shown. A return spring 23 is installed between the damping piston 22 on the outer periphery of the push rod and the step inside the piston chamber. After the pressure in the damping chamber 33 is released, the damping piston 22 is reset. The pressure in the damping chamber 33 is slowly released through the damping hole 26, which reduces the closing speed of the valve disc 30 and prevents the valve disc 30 from impacting the sealing surface of the valve seat 2.

[0015] The damping cavity 33 and the damping piston 22 are disposed within a core column 17. The core column 17 is mounted in the cylindrical hole of the guide post on the back of the recoil disc 4 by a fixing ring 18. The return spring 23 is installed between the damping piston 22 and the inner wall of the cylindrical hole on the recoil disc 4, facilitating the machining of the damping cavity 33 and the assembly of the damping piston 22 and the return spring 23. A pad 14 is provided in the center hole of the upper end face of the core column 17 to ensure flexible contact between the valve stem 9 and the recoil disc 4. A positioning block 20 is provided on the outer circular surface of the core column 17 to cooperate with the positioning groove 19 in the cylindrical hole of the recoil disc 4, preventing the core column 17 from rotating within the cylindrical hole. Figure 3 As shown.

[0016] A steel ball 24 is provided between the push rod and the inner wall of the buffer ring 5. The steel ball 24 is placed in the radial hole between the inner wall of the cylindrical hole of the recoil plate 4 and the outer cylindrical surface.

[0017] The upper end of the buffer ring 5 has an upwardly extending guide cylinder that guides and engages with the outer circular surface of the guide sleeve 7, improving the stability of the axial movement of the buffer ring 5; between the conical buffer surface 34 and the inner wall of the guide cylinder, there is a radial limiting step that engages with the lower end face of the guide sleeve 7, restricting the axial position of the buffer ring 5 on the outer cylindrical surface of the guide post of the backflushing disc 4, so that after the valve disc 30 is opened, the steel ball 24 is embedded in the conical buffer surface 34, such as... Figure 2 As shown, there is a buffer groove 21 between the lower inner hole of the guide sleeve 7 and the outer circular surface of the guide post of the backflush disc 4, so that the steel ball 24 can smoothly bounce into the conical buffer surface 34.

[0018] Work process: Opening process: When the medium pressure in the inlet chamber 16 reaches the set pressure value, the upward force of the medium acting on the valve disc 30 is greater than the downward force of the spring 10 acting on the valve disc 30 through the valve stem 9. The valve disc 30 and the backwash plate 4 move upward, and the valve opens. At this time, the medium in the outlet chamber 15 pushes the one-way valve disc 28 to open, the inlet 29 connects to the drainage hole 31, and the medium enters the damping chamber 33. The medium in the damping chamber 33 pushes the damping piston 22 to move outward, and the steel ball 24 enters the buffer groove 21 above the conical buffer surface 34.

[0019] Closing process: When the medium pressure in the inlet chamber 16 reaches the reseating pressure value, the upward force of the medium acting on the valve disc 30 is less than the downward force of the spring 10 acting on the valve disc 30 through the valve stem 9. The valve disc 30 and the backflush plate 4 move downward. At this time, the one-way valve disc 28 moves downward and closes under the action of the return spring 27. The drain hole 31 is cut off from the inlet 29. The medium in the damping chamber 33 can only be slowly discharged through the damping hole 26. Since the downward speed of the valve disc 30 is very fast, the damping piston 22 cannot move quickly to the center of the damping chamber 33 under the action of the return spring 23. Therefore, when the steel ball 24 moves downward quickly with the backflush plate 4, it presses the conical buffer surface 34, drives the buffer ring 5 to move downward, and stretches the buffer spring 6, which slows down the downward speed of the valve disc 30 and the backflush plate 4, reduces the impact force of the valve disc 30 sealing surface on the valve seat 2 sealing surface, and prevents the valve disc 30 sealing surface from being damaged by impact. Simultaneously, as the medium in the damping chamber 33 is completely discharged through the damping hole 26, the damping piston 22 returns to its initial state under the action of the return spring 23, the buffer ring 5 moves upward under the tension of the buffer spring 6, the steel ball 24 disengages from the conical buffer surface 34, the buffer ring 5 returns to its initial state, the sealing surface of the valve disc 30 presses against the sealing surface of the valve seat 2 again, and the valve closes.

Claims

1. An anti-impact spring-loaded safety valve, comprising a valve body (1), a valve seat (2), a valve disc (30), a backflush disc (4), a guide sleeve (7), a valve cover (8), and a pressure setting device; characterized in that: A buffer device is provided between the guide sleeve (7) and the recoil plate (4). The buffer device consists of a buffer ring (5) located at the lower end of the guide sleeve (7) and a piston-type damping mechanism provided inside the recoil plate (4). A buffer spring (6) is connected between the upper end of the buffer ring (5) and the guide sleeve (7). The inner hole of the buffer ring (5) is in movable fit with the outer circular surface of the guide post on the back of the recoil plate (4). The piston-type damping mechanism consists of a damping cavity (33) and a damping piston (22). The damping cavity (33) is connected to the recoil plate (4) through a one-way valve in the drainage hole (31) and an inlet (22) on the lower end face of the recoil plate (4). 9) Connected to the outlet cavity (15), a damping hole (26) is provided between the drainage hole (31) and the outlet cavity (15); the damping piston (22) is movably installed in the piston cavity connected to the damping cavity (33). The piston cavity is arranged radially and evenly around the damping cavity (33). The center of the radial outer end face of the damping piston (22) is provided with a push rod that contacts the inner wall of the buffer ring (5). The upper end of the inner wall of the buffer ring (5) is provided with a conical buffer surface (34). A return spring (23) is provided between the damping piston (22) on the outer periphery of the push rod and the step in the piston cavity.

2. The anti-impact spring-loaded safety valve according to claim 1, characterized in that: A core column (17) is installed in the cylindrical hole of the guide column on the back of the recoil disc (4) by a fixing ring (18). The damping cavity (33) and the damping piston (22) are set in the core column (17). The return spring (23) is installed between the damping piston (22) and the inner wall of the cylindrical hole of the recoil disc (4).

3. The anti-impact spring-loaded safety valve according to claim 2, characterized in that: in A steel ball (24) is placed between the push rod and the inner wall of the buffer ring (5). The steel ball (24) is placed in the radial hole between the inner wall of the cylindrical hole of the backflush plate (4) and the outer cylindrical surface.

4. The anti-impact spring-loaded safety valve according to claim 1, 2, or 3, characterized in that: The upper end of the buffer ring (5) has a guide cylinder that extends upward and guides the outer circular surface of the guide sleeve (7); there is a radial limiting step between the conical buffer surface (34) and the inner wall of the guide cylinder that cooperates with the lower end face of the guide sleeve (7); there is a buffer groove (21) between the lower inner hole of the guide sleeve (7) and the outer circular surface of the guide post of the backflush plate (4).

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