A buffer spring type soft seal safety valve

Abstract

The present invention relates to a buffer spring type soft sealing safety valve, comprising a valve body, a valve seat, a valve disc, a recoil disc, a guide sleeve, a valve cover, and a pressure setting device, and is characterized in that a buffer device is arranged between the guide sleeve and the recoil disc, so as to reduce the closing speed during the valve disc returning to its seat, reduce the impact force between the valve disc sealing surface and the valve seat sealing surface, effectively prevent the valve disc sealing surface from being damaged by impact during the closing process, and improve the sealing performance and product service life.

Description

Technical Field

[0001] The invention belongs to the field of valves, and in particular relates to a spring type soft sealing safety valve. Background Art

[0002] When traditional safety valves are used in working conditions with high sealing requirements, they often adopt a soft sealing structure, with the valve seat sealing surface made of metal material and the valve disc sealing surface made of non-metallic material to meet the high sealing requirements. Its disadvantages are: when the valve disc is opened and then closed, the valve disc sealing surface quickly impacts the valve seat sealing surface, with a large impact force, and the valve disc sealing surface is easily damaged by frequent opening and closing, causing the valve to lose its sealing function and a short product life. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention provides a buffer spring type soft sealing safety valve which reduces the closing speed of the valve disc when closing, reduces the impact force when the valve disc is closed, has reliable sealing performance and long service life.

[0004] The technical solution of the present invention is:

[0005] A buffer spring type soft seal safety valve comprises a valve body, a valve seat, a valve disc, a recoil disc, a guide sleeve, a valve cover and a pressure setting device. The valve disc is fixedly mounted on the lower end surface of the recoil disc and the metal sealing surface of the valve seat by a soft sealing gasket to form a soft seal auxiliary structure. The guide column on the upper part of the recoil disc is movably matched with the guide hole of the guide sleeve. The pressure setting device comprises a valve stem, a spring and an adjusting screw sleeve. The lower end of the valve stem is pressed against the back center of the recoil disc. The spring is mounted between the upper and lower spring seats on the valve stem. The adjusting screw sleeve is threadedly mounted on the valve cover, and its lower end is pressed against the upper end surface of the upper spring seat. The characteristic of the adjusting screw sleeve is that a buffer device is arranged between the guide sleeve and the recoil disc. The buffer device is composed of a buffer block movably installed in the inner cavity of the guide column, a pressure chamber is formed between the left end surface of the buffer block and the inner cavity of the guide column, and a reset spring is installed between the limit step arranged on the lower side of the right end and the limit block on the right side of the inner cavity of the guide column; the pressure chamber is connected with the outlet cavity through the upper pressure-introducing hole in the buffer block, the middle pressure-introducing hole and the lower pressure-introducing hole on the guide column, a one-way valve is arranged between the middle pressure-introducing hole and the lower pressure-introducing hole on the guide column, and a pressure relief hole connecting the middle pressure-introducing hole and the outlet cavity is arranged on the recoil disk; an upper buffer slope is arranged on the upper side of the lower limit step at the right end of the buffer block, and a lower buffer slope cooperating with the upper buffer slope on the buffer block is arranged on the guide sleeve.

[0006] Preferably, the lower buffer slope is arranged on the lower bottom surface of the buffer window on the right side of the guide sleeve.

[0007] Preferably, an anti-rotation rod and an anti-rotation groove that cooperate with each other are provided between the outer circumferential surface of the guide post of the recoil disk and the guide sleeve.

[0008] Compared with the prior art, the present invention has the following beneficial effects: a buffer device is arranged between the guide sleeve and the recoil disk, the closing speed is reduced during the valve disc returning to its seat, the impact force between the valve disc sealing surface and the valve seat sealing surface is reduced, the valve disc sealing surface is effectively prevented from being damaged by impact during the closing process, and the sealing performance and product service life are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural schematic diagram of the present invention.

[0010] Figure 2 The present invention Figure 1 Schematic diagram of the structure of the buffer device between the recoil disk and the guide sleeve when the valve is open.

[0011] Figure 3 The present invention Figure 1 Schematic diagram of the structure of the recoil disk and buffer device when the valve is closed.

[0012] Figure 4 The present invention Figure 1 Schematic diagram of the structure of the middle guide sleeve.

[0013] In the figure: 1 valve body, 2 valve seat, 3 adjusting ring, 4 recoil disc, 5 anti-rotation rod, 6 anti-rotation groove, 7 guide sleeve, 8 valve cover, 9 valve stem, 10 spring, 11 upper spring seat, 12 adjusting screw sleeve, 13 valve cap, 14 cushion block, 15 outlet cavity, 16 inlet cavity, 17 guide column, 18 buffer window, 19 buffer block, 20 return spring, 21 limit block, 22 plugging, 23 pressure relief hole, 24 return spring, 25 one-way valve disc, 26 lower pressure-introducing hole, 27 valve disc, 28 middle pressure-introducing hole, 29 sealing surface, 30 upper pressure-introducing hole, 31 pressure cavity, 32 upper buffer slope, 33 lower buffer slope. Implementation

[0014] like Figure 1The buffer spring type soft seal safety valve shown in the figure comprises a valve body 1, a valve seat 2, a valve disc 27, a recoil disc 4, a guide sleeve 7, a valve cover 8, and a pressure setting device. The valve seat 2 is installed in the inlet cavity 16 of the valve body 1, and a metal sealing surface is provided at its upper end. An adjusting ring 3 is arranged outside the metal sealing surface. The opening height of the valve disc 27 is adjusted by adjusting the axial position of the adjusting ring 3. The valve disc 27 is made of fluoroplastic material and is fixedly installed on the lower end surface of the recoil disc 4. A sealing surface 29 that cooperates with the metal sealing surface of the valve seat is arranged in its lower plane. The guide column 17 on the upper part of the recoil disc 4 is movably matched with the guide hole of the guide sleeve 7. The pressure setting device includes a valve stem 9, a spring 10, and an adjusting screw sleeve 12. The spring 10 is installed between the upper and lower spring seats on the valve stem 9. The adjusting screw sleeve 12 is threadedly installed on the valve cover 8, and its lower end is pressed against the upper end surface of the upper spring seat 11. A valve cap 13 is installed on the upper end of the valve cover 8 to prevent dust from entering the spring cavity. The device is characterized in that a buffer device is arranged between the guide sleeve 7 and the recoil disc 4, and the buffer device is composed of a buffer block 19 movably installed in the inner cavity of the guide column 17. A pressure cavity 31 is formed between the left end surface of the buffer block 19 and the inner cavity of the guide column 17, and a limit step arranged on the lower side of the right end is connected to the guide column 17. A return spring 20 is installed between the limit blocks 21 on the right side of the inner cavity; the pressure chamber 31 is connected to the outlet cavity 15 through the upper pressure-introducing hole 30 in the buffer block 19, the middle pressure-introducing hole 28 and the lower pressure-introducing hole 26 on the guide column 17, and a one-way valve is arranged between the middle pressure-introducing hole 28 and the lower pressure-introducing hole 26 on the guide column 17. The one-way valve is composed of a one-way valve disc 25 and a return spring 24. A conical sealing surface is arranged on the lower end surface of the one-way valve disc 25, and the sealing surface on the step in the lower pressure-introducing hole 26 cooperates with each other to form a sealing pair. The return spring 24 is installed between the upper end surface of the one-way valve disc 25 and the lower end surface of the plug 22, and the plug 22 Installed in the recoil disc 4 just above the lower pressure-introducing hole 26, when the valve disc 27 is closed, the one-way valve disc 25 is pushed by the return spring 24 to seal with the sealing surface on the step in the lower pressure-introducing hole 26. When the valve disc 27 is opened, the medium pressure pushes the one-way valve disc 25 to overcome the elastic push of the return spring 24 to open. The recoil disc 4 is provided with a pressure relief hole 23 connecting the middle pressure-introducing hole 28 and the outlet cavity 15. After the one-way valve disc 25 is closed, the medium in the pressure chamber 31 is discharged to the outlet cavity 15 through the pressure relief hole 23. A cushion block 14 is arranged at the center of the back of the recoil disc 4 to facilitate the processing of the vertical hole of the middle pressure-introducing hole 28, such as Figure 3 As shown, the lower end of the valve stem 9 presses against the center of the upper end surface of the cushion block 14; an upper buffer slope 32 is provided on the upper side of the lower limit step at the right end of the buffer block 19, and a lower buffer slope 33 is provided on the guide sleeve 7 to cooperate with the upper buffer slope 32 on the buffer block 19. When the valve flap 27 is opened, the recoil disc 4 rises, and the buffer block 19 moves rightward under the pressure in the pressure chamber 31, and its upper buffer slope 32 is inserted into the lower buffer slope 33 on the guide sleeve 7, as shown in FIG. Figure 2As shown; when the valve flap 27 is closed, the buffer block 19 moves from the lower buffer slope 33 to the lower left, and at the same time, the medium pressure in the pressure chamber 31 has a damping effect on the leftward movement of the buffer block 19, thereby reducing the closing speed of the valve flap 27 and reducing the impact between the valve flap 27 and the valve seat 2.

[0015] The lower buffer slope 33 is arranged on the lower bottom surface of the buffer window 18 on the right side of the guide sleeve 7. Figure 4 shown.

[0016] An anti-rotation rod 5 and an anti-rotation groove 6 that cooperate with each other are provided between the outer circumferential surface of the guide column 17 of the recoil disc 4 and the guide sleeve 7 to prevent the recoil disc 4 from rotating when it moves up and down.

[0017] Working process:

[0018] Opening process: when the medium pressure in the inlet chamber 16 reaches the set pressure value, the upward force of the medium on the valve disc 27 is greater than the downward force of the spring 10 on the valve disc 27 through the valve stem 9, the valve disc 27 and the recoil disk 4 move upward, and the valve opens. At this time, the medium in the outlet chamber 15 pushes the one-way valve disc 25 upward, the lower pressure-introducing hole 26 is connected to the middle pressure-introducing hole 28, and the medium enters the pressure chamber 31 through the lower pressure-introducing hole 26, the middle pressure-introducing hole 28 and the upper pressure-introducing hole 30 in turn. The medium in the pressure chamber 31 pushes the buffer block 19 to move right, and the right part of the buffer block 19 enters the buffer window 18, and the upper buffer slope 32 is pressed and contacted with the lower buffer slope 33.

[0019] Closing process: when the medium pressure in the inlet chamber 16 reaches the return seat pressure value, the upward force of the medium on the valve disc 27 is less than the downward force of the spring 10 on the valve disc 27 through the valve stem 9, and the valve disc 27 and the recoil disk 4 move downward. At this time, the one-way valve disc 25 moves downward and closes under the action of the return spring 24, and the lower pressure-introducing hole 26 is cut off from the middle pressure-introducing hole 28. At the same time, the buffer block 19 moves to the lower left along the lower buffer slope 33 under the downward push of the return spring 20 and the valve stem 9. At this time, the medium in the pressure chamber 31 is compressed and slowly released from the pressure relief hole 23, which has a damping effect on the leftward movement of the buffer block 19, slowing down the leftward movement speed of the buffer block 19, and at the same time slowing down the downward movement speed of the valve disc 27 and the recoil disk 4, reducing the impact force of the sealing surface of the valve disc 27 on the sealing surface of the valve seat 2, and preventing the sealing surface of the valve disc 27 from being damaged by the impact.

Claims

1. A buffer spring type soft seal safety valve, comprising a valve body (1), a valve seat (2), a valve disc (27), a recoil disc (4), a guide sleeve (7), a valve cover (8), and a pressure setting device, wherein a guide post (17) on the upper part of the recoil disc (4) is movably matched with a guide hole of the guide sleeve (7); wherein: A buffer device is provided between the guide sleeve (7) and the recoil plate (4), the buffer device comprising a buffer block (19) movably mounted in the inner cavity of the guide column (17); a pressure chamber (31) is formed between the left end surface of the buffer block (19) and the inner cavity of the guide column (17); a return spring (20) is installed between a limit step provided at the lower side of the right end and a limit block (21) on the right side of the inner cavity of the guide column (17); the pressure chamber (31) is opened through an upper pressure-introducing hole (30) in the buffer block (19) and a middle pressure-introducing hole on the guide column (17). The middle pressure-introducing hole (28) and the lower pressure-introducing hole (26) are connected to the outlet chamber (15) of the valve body (1); a one-way valve is arranged between the middle pressure-introducing hole (28) and the lower pressure-introducing hole (26) on the guide column (17); a pressure relief hole (23) connecting the middle pressure-introducing hole (28) and the outlet chamber (15) is arranged on the recoil disc (4); an upper buffer slope (32) is arranged on the upper side of the limiting step at the right end of the buffer block (19); and a lower buffer slope (33) is arranged on the guide sleeve (7) and cooperates with the upper buffer slope (32) on the buffer block (19).

2. The buffer spring type soft seal safety valve according to claim 1 is characterized in that: The lower buffer slope (33) is arranged on the bottom surface of the buffer window (18) on the right side of the guide sleeve (7).

3. The buffer spring type soft seal safety valve according to claim 1 or 2, characterized in that: An anti-rotation rod (5) and an anti-rotation groove (6) that cooperate with each other are provided between the outer circumferential surface of the guide column (17) of the recoil disc (4) and the guide sleeve (7).

Images