A self-tightening sealing stop valve

Abstract

The present invention discloses a self-tightening stop valve, comprising a valve body, a valve stem, a valve disc and a valve cover, wherein the valve disc is fixed at one end of the valve stem, a medium flow channel is arranged in the valve body, the valve disc is used to seal the medium flow channel, a valve disc welding sealing block has a first sealing surface and a second sealing surface, a valve seat is arranged in the valve body, the valve seat and the sealing block are matched and arranged, and have a sealing sub-surface 1 and a sealing sub-surface 2, the first sealing surface and the sealing sub-surface 1 bevel cooperate, and the second sealing surface and the sealing sub-surface 2 are arranged coaxially with the valve disc; the stop valve of the present invention avoids the damage of flash cavitation to the main sealing structure by arranging a double sealing structure that is opened in sequence, and the arc concave plate further arranged can improve the strength of the sealing effect, and the present invention improves the continuous effectiveness of the seal and prolongs the practical life of the valve by transferring the seal to release the damaged part.

Description

Technical Field

[0001] The invention relates to the technical field of valves, and in particular to a self-tightening sealing stop valve. Background Art

[0002] At present, the well-known stop valve includes a valve body, including a valve body, a liquid inlet chamber and a liquid outlet chamber are arranged in the valve body, a valve disc is arranged in the valve body, the valve disc is connected to the valve shaft, the valve shaft extends into the liquid outlet chamber and its end is connected to the valve disc, and the sealing control is achieved by driving the valve disc to rise and fall. The stop valve is characterized by a simple structure, a sealing surface that is not easy to wear, and a good sealing effect.

[0003] The sealing principle of the stop valve is to rotate the valve shaft so that the sealing end face of the valve plate cooperates with the sealing surface of the valve body to achieve sealing. In the prior art, there are two ways to enhance the sealing performance. One is to enhance the continuous sealing on the basis of sealing to improve the effect of long-term sealing; the other is to prevent the sealing surface from being damaged by design protection:

[0004] For example, Chinese patent: CN201610063336.1 self-sealing stop valve discloses a self-sealing stop valve, which uses medium pressure to compress and deform the elastic sealing layer on the valve plate to enhance the sealing performance; the elastic sealing layer on the sealing end face is compressed and deformed by the fluid pressure and the weight of the valve plate to achieve sealing, that is, blocking the liquid inlet cavity and the liquid outlet cavity. In addition, the existing stop valve also has the problem that the conical sealing surface is cavitated or directly eroded by the medium when opening and closing, and the static medium forms a sudden impact force after releasing the seal, which seriously erodes and corrodes the sealing surface. In particular, high-temperature medium is prone to flash cavitation, which makes the sealing effect worse and worse. Summary of the invention

[0005] In view of the prior art, the purpose of the present invention is to provide an electric self-sealing stop valve, which reduces direct damage to the sealing surface when the valve is opened and closed through a unique sealing structure setting, and at the same time has a long-term continuous sealing function.

[0006] In order to achieve the above objectives, the technical solution adopted by the present invention is: a self-tightening stop valve, comprising a valve body, a valve stem, a valve disc and a valve cover, the valve disc is fixed at one end of the valve stem, a medium flow channel is arranged in the valve body, the valve disc is used to seal the medium flow channel, the valve disc is cylindrical, and a sealing block is welded at the bottom thereof, the sealing block has a first sealing surface and a second sealing surface, a valve seat is arranged in the valve body, the valve seat is matched with the sealing block, and has a sealing sub-surface 1 corresponding to the first sealing surface and a sealing sub-surface 2 corresponding to the second sealing surface, the medium flow channel is coaxially arranged with the cylindrical valve disc, and the first sealing surface and the sealing sub-surface 1 are matched with the inclined surface, and the second sealing surface and the sealing sub-surface 2 are coaxially arranged with the valve disc.

[0007] As a further configuration of the above scheme, the second sealing surface and the second sealing sub-surface release the abutment seal after the first sealing surface and the first sealing sub-surface when the valve is open, and the second sealing surface and the second sealing sub-surface perform abutment seal before the first sealing surface and the first sealing sub-surface when the valve is closed.

[0008] As a further configuration of the above solution, the thickness of the annular convex ring formed by the sealing auxiliary surface 1 and the sealing auxiliary surface 2 is greater than the width of the annular groove formed by the first sealing surface and the second sealing surface.

[0009] As a further configuration of the above scheme, the sealing block is made of elastic material, and the valve disc is also provided with an arc-shaped concave plate, which is disc-shaped and has an arc surface on the edge, and the maximum diameter of the arc-shaped concave plate is larger than the inner diameter of the valve seat.

[0010] As a further configuration of the above scheme, the inner hole of the valve seat has a bell-mouth curvature, and its inclination angle is set to shrink from the liquid inlet end to the outlet side. The maximum distance that the arc concave plate protrudes relative to the valve disc is the same as the front end of the second sealing surface on the sealing block.

[0011] As a further configuration of the above scheme, a throttling cylinder is further arranged in the valve body, and the throttling cylinder is sleeved outside the valve seat and the valve disc. An actuator for driving the valve stem is arranged at the other end of the valve stem.

[0012] As a further configuration of the above scheme, the valve seat includes a ring plate and a sealing gasket clamped between the ring plate and the valve body, a sealing component is arranged on the ring plate, the sealing sub-surface one and the sealing sub-surface two are arranged on the sealing component, and the end of the throttling cylinder abuts against the sealing component, and forms a static sealing structure with the valve body clamping the sealing component, the ring plate and the sealing gasket.

[0013] Beneficial effect: The stop valve of the present invention is provided with a double sealing structure that is opened in sequence. After the main sealing structure is opened, the valve is still in a sealed state. After the secondary sealing structure is opened, the valve opens, and the main sealing structure is away from the valve seat at this time, thereby avoiding the occurrence of flash cavitation and damage to the sealing surface of the main sealing structure. The arc concave plate further provided can enhance the strength of the sealing effect. The present invention improves the continuous effectiveness of the seal by transferring the seal to release the damaged part, thereby extending the practical life of the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the valve structure of the present invention.

[0015] Figure 2 It is a schematic cross-sectional view of the valve of the present invention.

[0016] Figure 3 For the present invention Figure 2Partial enlarged image.

[0017] Figure 4 It is a schematic diagram of the curved concave plate of the present invention.

[0018] Figure numerals: 1. valve body; 2. valve stem; 3. valve disc; 31. sealing block; 32. first sealing surface; 33. second sealing surface; 38. annular groove; 39. annular convex ring; 4. valve cover; 5. medium flow channel; 6. valve seat; 61. sealing sub-surface 1; 62. sealing sub-surface 2; 65. ring plate; 66. sealing short piece; 67. sealing component; 8. arc surface concave plate; 88. actuator; 9. throttling cylinder. DETAILED DESCRIPTION

[0019] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0020] like Figure 1-4 A self-tightening stop valve shown in the figure comprises a valve body 1, a valve stem 2, a valve disc 3 and a valve cover 4, the valve disc 3 is fixed at one end of the valve stem 2, a medium flow channel 5 is arranged in the valve body 1, the valve disc 3 is used to seal the medium flow channel 5, the valve disc 3 is cylindrical, and a sealing block 31 is welded at the bottom thereof, the sealing block 31 has a first sealing surface 32 and a second sealing surface 33, a valve seat 6 is arranged in the valve body 1, the valve seat 6 is matched with the sealing block 31, and has a sealing sub-surface 1 61 corresponding to the first sealing surface 32 and a sealing sub-surface 2 62 corresponding to the second sealing surface 33, the medium flow channel 5 is arranged coaxially with the cylindrical valve disc 3, and the first sealing surface 32 and the sealing sub-surface 1 61 are matched with the inclined surfaces, and the second sealing surface 33 and the sealing sub-surface 2 62 are arranged coaxially with the valve disc 3.

[0021] As a further configuration of the above scheme, when the second sealing surface 33 and the second sealing sub-surface 62 are in the valve open state, the abutment seal is released later than the first sealing surface 32 and the first sealing sub-surface 61, and when the second sealing surface 33 and the second sealing sub-surface 62 are in the valve closed state, the abutment seal is performed before the first sealing surface 32 and the first sealing sub-surface 61.

[0022] Through the above-mentioned structural arrangement, in the open and closed state of the valve, when the valve is opened, when the first sealing surface 32 and the sealing sub-surface 1 61 are released from the seal, the second sealing surface 33 and the sealing sub-surface 2 62 are still in a basically sealed state. Therefore, in the entire process of opening the valve, the medium is finally sealed, and it is mainly the sealing structure of the second sealing surface 33 and the sealing sub-surface 2 62 that will cause flash cavitation, while the first sealing surface 32 and the sealing sub-surface 1 61 mainly provide complete sealing for the closed valve state. The present invention improves the continuous effectiveness of the seal and extends the practical life of the valve by transferring the seal to release the damaged part.

[0023] As a further configuration of the above solution, the thickness of the annular convex ring 39 formed by the sealing auxiliary surface 1 61 and the sealing auxiliary surface 2 62 is greater than the width of the annular groove 38 formed by the first sealing surface 32 and the second sealing surface 33 .

[0024] As a further configuration of the above scheme, the sealing block 31 is made of elastic material, and a curved concave plate 8 is also provided on the valve disc 3. The curved concave plate 8 is disc-shaped and has a circular arc surface on the edge. The maximum diameter of the curved concave plate 8 is larger than the inner diameter of the valve seat 6.

[0025] As a further configuration of the above scheme, the inner hole of the valve seat 6 has a bell-mouth curvature, and its inclination angle is set to shrink from the liquid inlet end to the outlet side. The maximum distance that the arc concave plate 8 protrudes relative to the valve disc 3 is the same as the front end of the second sealing surface 33 on the sealing block 31.

[0026] As a further configuration of the above scheme, a throttling cylinder 9 is further provided in the valve body 1 , and the throttling cylinder 9 is sleeved outside the valve seat 6 and the valve disc 3 . The other end of the valve stem 2 is provided with an actuator 88 for driving the valve stem 2 .

[0027] As a further configuration of the above scheme, the valve seat 6 includes a ring plate 65 and a sealing gasket 66 clamped between the ring plate 65 and the valve body 1, a sealing component 67 is arranged on the ring plate 65, the sealing sub-surface 1 62 and the sealing sub-surface 2 62 are arranged on the sealing component 67, and the end of the throttling cylinder 9 abuts against the sealing component 67, and forms a static sealing structure with the valve body 1 by clamping the sealing component 67, the ring plate 65 and the sealing gasket 66.

[0028] In the present invention, the valve seat 6 is pressed and fixed by the throttling cylinder 9 in the direction of the valve cover 4. When disassembling, all the internal components can be disassembled by removing the valve cover 4 from the top, which is very convenient. When fixing, the components can be put in one by one. The advantage of this fixing method is that it is not only convenient for processing and production, but also the sealing structure can be disassembled and replaced, which is convenient for regular maintenance and repair.

[0029] Working principle: The valve of the present invention is provided with at least two sealing surfaces, a first sealing surface 32 and a sealing sub-surface 1 61 with inclined surfaces abutting against each other, forming a main sealing structure, and a second sealing surface 33 and a sealing sub-surface 2 62 forming a secondary auxiliary sealing structure. The advantage of the above double seal is that one of the situations in which the sealing surface of the prior art produces a loose seal is that the sealing surface is eroded by the medium and the flash cavitation caused by the instantaneous medium pressure difference when the seal is released. When the valve of the present invention is in the valve disc 3 away from the valve seat 6 to open the valve, when the first sealing surface 32 and the sealing sub-surface 1 61 are released from separation, the second sealing surface 33 and the sealing sub-surface 2 62 still maintain a sealed state (it does not matter if the seal is not tight and there are small holes), and when the second sealing surface 33 and the sealing sub-surface 2 62 are released from the sealed state, the first sealing surface 32 and the sealing sub-surface 1 61 are already quite far apart, so that the flash cavitation is not easy to damage the sealing surface, and the pointed cone of the valve disc 3 and the sealing sub-surface 1 61 on the valve seat 6 are open to the outside, which also reduces the direct erosion of the sealing surface by the medium;

[0030] In a further configuration, a curved concave plate 8 is provided on the valve disc 3, and the curved plate is used to buffer the medium directly rushing from the front, so that the medium flows to both sides of the valve disc 3 under the action of the curved plate, reducing the scouring force of the medium and further protecting the sealing surface structure. In addition, the sealing structure of the valve seat of this scheme is set to an elastic material, and the curved concave plate 8 is interference-fitted in the sealing state. Figure 3 As shown, there is a certain degree of squeezing on the valve seat sealing pair, causing it to deform. In addition, under the pressure of the medium, the valve disc 3 may move slightly backward, resulting in a loose seal. The arc-surface concave plate 8 of the present invention is designed to push the deformed valve seat sealing structure to squeeze it so that it is close to the sealing surface when it moves slightly backward, thereby forming a technical structural design of a self-tightening seal.

[0031] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A self-tightening stop valve, comprising a valve body (1), a valve stem (2), a valve flap (3) and a valve cover (4), wherein the valve flap (3) is fixed to one end of the valve stem (2), a medium flow channel (5) is arranged in the valve body (1), and the valve flap (3) is used to seal the medium flow channel (5), characterized in that: The valve flap (3) is cylindrical, and a sealing block (31) is welded to its bottom. The sealing block (31) has a first sealing surface (32) and a second sealing surface (33). A valve seat (6) is arranged in the valve body (1). The valve seat (6) is matched with the sealing block (31) and has a first sealing surface (61) corresponding to the first sealing surface (32) and a second sealing surface (62) corresponding to the second sealing surface (33). The medium flow channel (5) is coaxially arranged with the cylindrical valve flap (3), and the first sealing surface (32) and the first sealing surface (61) are matched with each other in an inclined manner. The second sealing surface (33) and the second sealing surface (62) are coaxially arranged with the valve flap (3). The second sealing surface (33) and the second sealing surface (62) release the abutment seal after the first sealing surface (32) and the first sealing surface (61) when the valve is in the open state, and perform abutment seal before the first sealing surface (32) and the first sealing surface (61) when the second sealing surface (33) and the second sealing surface (62) are in the closed state; the thickness of the annular convex ring (39) formed by the first sealing surface (61) and the second sealing surface (62) is greater than the width of the annular groove (38) formed by the first sealing surface (32) and the second sealing surface (33); the valve flap (3) is also provided with an arc-shaped concave plate (8), the arc-shaped concave plate (8) is in the shape of a disk, and has an arc surface on the edge; the maximum diameter of the arc-shaped concave plate (8) is greater than the inner diameter of the valve seat (6); the inner hole of the valve seat (6) has a bell-mouth curvature, and its inclination angle is set to shrink from the liquid inlet end to the outlet side; the arc-shaped concave plate (8) The maximum distance of the protrusion relative to the valve disc (3) is the same as the front end of the second sealing surface (33) on the sealing block (31); the valve seat (6) comprises a ring plate (65) and a sealing gasket (66) clamped between the ring plate (65) and the valve body (1); a sealing component (67) is arranged on the ring plate (65); and the sealing auxiliary surface 1 (61) and the sealing auxiliary surface 2 (62) are arranged on the sealing component (67).

2. A self-tightening stop valve according to claim 1, characterized in that: The sealing block (31) is made of elastic material.

3. A self-tightening stop valve according to claim 1, characterized in that: A throttling cylinder (9) is also provided in the valve body (1), and the throttling cylinder (9) is sleeved outside the valve seat (6) and the valve disc (3). An actuator (88) for driving the valve stem (2) is provided at the other end of the valve stem (2).

4. A self-tightening stop valve according to claim 3, characterized in that: The end of the throttling cylinder (9) abuts against the sealing component (67), and clamps the sealing component (67), the ring plate (65) and the sealing gasket (66) with the valve body (1) to form a static sealing structure.

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