Pneumatic stop valve

Abstract

The utility model discloses a pneumatic stop valve which comprises a valve body, a valve cover installed on the valve body, a valve clack installed in the valve body, a valve rod installed on the valve cover and connected with the valve clack and a pneumatic actuator installed on the valve cover and used for driving the valve rod to move. A sealing face matched with the valve seat to form sealing is formed on the replacement sealing part, the replacement sealing part is in threaded connection with the main body part, and when the replacement sealing part is fixed to the main body part, a sealing structure used for sealing the threaded connection position is formed between the replacement sealing part and the main body part. A detachable non-return assembly used for limiting rotation of the replacement sealing part is arranged between the main body part and the replacement sealing part. The butterfly valve has the following advantages and effects that the sealing surface of the valve clack can be conveniently replaced, so that the later maintenance cost is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to a valve, in particular to a pneumatic stop valve. BACKGROUND

[0002] The stop valve is also called the cut-off valve, and is one of the most widely used valves, and is popular because of small friction between sealing surfaces in the opening and closing process, durability, small opening height, easy manufacturing, and convenient maintenance, and is suitable for medium and low pressure and high pressure. The closing principle of the stop valve is that the valve stem pressure makes the valve disc sealing surface and the valve seat sealing surface tightly adhere to prevent medium flow.

[0003] Because the closing sealing mechanism of the stop valve is realized by the valve stem pressure, this sealing method is easy to cause the wear of the valve disc sealing surface. In addition, when the valve is in the open state, the sealing surface of the valve disc directly contacts the fluid medium, and is further subjected to the scouring of the fluid. Therefore, the valve disc needs to be replaced regularly. In order to reduce the replacement cost of the valve disc, a valve disc structure design with a replaceable sealing surface has appeared on the market to reduce maintenance cost. SUMMARY

[0004] The utility model aims at providing a pneumatic stop valve which can realize convenient replacement of the valve disc sealing surface to reduce the later maintenance cost.

[0005] The above technical purpose of the utility model is realized by the following technical scheme: a pneumatic stop valve, comprising a valve body, a valve cover installed on the valve body, a valve disc installed in the valve body, a valve stem installed on the valve cover and connected with the valve disc, and a pneumatic actuator installed on the valve cover and used for driving the valve stem to move, the valve disc comprising a main body part and a replaceable sealing part, the replaceable sealing part being formed with a sealing surface matched with the valve seat to constitute a seal, the replaceable sealing part being threadedly connected with the main body part, a sealing structure for sealing the threaded connection part being formed between the replaceable sealing part and the main body part when the replaceable sealing part is fixed to the main body part, and a detachable reverse stopping assembly being arranged between the main body part and the replaceable sealing part and used for limiting the rotation of the replaceable sealing part.

[0006] By adopting the above technical scheme, the replaceable sealing part is threadedly connected with the main body part, and then the detachable reverse stopping assembly is arranged to limit the rotation of the threaded connection part, so as to achieve the purpose of reverse stopping and anti-loosening, and to ensure the reliability and sealing performance of the detachable connection structure. The detachable reverse stopping assembly has the detachable feature, so that the setting structure does not interfere with the replacement operation of the replaceable sealing part, so as to realize convenient replacement of the valve disc sealing surface and reduce the later maintenance cost.

[0007] Further, the detachable reverse prevention assembly comprises a reverse prevention structure and a detachable structure for controlling the reverse prevention structure to switch between a reverse prevention state and a non-reverse prevention state.

[0008] By adopting the above technical scheme, the detachable structure controls the reverse prevention structure to switch between the reverse prevention state and the non-reverse prevention state, thereby achieving the double effects of reverse prevention and detachability.

[0009] Further, the reverse prevention structure comprises a reverse prevention groove arranged on the replacement sealing part and a reverse prevention rod inserted into the reverse prevention groove, and the reverse prevention groove is arranged around the center of the valve rod.

[0010] By adopting the above technical scheme, the reverse prevention rod is inserted into the reverse prevention groove to limit the rotation of the replacement sealing part in the rotation direction, thereby achieving the purpose of reverse prevention.

[0011] Further, the detachable structure is an elastic piece connecting the reverse prevention rod and the main body part.

[0012] By adopting the above technical scheme, the elastic piece causes the reverse prevention rod to elastically deform, thereby changing the position of the reverse prevention rod and controlling whether the reverse prevention rod is inserted into the reverse prevention groove.

[0013] Further, the elastic piece is a reverse prevention spring.

[0014] By adopting the above technical scheme, the reverse prevention spring has good circumferential limiting force and good axial elastic deformation force, can well limit the rotation of the replacement sealing part and facilitate the control of whether the reverse prevention rod is inserted into the reverse prevention groove, can be directly purchased as a finished product, and has a relatively low price.

[0015] Further, the sealing structure comprises a sealing block integrally connected to the replacement sealing part and a sealing ring arranged between the sealing block and the main body part, the sealing block is located below the main body part, and the sealing ring is coaxially arranged with the valve rod.

[0016] By adopting the above technical scheme, the replacement sealing part and the main body part can drive the sealing block to extrude the sealing ring during the threaded fastening process, thereby achieving a more excellent sealing effect.

[0017] Further, the replacement sealing part comprises a butt joint part threadedly connected with the main body part and a sealing hard part having the sealing surface, the sealing hard part is sleeved on the butt joint part and is tightly fixed with the butt joint part, the main body part is integrally connected with the valve rod, and the reverse prevention groove is arranged on the butt joint part.

[0018] By adopting the technical scheme, the main body part and the valve rod are connected in an integrated mode to improve the structural strength, so that the structure can better bear the force applied by the fluid medium. The threaded connection structure is used to separately detach the replaceable sealing part, so that the detachable operation of the abutting part and the sealing hard part can be performed separately and is not interfered by other components, so that the detachable operation is facilitated and the operation is more convenient. The thermal expansion and cold shrinkage are used to realize the interference fit of the abutting part and the sealing hard part, so as to achieve the fixing purpose. The structure only needs to replace the sealing hard part, so that the maintenance cost is further reduced. The reverse stop groove is arranged on the abutting part with low hardness, so that the processing cost and difficulty are reduced and the processing efficiency is improved.

[0019] Further, when the sealing hard part is fixed to the abutting part, the abutting part is provided with a limiting ring limiting the movement of the sealing hard part away from the valve seat.

[0020] By adopting the technical scheme, the force on the sealing hard part when the valve is closed can be better borne, so as to ensure the stability of the structure.

[0021] Further, the diameter of the limiting ring is smaller than the outer diameter of the sealing hard part.

[0022] By adopting the technical scheme, the sealing hard part is provided with a force applying position for disassembly, so that the disassembly operation of the sealing hard part is more convenient.

[0023] In summary, the utility model has the following beneficial effects: the utility model can realize convenient replacement of the sealing surface of the valve disc, so as to reduce the maintenance cost in the later period. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a structure schematic view of an embodiment;

[0025] Figure 2 It is a local structure schematic view of an embodiment.

[0026] In the drawing: 1, valve body; 2, valve cover; 3, valve disc; 31, main body part; 32, abutting part; 33, sealing hard part; 4, valve rod; 5, pneumatic actuator; 6, sealing surface; 7, detachable reverse stop assembly; 71, reverse stop groove; 72, reverse stop rod; 73, elastic member; 81, sealing block; 82, sealing ring; 9, limiting ring. DETAILED DESCRIPTION

[0027] The utility model will be further described in detail below with reference to the drawings.

[0028] REFERENCE Figure 1 and Figure 2The utility model provides a kind of pneumatic stop valve, including valve body 1, the bonnet 2 of fixed installation in valve body 1, the valve clack 3 of installation in valve body 1, the valve stem 4 of installation in bonnet 2 and connect valve clack 3 and the pneumatic actuator 5 of fixed installation in bonnet 2 and for driving valve stem 4 movement.Valve clack 3 includes main body part 31 and replacement seal part, and sealing surface 6 is formed on replacement seal part and cooperates with valve seat to constitute seal, and replacement seal part is threadedly connected with main body part 31.When replacement seal part is fixed to main body part 31, sealing structure for sealing threaded connection is formed between replacement seal part and main body part 31;Between main body part 31 and replacement seal part, detachable reverse stop component 7 for limiting rotation of replacement seal part is equipped.Pneumatic actuator 5 is cylinder fixedly arranged on bonnet 2, and the telescopic rod of cylinder is fixedly connected with valve stem 4.

[0029] Replacement seal part includes docking part 32 threadedly connected with main body part 31 and sealing hard part 33 with the sealing surface 6, and sealing hard part 33 is sleeved on docking part 32 and fixedly connected with docking part 32 by interference fit, and main body part 31 is integrally connected with valve stem 4.The material of sealing hard part 33 is hard alloy steel or nickel-based alloy.

[0030] Detachable reverse stop component 7 includes reverse stop structure and detachable structure for controlling reverse stop structure to switch between reverse stop state and non-reverse stop state.Reverse stop structure includes reverse stop groove 71 opened in docking part 32 and reverse stop rod 72 inserted into reverse stop groove 71, and several reverse stop grooves 71 are arranged around the center of valve stem 4.The detachable structure is elastic member 73 connecting reverse stop rod 72 and main body part 31, and the elastic member 73 is reverse stop spring, one end of which is fixedly connected with main body part 31 and the other end of which is integrally connected with reverse stop rod 72.

[0031] Sealing structure includes sealing block 81 integrally connected with docking part 32 and sealing ring 82 arranged between sealing block 81 and main body part 31, and sealing block 81 is located below main body part 31 and sealing ring 82 is coaxially arranged with valve stem 4, and sealing ring 82 is embedded in sealing block 81.When sealing hard part 33 is fixed to docking part 32, limiting ring 9 for limiting movement of sealing hard part 33 away from valve seat is integrally arranged on docking part 32, and the diameter of limiting ring 9 is smaller than the outer diameter of sealing hard part 33.

[0032] The specific embodiment is only the explanation of the utility model, and it is not the limitation of the utility model, and the modification without creative contribution can be made to the embodiment according to the need after reading the specification by the person skilled in the art, but as long as in the scope of the claims of the utility model, it is protected by the patent law.

Claims

1. A pneumatic stop valve comprising a valve body (1), a bonnet (2) mounted to the valve body (1), a valve disc (3) mounted in the valve body (1), a valve stem (4) mounted to the bonnet (2) and connected to the valve disc (3), and a pneumatic actuator (5) mounted to the bonnet (2) and used to drive the valve stem (4) to move, the valve disc (3) comprising a main body portion (31) and a replacement seal portion, a sealing surface (6) formed on the replacement seal portion to cooperate with a valve seat to form a seal, characterized in that: The replacement sealing part is threadedly connected with the main body part (31), a sealing structure for sealing the threadedly connected part is formed between the replacement sealing part and the main body part (31) when the replacement sealing part is fixed to the main body part (31), and a detachable reverse stopping assembly (7) for limiting rotation of the replacement sealing part is arranged between the main body part (31) and the replacement sealing part.

2. The pneumatic globe valve of claim 1, wherein: The detachable reverse stopping assembly (7) comprises a reverse stopping structure and a detachable structure for switching the reverse stopping structure between a reverse stopping state and a non-reverse stopping state.

3. The pneumatic globe valve of claim 2, wherein: The reverse stopping structure comprises a reverse stopping groove (71) arranged on the replacement sealing part and a reverse stopping rod (72) inserted into the reverse stopping groove (71), and the reverse stopping groove (71) is arranged around the center of the valve rod (4) in a circular manner.

4. The pneumatic globe valve of claim 3, wherein: The detachable structure is an elastic member (73) connecting the reverse stopping rod (72) and the main body part (31).

5. The pneumatic globe valve of claim 4, wherein: The elastic member (73) is a reverse stopping spring.

6. The pneumatic globe valve of claim 1, wherein: The sealing structure comprises a sealing block (81) integrally connected to the replacement sealing part and a sealing ring (82) arranged between the sealing block (81) and the main body part (31), the sealing block (81) is located below the main body part (31), and the sealing ring (82) is coaxially arranged with the valve rod (4).

7. The pneumatic globe valve of claim 3, wherein: The replacement sealing part comprises a butt joint part (32) threadedly connected with the main body part (31) and a sealing hard part (33) having the sealing surface (6), the sealing hard part (33) is sleeved on the butt joint part (32) and is tightly fixed with the butt joint part (32), the main body part (31) is integrally connected with the valve rod (4), and the reverse stopping groove (71) is arranged on the butt joint part (32).

8. The pneumatic globe valve of claim 7, wherein: When the sealing hard part (33) is fixed to the butt joint part (32), the butt joint part (32) is provided with a limiting ring (9) limiting movement of the sealing hard part (33) away from the valve seat.

9. The pneumatic globe valve of claim 8, wherein: The diameter of the limiting ring (9) is smaller than the outer diameter of the sealing hard part (33).

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