Low torque middle cavity pressure retaining gate valve

Abstract

This invention discloses a low-torque, mid-cavity pressure-holding gate valve, relating to the field of valve technology. It includes a valve body, a valve seat, a pin, and sealing gaskets. The valve seat is located within the valve body, with sealing gaskets at both ends of its outer edge. The two ends of the valve seat are sealed to the inner wall of the valve body via these gaskets. A pin hole is provided on the inner wall of the valve body, and a positioning hole is provided on the outer peripheral wall of the valve seat. One end of the pin is interference-fitted with the pin hole, while the other end is clearance-fitted with the positioning hole. In this invention, sealing gaskets are provided on the end faces of the valve seat, and O-rings are provided on the outer edge of the valve seat. When the gate valve is closed and tightened, end face sealing provides double protection. The pin is used to fix the valve seat, preventing axial displacement or significant rotation after insertion. The valve seat is made of stainless steel, creating a certain hardness difference with the brass material of the gate plate. This difference compensates for minor defects during processing when the gate valve is closed and tightened, resulting in a good sealing pair.

Description

Technical Field

[0001] This invention relates to the field of valve technology, and in particular to a low-torque, mid-cavity pressure-holding gate valve. Background Technology

[0002] In common brass gate valves, the sealing material of the sealing pair is the same as that of the valve body, which is leaded brass. There is no independent valve seat; the seat and body are integrated. This consistency in material between the seat and the gate results in no difference in hardness between them, making it difficult to compensate for minor defects during processing and achieving a good sealing effect. Therefore, the processing technology for the sealing pair is extremely demanding.

[0003] Currently, when machining the valve body and gate wedge sealing surface (3° taper on one side) of gate valves, industry manufacturers generally use a fixed clamping method with rotating cutting tools. Due to many factors such as tool rotation and wear of machine tool guideways, the symmetry, taper, and surface finish of the sealing surfaces on both sides are difficult to meet design requirements. As a result, it is difficult to form a "zero-leakage" sealing pair between the valve seat and gate sealing surfaces after assembly. Summary of the Invention

[0004] The purpose of this invention is to provide a low-torque, mid-cavity pressure-holding gate valve to solve the above-mentioned technical problems.

[0005] The technical solution adopted in this invention is as follows:

[0006] A low-torque, mid-cavity pressure-holding gate valve includes a valve body, a valve seat, a pin, and a sealing gasket. The valve seat is disposed within the valve body, and the sealing gasket is provided on the outer edges of both ends of the valve seat. The two ends of the valve seat are sealed to the inner wall of the valve body through the sealing gasket. A pin hole is provided on the inner wall of the valve body, and a positioning hole is provided on the outer peripheral wall of the valve seat. One end of the pin is interference-fitted with the pin hole, and the other end of the pin is clearance-fitted with the positioning hole.

[0007] Preferably, the valve seat also includes O-rings, with the O-rings located between the sealing gasket and the pin.

[0008] Preferably, the valve seat also includes a gate, one end of which is connected to the outer peripheral wall of the valve seat.

[0009] As a further preferred embodiment, the valve body also includes a valve stem, wherein a valve stem seat is provided on the outer wall of the valve body, and one end of the valve stem is disposed in the valve stem seat and connected to the other end of the gate.

[0010] Preferably, the valve body is made of leaded brass.

[0011] Preferably, the sealing gasket is made of polytetrafluoroethylene.

[0012] Preferably, the O-ring is made of nitrile rubber.

[0013] As a further preferred embodiment, the valve seat is made of stainless steel and the gate is made of brass.

[0014] The above technical solution has the following advantages or beneficial effects:

[0015] (1) In this invention, sealing gaskets are provided on the end faces of both ends of the valve seat and O-rings are provided on the outer edge of the valve seat. When the gate valve is closed and tightened, the end faces can be sealed to form double insurance.

[0016] (2) In this invention, the valve seat is fixed by a pin, which can prevent the valve seat from axial displacement or large rotation after it is embedded.

[0017] (3) In this invention, the valve seat material is stainless steel, which forms a certain hardness difference with the brass material of the gate plate. When the gate valve is closed and tightened, it can make up for minor defects in the processing so as to form a good sealing pair. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the low-torque, mid-cavity pressure-holding gate valve in this invention.

[0019] In the diagram: 1. Valve body; 2. Sealing gasket; 3. O-ring; 4. Valve seat; 5. Pin; 6. Gate; 7. Valve stem seat; 8. Valve stem. Detailed Implementation

[0020] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In the description of this invention, it should be noted that terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] Figure 1 This is a schematic diagram of the low-torque, mid-cavity pressure-holding gate valve of the present invention. Please refer to [link / reference]. Figure 1 The diagram illustrates a preferred embodiment of a low-torque, mid-cavity pressure-holding gate valve, comprising a valve body 1, a valve seat 4, a pin 5, and a sealing gasket 2. The valve seat 4 is disposed within the valve body 1, and sealing gaskets 2 are provided on the outer edges of both ends of the valve seat 4. The two ends of the valve seat 4 are sealed to the inner wall of the valve body 1 through the sealing gaskets 2. A hole for the pin 5 is provided on the inner wall of the valve body 1, and a positioning hole is provided on the outer peripheral wall of the valve seat 4. One end of the pin 5 is interference-fitted with the hole for the pin 5, and the other end of the pin 5 is clearance-fitted with the positioning hole. In this embodiment, see [reference needed]. Figure 1 As shown, a sleeve-type valve seat 4 is used. The valve seat 4 is machined and then embedded into the valve body 1. An O-ring 3 is used for axial sealing between the valve seat 4 and the valve body 1, with a sealing gasket 2 at the end. When the gate valve is closed and tightened, it provides end-face sealing, forming a double safety measure. The pin 5 is made of stainless steel. When the valve seat 4 is embedded in the valve body 1, the stainless steel pin 5 fixes the valve seat 4, preventing axial displacement or large-scale rotation. The pin 5 has an interference fit with the valve body 1 and a clearance fit with the valve seat 4, ensuring that the gate 6 and the valve seat 4 sealing surfaces are automatically aligned during mating. Small adjustments to the valve seat 4 ensure a perfect fit between the sealing surfaces of the valve seat 4 and the gate 6, resulting in a good sealing effect. The clearance fit between the pin 5 and the positioning hole on the surface of the valve seat 4 also limits the large-scale rotation of the valve seat 4 when the gate valve is fully open, preventing the gate 6 from falling and hitting the sealing surface when closed, thus protecting the sealing surface of the valve seat 4.

[0024] Furthermore, as a preferred embodiment, it also includes an O-ring 3. O-rings 3 are also provided on the outer edges of both ends of the valve seat 4, and the O-rings 3 are located between the sealing gasket 2 and the pin 5. See [link to documentation]. Figure 1 As shown, the sealing gasket 2 is disposed on the outer edge of the end face at both ends of the valve seat 4 to seal the end face of the valve seat 4. The sealing gasket 2 is used for axial sealing of the valve seat 4.

[0025] Furthermore, as a preferred embodiment, it also includes a gate 6, one end of which is connected to the outer peripheral wall of the valve seat 4.

[0026] Furthermore, as a preferred embodiment, it also includes a valve stem 8. A valve stem 8 seat 7 is provided on the outer wall of the valve body 1, and one end of the valve stem 8 is disposed in the valve stem 8 seat 7 and connected to the other end of the gate 6. In this embodiment, the gate 6 can be controlled by the valve stem 8.

[0027] Furthermore, as a preferred embodiment, the valve body 1 is made of leaded brass.

[0028] Furthermore, as a preferred embodiment, the sealing gasket 2 is made of polytetrafluoroethylene.

[0029] Furthermore, as a preferred embodiment, the O-ring 3 is made of nitrile rubber.

[0030] Furthermore, as a preferred embodiment, the valve seat 4 is made of stainless steel, and the gate 6 is made of brass. In this embodiment, the stainless steel material of the valve seat 4 and the brass material of the gate 6 create a certain hardness difference, which can compensate for minor defects in the manufacturing process when the gate valve is closed tightly, so as to form a good sealing pair.

[0031] In this embodiment, the valve seat 4, treated as a separate component, can function similarly to the gate 6. Both can be machined using a "workpiece rotates, tool does not" method, or even surface grinding, to ensure that the roughness, symmetry, and taper of the sealing surface meet design requirements. This ensures a good sealing effect after assembly, guaranteeing "zero leakage" in the product. The improved sealing performance also reduces the opening and closing torque, ensuring a better user experience.

[0032] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A low-torque, mid-cavity pressure-holding gate valve, characterized in that, The valve includes a valve body, a valve seat, a pin, and a sealing gasket. The valve seat is located within the valve body, and the sealing gasket is located on the outer edges of both ends of the valve seat. The two ends of the valve seat are sealed to the inner wall of the valve body through the sealing gasket. The inner wall of the valve body has a pin hole, and the outer peripheral wall of the valve seat has a positioning hole. One end of the pin is interference-fitted with the pin hole, and the other end of the pin is clearance-fitted with the positioning hole. The valve also includes a gate. Both the valve seat and the gate have wedge-shaped sealing surfaces. One end of the gate is connected to the outer peripheral wall of the valve seat. The pin is interference-fitted with the valve body and clearance-fitted with the valve seat, which can prevent the valve seat from undergoing axial displacement or large-scale rotation and ensure that the sealing surfaces of the gate and the valve seat are automatically aligned during engagement.

2. The low-torque, mid-cavity pressure-holding gate valve as described in claim 1, characterized in that, It also includes O-rings, and the O-rings are provided on the outer edges of both ends of the valve seat, and the O-rings are located between the sealing gasket and the pin.

3. The low-torque, mid-cavity pressure-holding gate valve as described in claim 1, characterized in that, It also includes a valve stem, and a valve stem seat is provided on the outer wall of the valve body. One end of the valve stem is located in the valve stem seat and connected to the other end of the gate.

4. The low-torque, mid-cavity pressure-holding gate valve as described in claim 1, characterized in that, The valve body is made of leaded brass.

5. The low-torque, mid-cavity pressure-holding gate valve as described in claim 1, characterized in that, The sealing gasket is made of polytetrafluoroethylene.

6. The low-torque, mid-cavity pressure-holding gate valve as described in claim 2, characterized in that, The O-ring is made of nitrile rubber.

7. The low-torque, mid-cavity pressure-holding gate valve as described in claim 1, characterized in that, The valve seat is made of stainless steel, and the gate is made of brass.

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