CN210770628U - Regulating valve packing sealing structure - Google Patents

Abstract

The utility model provides a packing sealing structure for a regulating valve. The regulating valve comprises: an upper valve cover, a valve stem and a packing pressure plate; the upper valve cover is provided with a stepped hole, and the stepped hole includes a large hole and a small hole, so The large hole is close to the outer side of the upper valve cover; the valve stem passes through the stepped hole, and the packing pressing plate is used for axially pressing the regulating valve packing sealing structure in the large hole; the The packing and sealing structure of the regulating valve includes: tetrafluoro packing and graphite packing, both of which are placed in the large hole and surround the valve stem, and the tetrafluoro packing is located in the graphite packing away from the side of the upper bonnet cavity. It has the characteristics of anti-leakage and long service life.

Description

Control valve packing seal structure

technical field

The utility model relates to the field of sealing structures for regulating valves, in particular to a packing sealing structure for regulating valves.

Background technique

Patent CN 203147018U "Ultra-low temperature valve stem triple sealing structure", the low temperature valve packing sealing structure introduced, completely failed in actual operation. Because the PCTFE packing directly contacts the low temperature medium, it will cause the PTFE packing to become hard and lose its elasticity. Under the high pressure of the medium, it is easy to leak and lose its effect.

Patent CN 203979388U "A double packing sealing ring group for low temperature regulating valve", the V-type polytetrafluoroethylene introduced also has the above problems.

The patent CN 109827005A "An ultra-low temperature valve fugitive combined packing structure and sealing method", the introduced sealing method contains asbestos ingredients that are prohibited by the state, which belongs to the technical type that is not allowed.

All of the above have the problem of easy leakage.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a packing and sealing structure for a regulating valve, which is used to solve the problem of leakage at the dynamic seal of the valve stem in the prior art.

In order to achieve the above purpose and other related purposes, the present invention provides a packing and sealing structure for a regulating valve. The regulating valve comprises: an upper valve cover, a valve stem and a packing pressure plate, the upper valve cover is provided with a stepped hole, and the stepped The hole includes a large hole and a small hole, the large hole is close to the outer side of the upper valve cover; the valve stem passes through the stepped hole, and the packing pressing plate is used for axially pressing the regulating valve packing sealing structure within said macropore;

The regulating valve packing and sealing structure includes:

tetrafluoro packing and graphite packing The tetrafluoro packing and graphite packing are both placed in the large hole and surround the valve stem, and the tetrafluoro packing is located on the side of the graphite packing away from the inner cavity of the upper valve cover .

Optionally, the tetrafluoro filler is V-shaped in section.

Optionally, the cross section of the graphite filler is rectangular.

Optionally, the regulating valve packing sealing structure further includes a gasket, the chemical property of the gasket is more active than that of graphite, and the gasket is located on the side of the graphite packing close to the inner cavity of the upper valve cover.

Optionally, the gasket is made of zinc material.

Optionally, the regulating valve packing and sealing structure further includes a hard spacer, the inner ring of the hard spacer is in sliding contact with the valve stem, and the hard spacer is located between the graphite packing and the fourth spacer. Between the fluorine packings, and/or the hard spacer is on the side of the graphite packing close to the inner cavity of the upper valve cover.

Optionally, the rigid spacer is rigid plastic.

Optionally, a pressure ring is provided on the side of the packing pressure plate close to the inner cavity of the upper valve cover, the inner side of the pressure ring is in sealing fit with the valve stem, and the outer side of the pressure ring is connected with the orifice of the large hole. Position sealing fit.

Optionally, both the inner side of the pressure ring and the outer side of the pressure ring are sealed by a rubber sealing ring.

Optionally, the regulating valve packing sealing structure further includes a support pad, the support pad is a hard structure, the inner diameter of the support pad is larger than the outer diameter of the valve stem, the graphite packing The support pad is provided on the side close to the inner cavity of the upper valve cover, and/or the support pad is provided between the graphite packing and the tetrafluoro packing, and/or the tetrafluoro packing is far away from all the The support pad is provided on one side of the inner cavity of the upper valve cover.

As mentioned above, the packing and sealing structure of the regulating valve of the present invention has at least the following beneficial effects:

Through the combination design of tetrafluoro packing and graphite packing, and the graphite packing is close to one side of the inner cavity of the upper valve cover, the graphite packing has higher stability, the liquid chemical composition in the inner cavity of the upper valve cover is complex, and the graphite packing has higher High chemical stability, it can ensure sealing and reduce corrosion, protect tetrafluoro packing, so as to have better sealing effect and higher service life.

Description of drawings

FIG. 1 is a schematic diagram showing the packing and sealing structure of the regulating valve of the present invention.

Component number description: upper bonnet 1, valve stem 2, packing pressure plate 3, step hole 11, large hole 111, small hole 112, tetrafluoro packing 4, graphite packing 5, gasket 6, hard spacer 7, pressure ring 8. Rubber sealing ring seal 81, support pad 9.

Detailed ways

The embodiments of the present invention are described below by specific embodiments, and those who are familiar with the technology can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

See Figure 1. It should be noted that the structures, proportions, sizes, etc. shown in the accompanying drawings of this specification are only used to cooperate with the contents disclosed in the specification, so as to be understood and read by those who are familiar with this technology, and are not used to limit the conditions for the implementation of the present invention. , so it does not have technical substantive significance, any modification of the structure, the change of the proportional relationship or the adjustment of the size, without affecting the effect that the present utility model can produce and the purpose that can be achieved, should still fall within the present utility model. The disclosed technical content can cover the scope. At the same time, the terms such as "up", "down", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and clarity, and are not used to limit this specification. The applicable scope of the utility model and the change or adjustment of its relative relationship shall be regarded as the applicable scope of the present utility model without substantially changing the technical content.

The following examples are for illustration only. Combinations can be made between various embodiments, which are not limited to the contents presented in the following single embodiment.

Referring to FIG. 1 , the present invention provides an embodiment of a packing and sealing structure for a regulating valve. The regulating valve includes: an upper valve cover 1 , a valve stem 2 and a packing pressure plate 3 , and the upper valve cover 1 is provided with a stepped hole 11 , the stepped hole 11 includes a large hole 111 and a small hole 112, the large hole 111 is close to the outer side of the upper valve cover 1; the valve stem 2 passes through the stepped hole 11, and the packing pressure plate 3 is used for Axially press the regulating valve packing sealing structure into the large hole 111; the regulating valve packing sealing structure includes: tetrafluoro packing 4, graphite packing 5, optional, the tetrafluoro packing 4 is a section V-shaped. Optionally, the cross section of the graphite filler 5 is rectangular. The tetrafluoro packing 4 and the graphite packing 5 are both placed in the large hole 111 and surround the valve stem 2 , and the tetrafluoro packing 4 is located at a part of the graphite packing 5 away from the inner cavity of the upper valve cover 1 . side. Through the combined design of the tetrafluoro packing 4 and the graphite packing 5, and the graphite packing 5 is close to one side of the inner cavity of the upper valve cover 1, the graphite packing 5 has higher stability, and the liquid chemical composition in the inner cavity of the upper valve cover 1 is complex , the graphite packing 5 has higher chemical stability, which can ensure the sealing while reducing corrosion, protect the tetrafluoro packing 4, and thus have a better sealing effect.

In this embodiment, please refer to FIG. 1 , the regulating valve packing sealing structure further includes a gasket 6 , the chemical property of the gasket 6 is more active than that of graphite, and the gasket 6 is located near the graphite packing 5 . One side of the inner cavity of the valve cover 1. Through the arrangement of the gasket 6, the liquid in the inner cavity of the upper valve cover 1 will corrode the gasket 6 first, so as to achieve the purpose of protecting the graphite packing 5. Optionally, the gasket 6 is made of zinc material.

In this embodiment, please refer to FIG. 1 , the regulating valve packing and sealing structure further includes a hard spacer 7 , and the inner ring of the hard spacer 7 is in sliding contact with the valve stem 2 . 7 is located between the graphite packing 5 and the tetrafluoro packing 4 , and/or the hard spacer 7 is on the side of the graphite packing 5 close to the inner cavity of the upper valve cover 1 . The hard spacer 7 is sleeved on the valve stem 2 and plays a role of guiding the valve stem 2, avoiding or reducing the radial displacement of the valve stem 2 due to external force to deform each packing, resulting in packing leakage. Optionally, the rigid spacer 7 is rigid plastic. The guiding function of the valve stem 2 is ensured, and the valve stem 2 is not scratched during the sliding process.

In this embodiment, please refer to FIG. 1 , a pressure ring 8 is provided on the side of the packing pressure plate 3 close to the inner cavity of the upper valve cover 1 , and the inner side of the pressure ring 8 is sealed with the valve stem 2 . The outer side of the pressure ring 8 is in sealing fit with the orifice position of the large hole 111 . The arrangement of the pressure ring 8 ensures that the packing is axially compressed, and at the same time, it also ensures the isolation and sealing between the packing and the outside world. Optionally, both the inner side of the pressure ring 8 and the outer side of the pressure ring 8 are sealed 81 by a rubber sealing ring. The rubber sealing ring can be an O-ring rubber sealing ring.

In this embodiment, please refer to FIG. 1, the regulating valve packing sealing structure further includes a support pad 9, the support pad 9 is a hard structure, and the inner diameter of the support pad 9 is greater than the The outer diameter of the valve stem 2, the graphite packing 5 is provided with the support pad 9 on the side close to the inner cavity of the upper valve cover 1. The support pad 9 plays a supporting role, and the support pad 9 can be a metal structure. The inner diameter of the support pad 9 is larger than the outer diameter of the valve stem 2, so that the support pad 9 does not contact the valve stem 2 and avoids the support pad 9 to the valve stem. 2 cause scratches. When the support pad 9 is matched with the V-shaped tetrafluoro filler 4 . The cross-section of the support pad 9 can also be designed to be a V-shaped or inverted V-shaped structure corresponding to the cross-section of the tetrafluoro filler 4 that matches the V-shape.

In this embodiment, please refer to FIG. 1 , the support pad 9 is provided between the graphite filler 5 and the tetrafluoro filler 4 .

In this embodiment, please refer to FIG. 1 , a support pad 9 is provided on the side of the tetrafluoro packing 4 away from the inner cavity of the upper valve cover 1 .

To sum up, the utility model is designed by the combination of tetrafluoro packing 4 and graphite packing 5, and the graphite packing 5 is close to the side of the inner cavity of the upper valve cover 1, the graphite packing 5 has higher stability, and the upper valve cover 1 The chemical composition of the liquid in the inner cavity is complex, and the graphite filler 5 has higher chemical stability, which can ensure sealing and reduce corrosion, protect the tetrafluoro filler 4, and thus have a better sealing effect. The combination makes the packing and sealing structure of this scheme have a long life and meet the requirements of the ISO-15848 low leakage standard. Therefore, the utility model effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

The above-mentioned embodiments merely illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims (10)

1. A packing and sealing structure for a regulating valve, the regulating valve comprises: an upper valve cover, a valve stem and a packing pressure plate, the upper valve cover is provided with a stepped hole, and the stepped hole includes a large hole and a small hole, the large The hole is close to the outer side of the upper valve cover; the valve stem passes through the stepped hole, and the packing pressing plate is used for axially pressing the regulating valve packing sealing structure in the large hole; It is characterized in that, the packing and sealing structure of the regulating valve comprises: tetrafluoro packing and graphite packing, both of which are placed in the large hole and surround the valve stem, the tetrafluoro packing is located at a part of the graphite packing far from the inner cavity of the upper valve cover side. 2 . The packing and sealing structure of the regulating valve according to claim 1 , wherein the tetrafluoro packing is V-shaped in section. 3 . 3 . The packing and sealing structure of the regulating valve according to claim 1 , wherein the cross section of the graphite packing is rectangular. 4 . 4 . The packing and sealing structure of the regulating valve according to claim 1 , wherein the packing and sealing structure of the regulating valve further comprises a gasket, the chemical property of the gasket is more active than that of graphite, and the gasket is located in the The graphite packing is close to one side of the inner cavity of the upper valve cover. 5 . The packing and sealing structure of the regulating valve according to claim 4 , wherein the gasket is made of zinc material. 6 . 6 . The regulating valve packing and sealing structure according to claim 1 , wherein the regulating valve packing and sealing structure further comprises a hard spacer, and the inner ring of the hard spacer is in sliding contact with the valve stem, 7 . The hard spacer is located between the graphite filler and the tetrafluoro filler, and/or the hard spacer is on the side of the graphite filler close to the inner cavity of the upper valve cover. 7 . The packing and sealing structure of the regulating valve according to claim 6 , wherein the rigid spacer is made of rigid plastic. 8 . 8 . The packing sealing structure of the regulating valve according to claim 1 , wherein a pressure ring is provided on the side of the packing pressure plate close to the inner cavity of the upper valve cover, and the inner side of the pressure ring is sealed with the valve stem. 9 . The outer side of the pressure ring is in sealing fit with the orifice position of the large hole. 9 . The packing and sealing structure of the regulating valve according to claim 8 , wherein the inner side of the pressure ring and the outer side of the pressure ring are both sealed by a rubber sealing ring. 10 . 10 . The regulating valve packing sealing structure according to claim 1 , wherein the regulating valve packing sealing structure further comprises a supporting pad, the supporting pad is a hard structure, and the supporting pad has a rigid structure. 11 . The inner diameter is larger than the outer diameter of the valve stem, the support pad is provided on the side of the graphite packing close to the inner cavity of the upper valve cover, and/or there is a space between the graphite packing and the tetrafluoro packing The support pad and/or the side of the tetrafluoro packing away from the inner cavity of the upper valve cover is provided with the support pad.

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