CN2166284Y

CN2166284Y - Self-tightening seal for valve

Info

Publication number: CN2166284Y
Application number: CN 93237162
Authority: CN
Inventors: 唐国富
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-06-25
Filing date: 1993-06-25
Publication date: 1994-05-25
Anticipated expiration: 2003-06-25

Abstract

The utility model relates to a self-tightening seal for valves. A valve core or a valve base is provided with a dovetail groove and a sealing ring made of rubber materials or rubber plastic materials are inserted into the dovetail groove. The sealing ring is provided with a circular longitudinal section. When pressure is less than 6.4MPa and the valve core is impacted on the valve base, the elastic sealing ring can impact on a sealing surface and can not be extruded to play a thorough sealing role.

Description

Self-tightening seal for valve

The utility model relates to a kind of Sealing of valve.

Valve mechanism on the our times is all based on the compact type sealing technique, for guaranteeing that valve does not leak, must carry out precision machining to spool, valve seat, and after grinding meticulously, applying suitable impacting force again makes spool, valve seat produce resiliently deformable can to make certainly exist on the sealing surface fine uneven up, could form effective seal.If on the sealing surface a little foreign matter is arranged, then very easily produce and leak.In practicality, for the sealing of remaining valid, except that the interior pressure that needs the balance fluid, still needing increases superfluous impacting force, the grinding precision of this impacting force and sealing surface, spool is relevant with degree of agreement, the surface of contact size of valve seat, generally is difficult to be controlled automatically by valve.For this reason, when the design valve, often give and stay bigger surplus, just can guarantee safety operation and sealing reliably, so on human and material resources, expend bigger.

Task of the present utility model is that a kind of valve sealing element that can self-tightening will be provided.

The utility model is to implement like this:

Adopt rubber or other plastic article similar, rubber and plastic composite article to make raw material, be processed into a kind of longitudinal section and be circular annular seal ring to rubber performance.Drive the dovetail groove of a ring-type on the surface of contact of spool or valve seat, the degree of depth of this groove can guarantee that annular seal ring embeds can not come off voluntarily behind this groove and be as the criterion.This Sealing is when valve opening state, and from then on visible this circle is complete on the longitudinal section of seal ring, i.e. this seal ring pressurized not; When valve closing, the circular cross-section of its Sealing is to be pressed in the dovetail groove, and this moment, the Liang Jiaochu of dovetail groove was empty; Firm when crack when valve, the hydrodynamic pressure in the valve will promote seal ring, and this seal ring will be pressed towards one jiao of dovetail groove, and can not be pushed out outside the groove.The area of the longitudinal section of this dovetail groove should be slightly larger than the longitudinal section area of seal ring, generally can be doubly at 1.0-1.15, and preferably greater than 1.1 times of seal ring longitudinal section.When valve is opened in a flash big, seal ring can be pushed to outside the groove by pressure reduction in the fluid, but therefore the inboard of seal ring can form negative pressure and seal ring is inwardly held, and the retardance of adding the inclined-plane of dovetail groove is enough to the thrust of balance fluid, so this seal ring can not be pushed out outside the groove.Through test, seal ring can not take place to be pushed out dovetail groove in pressure reduction≤6.4MPa, considers when enough safety coefficient should be arranged, working pressure can be had made to order to answer≤4MPa is good.

The serviceability temperature of this O-ring seal is relevant with the Manufacturing material of seal ring, and general rubber can normally use in the time of-60 °-200 ℃.This seal ring can be used for as stop valve, gate valve, ball valve, check valve, plunger valve etc., good sealing effect being arranged all on the valve of various models.

Can save the precision machining of parts sealing surface and grinding meticulously after adopting this circular section seal ring, thereby save a large amount of processing charges; Because this lip ring works under resiliently deformable fully, can not influence its working life, generally can open more than 100,000 times and still can keep its sealing function.Even have a small amount of embedding capacitive foreign matter to exist, also can not influence its sealing effect; When working pressure was high more, its impacting force was big more, and sealability is also good more; Because the sealing characteristics coefficient of this Sealing is zero, so spool can be realized sealing to the compressing only need overcome in the fluid and press of valve seat, and valve opening and closing moment substantially constant, open and close briskly, use for a long time needn't be keeped in repair, and is easier to realize automation mechanized operation.The serviceability temperature of this seal ring depends on the material of seal ring.Because this seal ring is applied widely, for the valve of making all-plastic has been created condition.

Below in conjunction with accompanying drawing this self-tightening type valve seal is done detailed elaboration.

Accompanying drawing 1 is that this self-tightening type valve seal is used for the schematic representation that opens and closes on the stop valve;

In conjunction with the accompanying drawings, a kind of self-tightening type valve seal is to drive all dovetail grooves (2) on the sealing surface of spool (1), embedding a longitudinal section in dovetail groove (2) is circular O-ring seal (3), the sealing surface of its valve seat is the plane of general machining, when spool (1) is thrown off with valve seat (4), the cross section of seal ring is rounded, and fluid can freely pass through valve port; When spool (1) to valve seat (4) when compressing, the surface of contact pressurized of seal ring is squeezed in the dovetail groove, seal ring presses the plane of valve seat (4) again simultaneously, thereby reaches the purpose of sealing.Equally, driving all dovetail grooves (2) on valve seat (4), embed the O-ring seal (3) of circular section, is the plane of machining to the sealing surface of spool (1), can play the effect of sealing too.

Claims

1, a kind of self tightening valve seal, constitute by the sealing surface on spool and the valve seat, it is characterized in that this sealing surface is the sealing surface that is compressed corresponding parts by an O-ring seal (3), the longitudinal cross-section of this seal ring (3) is circular, and this seal ring (3) is to embed in the dovetail groove of opening on spool (1) or valve seat (4) (2).

2, according to the self tightening valve seal of claim 1, the area that it is characterized in that the longitudinal cross-section of dovetail groove should be 1.1 times of area of vertical circular section of O-ring seal for best, generally should be in 1.0-1.15 scope doubly.