CN1308195A

CN1308195A - Leakproof durable gate valve structure

Info

Publication number: CN1308195A
Application number: CN 01105313
Authority: CN
Inventors: 陈西火
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-02-08
Filing date: 2001-02-08
Publication date: 2001-08-15

Abstract

The structure of said invented gate valve includes valve core and valve seat, and is characterized by that there are at least one-sealing liner bushing made of engineering plastics set in valve core and valve seat, and at least one bulged ring in their contacted place with preferably smooth transition bulged curved surface. The valve core is preferably in the form of downward wedge, and the valve seat possesses a certain retained space in the correspondent low portion. As compared with existent technology, the contact surface between valve core and valve seat with a bulged ring has smaller sealed contacted surface greater action force on the unit area or specific pressure under the condition of the same fluid pressure and thus good effect.

Description

A kind of leakproof durable gate valve structure

The present invention relates to a kind of gate valve structure, particularly a kind of leakproof durable gate valve structure.

At present there is a big chunk to adopt gate valve at pipelines such as industry and civilian water, hot water, water vapor, liquefied petroleum gas, coal gas, diesel oil, gasoline and valve on the equipment, the advantage of gate valve is: fluid resistance is little, has certain regulated fluid performance, applicable to bigbore valve, but gate valve also has its intrinsic shortcoming: processing is comparatively complicated, and since spool be two face seals, its sealing area is bigger than stop valve, thus the sealability relative mistake some.Existing gate valve, particularly being not more than 120 ℃, nominal pressure in medium temperature is not more than in the mesolow gate valve of 2.5MPa, spool and valve seat adopt the hard copper product more, because the sealing surface between spool and the valve seat is " hard-hard " sealing means, therefore sealing surface wearing and tearing or damage easily, in addition, because the variation of medium operating temperature, also cause the local increase of specific pressure easily and cause sealing surface scratch and damage, finally cause sealing effect bad.For this reason, the patent No. is that 90213719.0 " a kind of elastic material is made the gate valve of flashboard lining face " proposed a kind of flashboard (being spool) that is made of the metal frame and the outside elastic material lining face of inside, two sealing surfaces of flashboard are a kind of pipe face that does not have raised step for following wedge shape with the pipe face that flashboard seals mutually.This patent is because of the flexible material of flashboard outer lining, it between flashboard and the pipe face " soft-hard " sealing, therefore sealing effect is better and not easy to wear than " hard-hard " mode, yet this patent simple on making, convenient, valve seat is not set, " is a kind of pipe face that does not have raised step with the pipe face that flashboard seals mutually ", this does not have the support of left and right directions yet with regard to the lower end that means flashboard, and the pressure of tube fluid will all act on the flashboard in use, therefore bigger hydrodynamic pressure will be born in the lower end of flashboard, cause distortion or wearing and tearing easily at this place, and big more just easy deformation or the wearing and tearing more of hydrodynamic pressure on the other hand, will cause that permanent generation leaks and can't remedy in case the sealing surface lower end of flashboard causes wearing and tearing, can only replace flashboard, so the durable leakproof effect is relatively poor.

Purpose of the present invention just is to provide at above-mentioned prior art present situation a kind of leakproof durable gate valve structure of, good sealing effect big at equal tube fluid pressure lower valve core and the specific pressure between the valve seat.

Even another object of the present invention is to provide a kind of sealing surface to have wearing and tearing slightly or deformation also to be difficult for causing the leakproof durable gate valve structure of leakage.

The object of the present invention is achieved like this: leakproof durable gate valve structure comprises spool and valve seat, it is characterized in that having at least a lining that the seal cartridge of being made by engineering plastics is arranged among spool and the valve seat, and both places of being in contact with one another have one to be a convex ring shape at least.

Described bulge loop is good with the convex surface with rounding off.

Described spool is down with side-looking that wedge shape is good, and described valve seat to have certain retaining space with the bottom in correspondence be good.

Compared with prior art, not only seal between spool of the present invention and the valve seat in " soft-hard " mode, and surface of contact between the two is a bulge loop, therefore sealing contact surface is little, under identical hydrodynamic pressure, active force on the unit area is bigger, also be that specific pressure is bigger, good sealing effect, on the other hand, this bulge loop has the convex surface of rounding off, therefore the not fragile or wearing and tearing of sealing surface, in case and sealing surface weares and teares or deformation to some extent, then whole spool moves down under the sealing state, because spool is wedge shape down, therefore and between the valve seat will still keep sealing state and unlikely leakage.

Description of drawings:

Fig. 1 is the structure cross-sectional schematic of the embodiment of the invention one.

Fig. 2 is the structure cross-sectional schematic of embodiment one under opening state shown in Figure 1.

Fig. 3 is the A-A sectional view of Fig. 2.

Fig. 4 is the structure cross-sectional schematic of the embodiment of the invention two.

Fig. 5 is the structure cross-sectional schematic of the embodiment of the invention three.

Fig. 6 is the structure cross-sectional schematic of the embodiment of the invention four.

Embodiment describes in further detail the present invention below in conjunction with accompanying drawing.

As Fig. 1～shown in Figure 3, be embodiments of the invention one, include handwheel 1, gland 2, filler 3, valve gap 4, valve rod 5, spool 6, valve seat 8 and valve body 9, spool 6 is made by metallic material, generally select copper for use, side-looking is wedge shape down, and be with a seal cartridge 7 of making by engineering plastics outward, spool lining 7 both sides sealing faces shown in the figure hollow out can save material, valve seat 8 is a part of valve body 9, it also is metal material, it has a bulge loop 81 with rounding off convex surface in the contacting point with spool lining 7, when spool 6 and valve seat 8 were in sealing state, valve seat 8 still had certain retaining space 82 in the bottom of correspondence, even spool lining 7 weares and teares or deformation to some extent so in use for some time, then when sealing whole spool 6 and lining 7 can move down slightly, thereby and still keep sealing state between the valve seat 8.

As shown in Figure 4, be embodiments of the invention two, be that with embodiment one difference the two ends of valve seat 8 are lined with the seal cartridge of being made by engineering plastics 10, spool 6 does not then have seal cartridge, but with seal cartridge 10 contacting points one bulge loop 61 with rounding off convex surface is being arranged.

As shown in Figure 5, be embodiments of the invention three, be the not only spool 6 outer seal cartridges 7 that are with embodiment one difference, the two ends of valve seat 8 also are lined with the seal cartridge of being made by engineering plastics 10 ', and sealing lining 10 ' has a bulge loop 101 ' with rounding off convex surface in the contacting point with spool lining 7.

For reaching best sealed against leakage effect, the engineering plastics that described seal cartridge adopted should have following characteristics: the heat distortion temperature height, and good heat resistance, at high temperature creep-resistant property is strong, no cold flow, dimensional stability is good; Therefore with adopt the compressive strength height, hardness is big, wear-resisting, aging quality resistance is excellent, acid resistant alkali dielectric corrosion, high-temperature resistant water decomposition, anti-solvent naphtha, outstanding special engineering plastics or the super engineering plastics of mechanical property are the best under high low temperature, as PAI (polyamide-imides), PPS (polyphenylene sulfide), LCP (liquid-crystalline polymer) etc.

At present, these class engineering plastics cost an arm and a leg, therefore be fit to be used for the less seal cartridge of materials being fabricated, but do not get rid of the continuous progress along with science and technology and material industry, the price of these class engineering plastics can reduce greatly, at this moment, also can adopt embodiment four as shown in Figure 6, be that whole valve seat (valve body) or spool or both make by engineering plastics, all the other structures are all identical with embodiment one, do not give unnecessary details.

Claims

1. a leakproof durable gate valve structure comprises spool and valve seat, it is characterized in that having at least a lining that the seal cartridge of being made by engineering plastics is arranged among spool and the valve seat, and both places of being in contact with one another has at least one to be a convex ring shape.

2. leakproof durable gate valve structure as claimed in claim 1 is characterized in that described bulge loop surface is the convex surface of a rounding off.

3. leakproof durable gate valve structure as claimed in claim 1 or 2 it is characterized in that described spool side-looking is wedge shape down, and described valve seat has certain retaining space in the bottom of correspondence.