CN102777632A

CN102777632A - Three-way cutoff valve

Info

Publication number: CN102777632A
Application number: CN2011101268521A
Authority: CN
Inventors: 赵阳; 祁魁军; 朱丰元
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-05-09
Filing date: 2011-05-09
Publication date: 2012-11-14

Abstract

The invention discloses a three-way cutoff valve, which is characterized in that a valve stem and a valve clack are driven by a driving mechanism to do an upward and downward linear motion, an upper seal surface of the valve clack is in a contact seal with the seal surface of an upper valve seat to cut off a bypass pipeline, and a main pipeline works normally; and when the valve clack moves downwards, a lower seal surface of the valve clack is in the contact seal with the seal surface of a lower valve seat to cut off the main pipeline, and the bypass pipeline opens. The three-way cutoff valve has the specific structural characteristics that an inner cavity of a valve body is designed to be a sphere, and hollow cavity chambers are added in holes in middle parts of a valve cover and an upper valve seat hub to improve the movement condition of the valve stem. The welding process and welding materials of the upper valve seat, the lower valve seat, and the upper seal surface and the lower seal surface of the valve clack are greatly improved, and thus the hardness of the three-way cutoff valve is greatly increased. By the adoption of the improvement on structure and process, movement characteristics and properties on seal, corrosion resistance and abrasion resistance of the valve are promoted, and the service life of an overall valve is prolonged.

Description

A kind of three-way cut-off valve

Technical field: the present invention relates to a kind of valve mechanism and sealing surface New Process in Making thereof, the application of new material.Being specifically related to is to improve through the valve minor structure, and the sealing surface preparation process is improved and improved the acting characteristic of valve, sealing and valve working life.

Background technique: three-way cut-off valve is the inlet valve of heating power power plant high pressure heating system, and its operating mode is: pressure medium is high, washes away seriously, and switching frequency is high, and requires the valve of switch two-way sealing.This kind valve of domestic production in the past, under the high pressure operating mode, abrasion resistance can be poor; Be easy to generate seal failure, valve open and close jam, the scratch that occurs movement parts in the operating process easily, cause valve to damage and operate malfunctioning; Serious whole deck valve door is scrapped, and the working life of shaping valve is short.

Summary of the invention: technical problem to be solved by this invention is the deficiency that overcomes existing technology, proposes to reduce on the structure friction link of moving element, in the hope of avoiding the generation of jam, scratch phenomenon.Improve the preparation process of sealing pair sealing surface, upgrade sealing surface and form material,, reduce the factor of seal failure, prolong the working life of valve in the hope of improving the sealability of valve.

The present invention solves the problems of the technologies described above through following technological scheme:

1, the inner chamber of valve body adopts the spherical inner chamber structure, and purpose is to reduce the flow resistance of flowing medium in the chamber or the possibility of generation eddy current, reduces the flowage friction heat of high-pressure medium, improves housing and bears pressure status.

2, the friction ring of moving element (valve rod, flap) is reduced few.Valve rod is suitable with the quality of fit adjustment of other contact matching part from top to bottom; Valve rod and valve cover hole, valve rod changed into by the graphite seal with cooperating by original precision-fit of upper valve base hub bore, the cooperation that middle cavity is formed; Valve rod and valve gap have been reduced; Upper valve base complexed metal area of contact, and be full of high-pressure medium all the time, certain to moving up and down of valve rod to a certain extent lubrication in the middle cavity of graphite seal formation; Do not influence valve rod coaxality requirement up and down, increased the relative degrees of freedom of stem movement again.Valve rod and flap adopt sphere turbine cushion block, and are to flexibly connect, and easy automatic centering under the high-pressure medium effect has improved the sealing surface Percent of contact area, and the processing of correlated parts is just easier with it comparatively speaking.Through such improvement, eliminated the jam of valve rod in switching process basically, killed, phenomenon such as scratch, also reduced the switch moment of valve simultaneously slightly.

3, the valve seal pair is manufactured with the sealing surface welding consumables and has been done bigger improvement.Sealing surface of seat up and down, flap upper-lower seal face is made into the melting welding of cobalt tungsten-bast alloy by original Si Taili hard alloy overlay welding; Its material changes the cobalt tungsten-bast alloy into by cobalt-based, and layer is thin and evenly smooth, comparatively saves wlding; And the hardness of cobalt tungsten-bast alloy is high, and wear resistance, marresisttance are good, and shaping only rubs cuts and can reach drawing requirement; Economize the thing saving of work and time, practice thrift cost, most critical be the sealability and the working life of having improved valve.

Description of drawings:

This accompanying drawing only is a kind of signal legend, the main composition part:

1, valve body 2, lower valve base

3, flap 4, flap lid

5, upper valve base 6, sphere turbine cushion block

7, valve rod 8, valve gap

9, seal ring 10, five is opened the shelves ring

11, bolt 12, filler

13, support 14, driving mechanism

The working principle summary:

Driving mechanism (14) actuate valve stem (7) is done straight line motion up and down, and flap (3) together moves with valve rod.Normal working is that medium is extremely exported by inlet, and driving mechanism drives valve rod, flap is up, and bypass is closed in sealing surface and sealing surface of seat contact seal on the flap.When abnormal conditions appearred in system, driving mechanism drove valve rod, flap is descending, flap lower sealing surface and the contact seal of lower valve base sealing surface, and the entrance and exit pathway closure enters the mouth and opens to bypass flow channel, and medium is flowed out by bypass.

The present invention gives full play to technical advantage; Do not increase any part at whole deck valve door; Simplify preparation process, minor structure is improved under the theory of innovation, has realized flexible, laborsaving, the no jam of valve switch, kills, the generation of scratch phenomenon; Improve the sealability of valve, prolonged the whole service life of valve.

Advantage of the present invention and effect: 1, on the basis that does not increase original component, minor structure is improved, and increases the lubricated cavity structure on the stem movement route, has eliminated jam, the scuffing of killing, swipe that valve rod occurs in operating process.2, the innovation of sealing surface hardening process and material improves, and has improved the anti-rotten scrape resistence of valve, wear resistance, has guaranteed the sealability and the working life of valve better.

Specific embodiments: The present invention be directed to the improvement that the existing technology defective is carried out, require to design according to practicability.What it was concrete is: like diagram, and the Lower Half of valve gap (8) mesopore, the centre processes big cavity, and the cavity upper and lower end is respectively put a carbon seal ring, to guarantee retaining medium in the cavity, prevents the metal scraping of valve rod and valve gap hole wall simultaneously.Hub place endoporus is processed in the same way in the upper valve base, forms certain cavity, so that the viscous flow medium is respectively put a carbon seal ring on the cavity, but both closed cavity formed chamber, can play the auxiliary leading role of valve rod again.The improvement that two places are same has been eliminated the jam that valve rod is in operation basically, has been killed, phenomenon such as scratch, has guaranteed the service precision of valve rod.Flap, sealing surface of seat form technology, change vacuum fusion welding cobalt tungsten-bast alloy into by original built-up welding hard cobalt base alloy, are a kind of The application of new technique.In the operating process, welded piece is heated, and is evenly whole; Layer is thin and evenly smooth, smooth, has reduced because of the influence of welding stress to the sealing surface precision, and consumptive material is few simultaneously; Amount of finish is little, and the hardness of what is more important cobalt tungsten-bast alloy is high, and anticorrosive resistance to marring is good; Sealing surface in use is out of shape because of pressure, temperature variation produce sealing, the possibility of inefficacy is little; Improve sealability, prolonged the working life of valve, reached the raising of such valve overall utility ability under working condition.

Claims

1. a two way sealed 3-way high-pressure stop valve comprises driving mechanism, valve body, flap, valve seat, valve rod, valve gap.By drive mechanism, valve gap, valve seat intermediate hole guide-localization are made straight line motion up and down to valve rod, realize the switching of main line and bypass line, and medium does not allow mutual leakage in main line and the bypass line together with flap, and the operation of valve rod must not jam.

2. according to the said valve motion characteristic of claim 1; The valve gap that it is characterized in that the stem movement positioning and guiding has increased plenum chamber in the upper valve base hub intermediate hole, and with graphite seal shutoff; Guaranteed leading role; The certain high-pressure medium of contain again, it is favourable and harmless that valve rod is moved up and down, reduced valve rod jam, kill, scratch takes place.

3 according to claim 1, wherein the valve sealing, life requirements, characterized in that the valve seat sealing surface, the valve sealing surface, vacuum welding to the welding process, welding to the cobalt-cobalt-tungsten-based alloy alloy, the sealing surface hardness, corrosion resistance, Mo performance improved, thereby improving the sealing performance and service life of the valve.