CN2546694Y

CN2546694Y - Liquid, gas pressure self-balancing stop valve

Info

Publication number: CN2546694Y
Application number: CN02220831U
Authority: CN
Inventors: 周君
Original assignee: Nanjing University of Science and Technology
Current assignee: Nanjing University of Science and Technology
Priority date: 2002-05-29
Filing date: 2002-05-29
Publication date: 2003-04-23
Anticipated expiration: 2012-05-29

Abstract

The utility model discloses a liquid and gas pressure self-balancing stop valve which is composed of a valve body, a valve flap, a valve rod, a valve cap, a sealing ring, etc. The liquid and gas pressure self-equilibrating stop valve is characterized in that the valve flap is divided into an upper valve flap and a lower valve flap; the valve rod is divided into an upper valve rod and a lower valve rod, and the upper valve flap, the lower valve flap and the lower valve brod are arranged in the inner chamber of the valve body. The utility model realizes pressure self-balancing in the starting and stopping overall process of the stop valve. The utility model does not enlarge the valve body of the existing stop valve, and only changes the structure of the inner part of the existing stop valve, and the pressure self-balancing characteristic of the stop valve can be realized. Therefore, the utility model is not only suitable for various penstocks in petrochemical industry, oil field industry, metallurgy industry, thermal power plants, etc., but also specially suitable for big through diameter high temperature and pressure pipelines which can not use the existing stop valve.

Description

Liquid, gas pressure self-balancing stop valve

One, affiliated technical field

The utility model relates to a kind of stop valve, particularly a kind of liquid, gas pressure self-balancing stop valve.

Two, background technique

Ducted stop valves such as petrochemical industry, oil field, metallurgy and thermoelectricity plant mainly are made up of valve body, flap, valve rod and valve gap etc.When this stop valve is closed, because the pressure medium of valve body inlet acts on flap one side, and be directly delivered on the operating valve lever, operate very difficult, its degree is aggravated with the rising of pipeline medium pressure and the increase of valve latus rectum, have a strong impact on the sealability and the operability of valve, also restricted the application of stop valve on high pressure, big latus rectum pipeline.In order to address this problem, Chinese patent application (91220092.8) discloses a kind of stop valve self balancing device.This stop valve is provided with the internal bypass hole on flap, play the pressure release effect during valve opening, but after this stop valve is in closed condition, the pressure medium of valve inlet act on all the time stem packing and on the gasket seal of flange, very easily cause valve leakage out of steam system.How to solve the problem that prior art exists, become the highly difficult scientific research task that needs to be resolved hurrily in the current stop valve technical field.

Three, summary of the invention

The purpose of this utility model is to provide a kind of liquid, gas pressure self-balancing stop valve, its realizes liquid, the pneumatic self-balance characteristic of flap under the condition that is not increasing existing stop valve valve body, make that valve operation is very light, good seal performance, reliable operation and method for making be easy.

The technical solution that realizes the object of the invention is: a kind of liquid, gas pressure self-balancing stop valve, it comprises valve body, flap, valve rod and valve gap, it is characterized in that valve body is provided with sealing surface, flap is divided into flap and lower Disc, valve rod is divided into upper valve rod and lower valve rod, last flap, lower Disc and lower valve rod are arranged in the valve body, lower Disc and lower valve rod are fixedly connected, lower Disc is provided with sealing surface, forming motive sealing by seal ring between last flap and the valve body surface of contact connects, forming motive sealing by seal ring between the pilot hole that lower valve rod passes flap and the pilot hole surface of contact connects, on lower valve rod, also be provided with through hole, make the outlet of valve body connect the chamber communication with valve rod.

Principle of the present utility model is: when stop valve of the present utility model with after pressure piping connects, stop valve is in closed condition, this moment valve body inlet liquid, atmospheric pressure acts on respectively on the inner side surface of flap and lower Disc, since the top end face of last flap by the step surface of lower valve rod stop can not on move, act on the liquid on the flap inner side surface, atmospheric pressure forms thrust upwards to lower valve rod, simultaneously, lower Disc and lower valve rod are fixedly connected, the liquid that is born on the lower Disc inner side surface, atmospheric pressure forms downward thrust to lower valve rod, therefore on lower valve rod, constitute a pair of equal and opposite in direction, direction is opposite and have the self balancing power that increases simultaneously and reduce with the valve body inlet pressure, makes lower valve rod be in pressure self balancing state.When the utility model is in opening process, under the pulling of upper valve rod, lower valve rod moves on beginning together with last flap and lower Disc, displacement distance is also very little, liquid, atmospheric pressure in the valve body inlet are all let out certainly along the annulus that forms between lower Disc sealing surface and valve body sealing surface, the upper side of flap moves on being stopped no longer by the lower end surface of valve gap on this moment, and lower valve rod moves on continuing under the condition that does not have valve body inlet and outlet pressure difference together with lower Disc, until the complete opening valve.When the utility model is in the pass closed procedure, under the promotion of upper valve rod, lower valve rod moves down when the step surface of lower valve rod contacts with the top end face of last flap along the pilot hole of last flap is stable, the liquid of valve body inlet, atmospheric pressure acts on respectively on the inner side surface of flap and lower Disc, on lower valve rod, form a pair of equal and opposite in direction, direction is opposite and have the self balancing power that increases simultaneously and reduce with the valve body inlet pressure, simultaneously, the liquid of valve outlet, atmospheric pressure acts on the lower Disc outer side surface, and be passed to valve rod by set through hole on the lower valve rod and connect on the cross section that the chamber acts on the upper side of flap and lower valve rod, on lower valve rod, form another to equal and opposite in direction, direction is opposite and have the self balancing power that increases simultaneously and reduce with valve outlet pressure, until complete throttle down.

The utility model compared with prior art, its remarkable advantage is: 1, operation is very light, the keying moment of valve only is 1/13～1/40 of existing high-pressure stop valve, manually operated valve series, do not need by any just artificial direct control of force assistance device that adds, mortor operated valve series, required motor power (output) only is 1/tens of existing Electric Actuated Stop Valves, not only the energy can be saved, the cost of Electric actuator can also be reduced simultaneously greatly; 2, the sealability and the working life of valve have been significantly improved, valve action required power is very little, be difficult in the operating process weighing wounded the existing stop valve of valve rod that the sealing surface valve leaks, disposed in being difficult for producing much thin as to alleviate valve rod to the wearing and tearing of stuffing box packing with eliminated in the existing valve common because of the excessive easily external leakage of flange coupling place initiation in valve of steering force; 3, widened the application area of stop valve, the utility model has not only kept whole advantages of existing stop valve technology, also is specially adapted to the big latus rectum high-temperature and pressure pipeline that existing stop valve can't use, but large size replaces existing big latus rectum gate valve; 4, good price performance, the utlity model has good usability, manually operated valve cost and the existing stop valve basically identical produced, existing stop valve of mortor operated valve series or gate valve hang down 20%～30% approximately, interchangeability of parts and versatility have been strengthened simultaneously, for the valve of identical latus rectum, different pressures, can adopt same valve shank diameter, handwheel and filler etc., be more convenient for maintenance and seriation large-scale production.

Four, description of drawings

Accompanying drawing is a kind of structural representation of liquid of the present utility model, gas pressure self-balancing stop valve.

Five, embodiment

Below in conjunction with accompanying drawing the utility model is done progressive the description.

In conjunction with the accompanying drawings, the utility model mainly is made up of valve body 21, last flap 9, lower Disc 3, upper valve rod 13, lower valve rod 15, valve gap 12, seal ring 8 and seal ring 10 etc.Valve body 21 is provided with sealing surface 2, and it is shaped as conical surface, plane or sphere; Lower Disc 3 is arranged in the valve body 21, on lower Disc 3, be provided with sealing surface 1, it is shaped as conical surface, plane or sphere, and constitute sealing pairs with valve body 21 sealing surfaces 2, lower Disc 3 is fixedly connected with lower valve rod 15, lower Disc 3 can move up and down in valve body 21 with lower valve rod 15, forms the unlatching of stop valve or closes; Last flap 9 is arranged on inlet 4 upsides of valve body 21, and connects by seal ring 8 formation motive sealings with valve body 21 inner chambers 7; The pilot hole 19 that lower valve rod 15 passes flap 9 forms the motive sealing connection by seal ring 10, the step surface 16 of lower valve rod 15 contacts with the top end face 18 that is arranged on flap 9, and carry flap 9 and move down, also be provided with through hole 20 on the lower valve rod 15, make valve body 21 outlets 23 that place lower Disc 3 outer side surfaces 22 connect chamber 14 and link up with valve rod; Valve gap 12 is fixedly connected with valve body 21, the lower end surface 17 of valve gap 12 can in the stop valve opening process, limit flap 9 on move; When last flap 9 equate with the excircle dimension of lower Disc 3 or go up that flap 9 inner side surfaces 6 equate with the lifting surface area of lower Disc 3 inner side surfaces 5 and valve closing after on the distance of 17 of lower end surfaces of the upper side 11 of flap 9 and valve gap 12 when generally being not less than 2mm, its using effect the best.

Be example with liquid, the gas pressure self-balancing stop valve of making Φ 100mm now, it is as follows to disclose its main design parameters:

1, upward the external diameter of flap 9 and lower Disc 3 equates that external diameter is Φ 100mm;

2, behind the valve closing, the distance between the upper side 11 of last flap 9 and the lower end surface 17 of valve gap 12 is 2.5mm.

The utility model has been obtained satisfied effect through validation trial.

Claims

1, a kind of liquid, gas pressure self-balancing stop valve, it comprises valve body [21], flap, valve rod and valve gap [12], it is characterized in that flap is divided into flap [9] and lower Disc [3], valve rod is divided into upper valve rod [13] and lower valve rod [15], last flap [9], lower Disc [3] and lower valve rod [15] are arranged in the valve body [21], lower Disc [3] is fixedly connected with lower valve rod [15], forming motive sealing by seal ring [8] between last flap [9] and valve body [21] inner chamber [7] surface of contact connects, forming motive sealing by seal ring [10] between the pilot hole [19] that lower valve rod [15] passes flap [9] and pilot hole [19] surface of contact connects, the step surface [16] of lower valve rod [15] connects with the top end face [18] of last flap [9] is movable, is provided with through hole [20] on lower valve rod [15].

2, liquid according to claim 1, gas pressure self-balancing stop valve is characterized in that upward set through hole [20] of lower valve rod [15], make the outlet [23] of valve body [21] connect chamber [14] communication with valve rod.