a shut-off valve

Abstract

The invention discloses a stop valve. The stop valve comprises a valve body, a valve deck, a valve rod and a handle; the valve rod is provided with a valve clack; an interception plate is vertically arranged on the terminal end of the valve clack; the interception plate is connected to one end side, close to a medium flow-in channel, of the terminal end of the valve clack; the axial length of the interception plate is smaller than the diameter of the section of the medium flow-in channel which extends in the axial direction of the interception plate; the interception plate is an inversely cone barrel; the round top surface of the inversely cone barrel runs through a round groove in the terminal end of the valve clack; the cone base of the inversely cone barrel is a free end. According to the stop valve provided by the invention, parts are additionally arranged to reduce pressure from a medium to the valve clack in a valve closing process, reduce damage degree of the valve clack due to excessive pressure, enable the valve clack to be connected and sealed with the valve base successfully and improve sealing performance while prolonging the service life of the valve clack; the stop valve has the advantages of simple structure, manufacturing convenience, use reliability and strong practicability.

Description

technical field [0001] The invention relates to a cut-off valve, which belongs to the field of valves. Background technique [0002] Globe valve, also known as cut-off valve, is a forced sealing valve; the opening and closing part of the globe valve is a plug-shaped disc, the sealing surface is flat or sea-cone, and the disc moves linearly along the centerline of the valve seat. The movement form of the valve stem has a lifting and rotating rod type, which can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media. Therefore, this type of shut-off valve is very suitable for cutting or regulating and throttling. Because the opening or closing stroke of the valve stem of this type of valve is relatively short, and it has a very reliable cut-off function, and because the change of the valve seat opening is proportional to the stroke of the valve disc, it is very suitable for regula...

AI Technical Summary

Problems solved by technology

[0003] However, in actual operation and use, when the medium enters the valve from the bottom of the disc, the resistance that the operating force needs to overcome is the friction between the valve stem and packing and the thrust generated by the pressure of the medium, so there is a possibility of closing the valve. The force is different than the force to open the valve, so the diameter of the valve stem is required to be large, otherwise the failure of the valve stem will be bent; moreover, the fluid resistance is large during long-term operation, and the sealing reliability is reduced

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