stop check valve of power station valves

Overview

Purpose

Globe - check valve installed in combined cycle heat on the main steam pipe, prevent the backflow medium, failure occurs when the boiler, quickly close the valve by medium pressure, boiler safety protection effect.

Installation instructions

1.The valve must be vertically mounted on the pipeline,with the stem upward and the medium flowing in under the seat ring.
2.Place the electric actuator in such an environment as non-corrosive non-explosive gas and with the ambient temperature-20~40 degree centigrade and the related humidity 80%.
3.For the electric actuator,when used with the pipeline of a temperature below 350 degree centigrade,use semi-fluid Li-base lubricating oil(Q/SY1002-65) and,when the said temperature is higher than 350 degree centigrade,use GB492-2N-4 sodium-base lubricating grease.

Brief account of structure

1.The valve uses the pressure self-tightened sealing,the higher the pressure,the better the sealing performance,the seal ring uses formed asbestos packing.

2.The disc move up and down inside of the body to first lift the stem before moving and,upon the medium pressure,to let the valve automatically opened.ln case of a failure with the boiler,the valve inlet pressure lowers and the medium flows backward to quickly close the valve.

3.The valve support is connected to the electric actuator to have the valve better sealed.

4.The sealing face between the disc and the seat ring is formed by plasma spray-welding with Co-base carbide alloy,wearable and good anti-scraping performance.
5.The stem surface is anti-corrosive nitration processed,of a good anti-corrosiveness and anti-scraping performance.

6.The valve can be switched in between manual and electric actuation,the power will be automatically cut off in case of the manual actuation and the valve will be closed when turning the handwheel clockwise