The valve is widely used at cold air pipe of blast furnace system in building material, metallurgy, oil, electric power industries etc. It can reduce or stop transmitting air to furnace without stopping fan and emit the otiose gas to the atmosphere through the pipe..
The valve is made up of body, disc, pole and discharging air cylinder etc. Manual valve realizes the open-close of gate by making the lever turning the butterfly disc. Electric valve realizes long- range control of open-close of gate to emit gas by making the electric device driving the butterfly disc.