Wafer type butterfly valve is connected to the valve stud in two pipe flanges, its simple structure, small size, light weight, by only a few parts. And just rotate 90 ° to quickly open and close, easy to operate, while the fluid control valve has good features. Valve in the fully open position, the disc thickness is the only medium flows through the resistance of the valve body, through the valve so that the pressure drop generated is small, it has a better flow control characteristics. There are bombs and metal sealing butterfly valve sealing two kinds of seal type. Elastic sealing valves, seals can be mounted on the body or attached to the disc periphery.