ZDLW high temperature welding butterfly valve has the advantages of simple structure, small volume, light weight, only by a few parts. But only can be rotated 90 ° rapid opening and closing, simple operation, the valve has a good flow control characteristics. Butterfly valve in the fully open position, the disc thickness is only when the medium flows through the body resistance, thus generated by the valve pressure drop is small, it has a good flow control characteristics. Butterfly valve with elastic metal seal and the seal two kinds of sealed type. Elastic sealing valves, seals can be mounted on the body or attached to the disc periphery.