The butterfly valve is simple in structure, small in size and light in weight, and only consists of a few parts. The valve can be quickly opened and closed only by rotating 90 °. The operation is simple. Together, the valve has outstanding fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the only resistance when the medium flows through the valve body, so the pressure drop through the valve is very small, so it has good flow control characteristics. Butterfly valve has two sealing types: elastic seal and metal seal. For elastic sealing valve, the sealing ring can be embedded on the valve body or attached to the periphery of the butterfly plate. 　

1、 The electric on-off butterfly valve has the line design of the sealing valve to ensure absolute sealing and no air ingress. The plane design of the valve plate seal can ensure that there is no air leakage and other phenomena, and can completely prevent the valve from being stuck due to long-term non use and non opening, so as to ensure good use.