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clamp butterfly valve is simple in structure, small in volume and light in weight, and consists of only a few parts. The valve can be switched on and off quickly only by rotating 90 degrees. The operation is simple and the valve has good fluid control characteristics. When the butterfly valve is in full open position, the butterfly plate thickness is the only resistance when the medium flows through the valve body, so the pressure drop generated by the valve is very small, so it has better flow control characteristics. Butterfly valve has elastic seal and metal seal. Elastic sealing valve, sealing ring can be inlaid on the body or attached to the butterfly plate.