Single eccentric butterfly valve:
The single eccentric butterfly valve is designed to solve the extrusion problem of the disc and the valve seat in concentric butterfly valves. The structural feature of the single eccentric butterfly valve is that the center of the valve stem deviates from the center of the butterfly plate, so that the upper and lower ends of the butterfly plate is no longer the axis of the rotation, dispersing and reducing the excessive extrusion between the upper and lower ends of the butterfly plate and the valve seat.
Concentric butterfly valve(also called center line butterfly valve):
The structural feature of the concentric butterfly valve is that the center of the valve stem, the center of the valve disc and the center of the valve body are in the same position. Since the butterfly plate and the valve seat are always in a state of extrusion and scraping, the resistance distance is large and the wear is fast. The center line butterfly valve has simple and convenient structure. In order to overcome extrusion and scratching and ensure the sealing performance, the valve seat is basically made of resilient materials such as rubber or PTFE.
According to different end connections, there are concentric wafer type butterfly valve, concentric wafer lugged type butterfly valve and concentric flange type butterfly valve;
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