According to the structural classification, metal seal butterfly valves can be divided into single eccentric, double eccentric, and three eccentric butterfly valves.
The first eccentricity: the valve shaft is located behind the valve plate shaft, so that the seal can tightly surround the entire valve seat.
The second eccentricity: the center line of the valve shaft deviates from the center line of the pipeline and the valve, which is free from interference from the opening and closing of the valve.
The third eccentricity: the cone axis of the valve seat deviates from the center line of the valve shaft, which can eliminate friction during the closing and opening process and achieve a uniform compression sealing effect around the entire valve seat.
