... years professional butterfly Valve manufacture directly suppling:worm gear operated cast iron wafer butterfly valve dn250Flange Drilling ... & Pin: SS410, SS416, SS304, SS316Actuator: Lever,Worm Gear, Pneumatic and Electric ActuatorProduct characters:1. Rubber backed seat with ... installation and maintenance.4. Minimized operating torque. Lever, gear, pneumatic and electric actuators can be chosen.5. ...