Ductile iron butterfly valve, wafer type with centric disc, one piece shaft supported by bronze radial bearings for smooth operation, rubber lined body. The rubber liner is vulcanized integrally to body and bearings ensuring reduced torque and a long lifetime. This liner extends along the valve faces, eliminating the use of gaskets. The body with centering holes for easy pipe alignment is suitable for mounting between flanges according to DIN PN 10/16 and ASME 150#. Face to face dimensions are according to ISO5752/EN558 basic series 20, API609, DIN3202 K1 and BS5155. For easy mounting of both manual and automatic actuators the valve is executed with a topflange according to the ISO5211 standard. Further applications of series 57 butterfly valves can be found amongst others in general industrial and maritime systems for media such as (ballast) water, gases, hydrocarbons and light corrosive media up to a maximum of 16 bar (PN16 execution). Features: - Connections: Wafer type - Body material: Cast iron, nodular - Valve butterfly material: Bronze - Operation: None