The check valve shall be of the double disc, wafer style with torsion spring-induced closure. The valve shall be Wafer style for bolting between ANSI Class 125 flanges. Valves have a Ductile Iron body (ASTM A-536 65-45-12) to fit inside 125# ANSI bolt circles, a two-piece Stainless Steel disc (ASTM type 304), type 304 Stainless Steel dual shafts, ASTM A313, type 316 Stainless Steel torsion spring and have an integrally molded elastomer seat vulcanized to the body. A valve for horizontal flow shall be installed with the shafts in a vertical position. The Double Disc Check Valve shall be Pratt Series 740G as manufactured by the Henry Pratt Company.
Double Disc Wafer Check Valve
The double disc check valve is built with stainless trim to give years of trouble-free operation. The double disc check valve can be installed in either horizontal or vertical pipelines that carry clean water or air. This valve is not intended to carry fluids containing solids such as raw sewage or wastewater. This valve is not suited for fluids that contain hazardous gases. The double disc check valve is designed to provide flow in the direction of the arrow marked on the outside nameplate, and instantaneously close upon sensing flow reversal. The nameplate will also indicate valve size, model number, working pressure, and materials of construction.
