Flap valves shall be of the circular port design with offset single pivoted hinge. They shall be of the iron body bronze mounted type and furnished with (flanged end, spigot end, hub end or as called for in the specifications or as indicated on plans). The assembly shall consist of three parts: flap gate, body and hinge pin. The flap gate and body shall be case iron conforming to ASTM specifications
A0126 Class B. The seats and hinge pin shall be furnished of bronze. The flap gate seat ring shall be rolled into a dove-tailed groove under pressure to make one inseparable unit. The body seat ring shall be threaded and screwed into place in the body. Both gate and body seat ring faces shall be machined to a smooth finish. Valves shall be manufactured by Kennedy Valve or approved equal.