AWWA C 520:2014

This standard describes bonneted, bonnetless and one- and two-piece fabricated stainless-steel and cast ductile-iron body knife gate valves with resilient or metal seats, including tapping knife gate valves, for use in water, wastewater, and reclaimed water systems with pH range from 6 to 12 and a temperature range from 33ºF to 125ºF (0.6ºC to 52ºC). The minimum design pressure shall be 150 psig (1,034 kPa) for nominal sizes 2 in. to 24 in. (50 mm-600 mm), and the minimum design pressure for nominal sizes 30 in. to 96 in. minimum (750 mm-2,400 mm) shall be 25 psig (172 kPa), 75 psig (517 kPa), and 150 psig (1,034 kPa).