AWWA C703-19 pdf download.Cold-Water Meters—Fire-Service Type
4.1.10 Automatic valves. The valve weights shall be of a copper alloy containing not less than 75 percent copper, such as UNS C89510, C89520, C89833, or C89836, or a similar copper alloy as listed in ASTM B584, or a completely enclosed copper-alloy shell loaded with lead; a stainless steel as listed in ASTM A580; ductile iron as listed in ASTM A536; or cast iron as listed in ASTM A126. The valve and supplemental hinge pins or spindles shall be of a copper alloy containing not less than 75 percent copper as listed in ASTM B584; or of stainless steel as listed in ASTM A580 or ASTM A276; or of monel. Valve and supplemental weight-hinge bearings shall be bushed with hard rubber, as classified in accordance with ASTM D2000; or with bronze in accordance with ASTM B139; or with other suitable bushing material. If the valve contains a clapper, it shall be faced with a removable semihard seat. Valve seats shall be made of a copper alloy containing not less than 75 percent copper, such as UNS C84400 as listed in ASTM B584; or of a suitable engineering plastic, such as acetal in accordance with ASTM D4181, polyphenylene oxide in accordance with ASTM D4349, or polycarbonate (PC) in accordance with ASTM D3935. If the meter has a spring- loaded automatic valve, the valve design shall meet all applicable elements of the above standard requirements.
4.1.11 Bypass check valve. Meters using a bypass system shall be provided with a check valve in the piping downstream of the bypass (low-flow measuring) meter. The check valve interior mechanisms shall be of a copper alloy, such as UNS C89510, C89520, C89833, or C89836, or a similar copper alloy as listed in ASTM B584, or other suitable nonferrous material, such as rubber, as classified in ASTM D2000. The check valve shall effectively prevent reverse flow and shall not bind or stick while in service. The check valve shall be of sufficient size to be used to test either the main line or the bypass meter at the flow rates required by AWWA for the respective meters. If the bypass check valve cannot be used to perform in-line field testing at the required AWWA flow rates, a separate plug shall be provided.AWWA C703-19 pdf download.