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Revision Date:
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Updated On: October 22, 2013
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Editorial Change:
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This standard covers only iron-body, bronze-mounted, nonassisted, swing-check valves, 2-24 in. (50-600 mm) NPS, with mechanical-joint or flanged ends that are installed horizontally in water systems. The manufacturer should be consulted for special conditions. Check valve sizes covered by this standard are 2, 2 1/2, 3, 4, 6, 8, 10, 12, 16, 20 and 24 in. (50, 65, 75, 100, 150, 200, 250, 300, 400, 500 and 600 mm) NPS. Sizes refer to the nominal diameter of the waterway through the inlet and outlet connections and the seat ring. 1.1.1 Seating types. Check valves may be of the metal-to-metal seat construction or resilient material-to-metal seat construction. Check-valve body ends shall be flanged or mechanical joint. 1.1.2 Waterway types. Swing-check valves may be of the clear waterway design (where the disc in the full open position swings clear of the waterway) or the full waterway design (where the disc in the full open position is not clear of the waterway but the body is enlarged to provide full waterway area around the disc). In either design, when fully open, the new flow area shall not be less than the area of a circle with a diameter equal to the nominal pipe size. 1.1.3 Pressure ratings. The working water pressure shall be 175 psig (1200 kPa) for check valves with diameters of 2-12 in. (50-300 mm) NPS inclusive. The working water pressure shall be 150 psig (1030 kPa) for check valves 16-24 in. (400-600 mm) NPS inclusive. The working water temperature shall not exceed 125F (52C). 1.1.4 Conditions not covered. The following design and installation conditions are not covered by this standard. 1.1.4.1 Swing-check valves for use in lines conveying water of unusual corrosivity are not covered by this standard. 1.1.4.2 Conditions of water hammer, hydraulic pulsation, and excessive operating noise are beyond the scope of this standard and require special design and construction consideration.
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