Swing Check Valve Standard and specification: 1, Design and manufacture: API 6D, BS 1868, ASME B16.35 2, Connection ends: ASME B16.5, ASME B16.47 3, Face to face dimension: ASME B16.10 4, Testing and inspection: API 598, API 6D 5, Normal pressure or rating: class 150 ~ class 900 6, Normal diameter: 2" ~ 30" 7, Major Material:A216-WCB,A105,F304,F316, F11,F22,LF2