Applicable standards: Design, API 6D / BS 1868 / API 594 Design ISO 14313 Flange Ends, ASME B 16.5 / MSS SP 44 / B16.47 Butt Weld Ends, ASME 16.25 Face to face, ASME B16.10 / BS 2080 Testing, BSEN-12266-1 / API 6D / API 594 Design description: Bolted Cover Swing type, Anti-rotation disc / Wafer type Renewable seat rings / Non renewable seat rings Non-penetrate disc shaft Disc design as per gravitational acceleration. Encapsulated gasket design for effective sealing. Dash Pot arrangement & counter weight arrangement available. Valves for special applications are available like for source service as per NACE MR 0175, Hydrogen service, Oxygen service. Pressure seal Check valves available for pressure class above 900#. Service Application: These unidirectional valves are suitable for moderate velocity services. All installation involves flow and pressure under the disc. Seal welded seats recommended for turbulent flow or thermal cycling. Slamming of check valves can be avoided with suitable arrangements for higher size.