Check valves are automatically actuated. They are opened and sustained in the open position by the force of velocity pressure and closed by the force of gravity. Seating load and resultant tightness is dependent upon back pressure.
Swing check valves are used to prevent reversal of flow in horizontal vertical pipe lines. In vertical lines, advice or any angle from horizontal to vertical, they can be used for upward flow only.
- Class 150 - Cast Carbon Check Valve.
- Class 300 - Cast Carbon Check Valve.
- Class 600 - Cast Carbon Check Valve.
- Class 900 - Cast Carbon Check Valve.
- Class 1500 - Cast Carbon Check Valve.
- Class 2500 - Cast Carbon Check Valve.
- Class 150 valves 1.5" - 30" and class 300 valves-sizes 1.5" - 30" feature an internally mounted hinge pin which eliminate leak path.
- For Class 600 valves, a ring joint bonnet gasket assures positive seal against leakage and accurate alignment of moving parts.
- Seat ring is seal welded to eliminate leak path behind rings.
These valves comply with the applicable requirements of the following standards:
- API 598.
- ABSU B16.34.
- ANSI B16.10.
- ANSI B16.5.
- Standard material is ASTM A216 Grade WCB.
- Standard trim is (13% Cr to hardface) which is suitable for a wide range of applications.