Babcock check valvesSWING CHECK VALVES

In swing check valves, the disc swings on a hinge onto the seat to block reverse flow, or off the seat to allow forward flow.

The seat opening cross-section is perpendicular to the centerline between the two ports.

CHARACTERISTICS

Forged of cast carbon, alloy and stainless steel, bolted joint between cap and body, renewable or welded seats.

PRESSURE SEAL BONNET

Swing check valves are available assembled with bolted bonnet or with pressure seal bonnet,  that allows high pressure service. The main feature about the pressure seal bonnet is that the body-bonnet joints seals improves as the internal pressure in the valve increases, compared to other constructions where the increase in internal pressure tends to create leaks in the body-bonnet joint.

Internal pressure forces the bonnet upwards against the gasket, creating forces in the contact areas between the gasket and the bonnet. As pressure increases, leaks probability decreases, because of the tightening of the contact surface between the gasket and the body. The area where the body is in contact with the joint is covered by stainless steel, improving surface’s quality and avoiding corrosion issues.

ASME CLASS