Swing Check Valve

Key features/benefits

Check valves are used widely in pipelines conveying liquids, gases and steam. They prevent the fluid from back flow in a very simple manner. The only moving part in the check-valve is the disc with seal, hinged on the body to rotate freely, closing at an angle of 5° .

This design detail ensures the drip tight closing of the disc by gravity even at very low or no-pressure applications. The disc opens in the direction of flow by the inertial effect of the moving fluid automatically. Only at no-flow condition the disc returns to its seat, preventing back flow drip tight. This offers a one-way flow through the valve.

The use of swing type check-valves are very important mostly at the outlet of pumps. It is very important that the disc closes rapidly in pump applications with turn-off or electricity cut-off, before reversing flow slams the disc back to its seat, inducing waterhammer other than induced by the rapid velocity change in the pipeline. Counterweight is added to the check-valve disc stem for that purpose as an optionial feature.