What are swing check valves?

Swing check valves have a disc which swings into position, and can operate in either horizontal or vertical (upward flow) positions. Movement through the line automatically swings the disc open to allow full flow, so swing check valves must be installed with normal flow opening the disc.

Should reverse flow occur, the reversed pressure and the weight of the disc closes the disc back against the seat and back-flow is stopped immediately.

This type of check valve offers minimal flow restriction allowing full flow to be achieved through the valve.