Check valve

摘要

A check valve for preventing backflow in a conduit. The check valve includes a check valve mechanism having a valve seat defining an opening for fluid flow, a seal retainer positioned downstream of the valve seat and configured to seal the opening and a linkage between the valve seat and seal retainer. The linkage permits guided axial displacement between the valve seat and the seal retainer. The linkage also provides a retention force urging the seal retainer into engagement with the valve seat and creating a fluid seal therebetween when a downstream flow in the opening is insufficient to overcome the retention force provided by the linkage.