Stop cock and associated sealing rings

摘要

A stop cock has a flow channel controlled by an axially moving piston. In the closed position the piston enters a first sealing ring (2) comprising radially aligned lamellae (20) of a soft material, pref. expanded graphite, interleaved with metal, lamellae (21). A second sealing ring prevents water leakage between the piston and the housing.The sealing ring construction includes a deformation of the metal lamellae (21) close to the flow surface (22) and in the axial direction. Deformation leaves a max. thickness (a) of each soft lamellae (20) free for radial movement. The second sealing ring has a similar design, but has a PTFE ring on each axial end face.