Seal for rotary shaft in casing has sleeve n shaft with helical grooves to pump leakage fluid back into casing

摘要

The seal for a rotary shaft (50) in a casing has a sleeve (32) surrounding the shaft with a seal ring having rubber sealing lips (22b) in sliding contact with the exterior surface of the sleeve and also plastics sealing lips (23a) also in contact with the sleeve. Helical grooves (32a) are formed in the exterior of the sleeve to exert a return pumping effect on leaking fluid. claims include a method of sealing a shaft using the seal