Non-contacting mechanical face seal of the gap-type

Abstract

A rotary mechanical face seal for preventing leakage of a fluid, either liquid or gas, across two relatively rotating surfaces. The seal is of the non-contacting mechanical type in which a predetermined spacing is maintained between the relatively rotatable sealing washers by formation of a pressurized fluid film between the relatively rotating surfaces. The opposed faces are constructed to provide a separation of the faces at startup and thereby prevent damage or destruction to the faces before design pressures are achieved. This is achieved by providing at least one of the opposed faces with a deflection bearing portion which causes the necessary deflections under load. The bearing portion comprises a spaced series of lift pad sections. A variety of lift pad constructions can be used. The seal also includes a hydrodynamic radial bearing which centers the shaft in the static state to avoid shaft runout.

Dependencies are inferred from the claim text.