HIGH PRESSURE UPSTREAM PUMPING SEAL COMBINATION

摘要

A dual seal combination for sealing the space between a housing (12) and a shaft (10) which passes through the housing (12) is formed of an inboard seal (16) and an outboard seal (18) which are axially spaced from one another to define a buffer zone (20) containing a buffer fluid. The inboard seal (16) has radial faces provided with pumping grooves for sealing high pressure and for pumping buffer fluid from the buffer zone (20) towards the upstream or high pressure side of the seal to lubricate the seal faces and to insure against leakage of fluid.