Shaft seal for abrasive fluids

摘要

The rotating shaft (12) passes through the housing wall (27) via a bore (22) and is fitted with a sealing ring (42) which rotates with the shaft. The sealing ring has a sealing surface (40) in contact with a sealing surface (38) on a fixed sealing ring (36) attached to the housing. A fixed housing wall (28) covers the two sealing rings and leaves a narrow gap (51). Cleaning fluid is pumped into the space (48) between the fixed housing wall and the sealing rings to flush the seal space. The flushing fluid enters the equipment chamber (16) via the narrow gap to prevent return flow of abrasive material. A sealing lip (50) protects the gap when there is no fluid flow.