US Patent 7575413 Abrasion resistant pump thrust bearing

A centrifugal pump has a stationary diffuser with a bore. A thrust bearing has a tubular portion that inserts into the bore. The thrust bearing has an external shoulder that contacts a support surface in the bore of the diffuser for transmitting downward thrust from an upstream impeller to the diffuser. The thrust bearing has an internal shoulder for transmitting upward thrust from a downstream impeller to the diffuser.