SEALING SYSTEM AND BI-DIRECTIONAL THRUST BEARING ARRANGEMENT FOR A DOWNHOLE MOTOR

摘要

A bearing assembly for a downhole motor comprises a housing having an upper end, a lower end, a radially inner surface, and a radially outer surface. In addition, the bearing assembly comprises a mandrel rotatably disposed within the housing. Further, the bearing assembly comprises an upper seal assembly, a lower seal assembly, and a thrust bearing assembly, each radially positioned between the housing and the mandrel. The bearing assembly also comprises a lubricating fluid radially disposed between the housing and the mandrel. The lower end of the housing comprises a first check valve radially positioned between the radially inner surface and the radially outer surface of the housing. The check valve is in fluid communication with the lubricating fluid and is adapted to allow at least a portion of the lubricant to exit the bearing assembly at a predetermined pressure differential.