BEARING HANGER FOR DOUBLE CORE BARREL Russian patent published in 2002 - IPC

FIELD: drilling of oil and gas wells, particularly, means for coring. SUBSTANCE: bearing hanger includes bearing unit and dump discharge ball valve. Bearing units consists of upper and lower thrust coupling halves interconnected by stem connected with lower coupling half. Radial bearing is located below thrust bearings. Bearing unit has upper sealing unit made in the form of plain bores with packing rings on external surface of stem head. Stem is connected with lower coupling half through bearing unit by means of barrel nut made in the form of piston with flexible washer in upper part, and retainers in lower coupling half, on its external side surface, is plain bore in which flexible washer is installed. Flexible washers are made of antifriction material. Grease is located in internal cavities of bearing unit between stem external surface, internal surface of upper coupling half and end surface of barrel nut. Density of grease is less than that of drilling mud. EFFECT: higher efficiency of coring. 1 dwg