QUICK-RELEASE TIGHT JOINT OF TUBULAR PARTS AND METHOD OF ITS ASSEMBLY-DISASSEMBLY Russian patent published in 2012 - IPC E21B17/04 

FIELD: machine building.

SUBSTANCE: device comprises nipple and coupling with their conical surfaces in contact jointed by sleeve screwed on said coupling. Said conical surfaces allow their guaranteed negative allowance. Ring groove is made on nipple to form flat annular thrust surface perpendicular to joint axis to interact with mating flat thrust surface of extra span of pipe expander drive yoke. In assembly, thrust ledges of nipple and bushing get in contact to allow tightening of conical joint between nipple and coupling, and between coupling and bushing. In disassembly, flat annular thrust surface of nipple interact with mating flat thrust surface of extra span of expander drive yoke to allow unlocking coupling and bushing, hence, tightened conical joint between nipple and coupling.

EFFECT: higher strength and tightness.

2 cl, 4 dwg