DEVICE FOR DISCONNECTION OF PIPE STRING Russian patent published in 1998 - IPC

FIELD: oil and gas production industry. SUBSTANCE: this relates to construction and repair of oil and gas wells. Device has upper body and lower body which are telescopically coupled together. Stopper which is located between them is positioned in corresponding seats. Also provided is hollow bush which is adapted for interaction with aforesaid stopper. Stopper is made in the form of spring-loaded piston. Seats for piston are made in the form of coaxial cylinders which correspond to piston. Lower body has passage which connects piston cylinder space with space beyond body. Hollow bush is spring-loaded and positioned on outer surface of upper body. Application of disconnecting device allows at minimal labour and time for cementing tail-pieces of pipes in vertical, inclined, and horizontal bore-holes. This is made possible because inner space of device is free for passing of washing plug without need of using falling ball which closes central passage. Device is simple in design and manufacture. EFFECT: higher efficiency. 1 dwg