DISCONNECTING DEVICE Russian patent published in 2003 - IPC

FIELD: emergency tools, particularly, disconnecting devices designed for disconnection of free part of pipe string from tool stuck in well. SUBSTANCE: disconnecting device has body connected by means of left-hand thread and safety member to adapter. Unit for breakage of stuck zone includes radial channel for communication of device cavity with annular space and bushing located in body cavity for closing radial channel of breakage zone. Said bushing is movable in axial direction and has bore on external surface, seat for special valve and motion retainer. Body has radial channels. Unit for breakage of stuck zone is made in the form of jetting nozzles installed in body radial channels and milling crown rigidly connected with body and located above nozzles for engagement with their outlet end. Special valve is made of destructible or deformed material. Bushing has stop in the form of spring with supporting member. The latter is locked from axial motion with respect to adapter and spring is installed between supporting member and bushing. EFFECT: higher operating reliability and operating efficiency. 4 cl, 3 dwg