DEVICE FOR PREVENTION OF UNSCREWING AND FALL OF UNDERGROUND EQUIPMENT ONTO WELL BOTTOM Russian patent published in 2003 - IPC

FIELD: oil producing industry, particularly, anchor equipment for fastening of various devices. SUBSTANCE: device has stem with cone connected to underground equipment from below. Located on stem is body with radially extensible slips uniformly spaced over its circumference. External surface of slips upper part has various cut profiles. Slips with transverse cuts alternate either with slips having longitudinal cuts, or with slips with combined cuts. Stem has recess for moving the body over stem with the help of controlled member accommodated in body. Lower part of slips has smooth surface which is in contact with internal surface of production string. EFFECT: higher reliability of device. 10 cl