DEVICE FOR PIPE UNSCREWING IN WELL Russian patent published in 2002 - IPC

FIELD: oil and gas producing and mining industries, particularly, devices for unscrewing pipes in well in emergency situations, in well operation and completion. SUBSTANCE: device has a driving shaft with a flushing cavity, anchor with dies and an anchor sealing ring in its lower part. Made on the shaft against locks are radial holes running from the flushing cavity of the shaft to its surface and recesses. Locks with their end surfaces enter the recesses for radial motion. EFFECT: higher reliability, simplified design with extended functional potentialities of device. 4 dwg