METHOD AND DEVICE FOR DEEP DRILL WELL PERFORATION Russian patent published in 2007 - IPC E21B43/11 

FIELD: oil and gas production, particularly perforators and permeators.

SUBSTANCE: method involves lowering perforation device provided with flexible shaft and cutting tool into predetermined well interval; pressing the device to well wall and fixing thereof; transmitting rotation to flexible shaft and slowing flexible shaft movement during limited axial movement thereof; increasing longitudinal rigidity of flexible shaft; increasing radius of flexible shaft curvature; performing perforation in working regimes of axial advance and stable rotation of slowed shaft. Device comprises body with shaped longitudinal slot and radial channel having turning. Telescopic flexible diverter is located in the shaped slot. Flexible shaft with cutting tool is arranged in radial channel. Stepped conductor is fixed in device body. Device also has pressing and fixing unit, which pressed device to well wall and retains the device inside well. Flexible shaft slowing unit has brake blocks including one sliding one and comprises drive, which presses brake blocks to outer surface of flexible shaft.

EFFECT: increased efficiency.

13 cl, 2 dwg