DEVICE FOR DRILLING-IN OF WELL CASING Russian patent published in 2010 - IPC E21B43/119 

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to oil-and-gas extraction industry, particularly, to devices intended for secondary drilling-in. Device comprises deflecting appliance with bent channel lowered in casing string on pipes that accommodate hydraulic engine lowered on flexible link, engine output shaft being coupled via flexible shaft with drilling tool furnished with travel limiter. Said deflecting device incorporates anchor element to lock said device relative to casing string in required range. Pipes above deflecting device are furnished with internal stoppers, and the engine is provided with the external limiters interacting in descent with corresponding stoppers to lock the engine relative the pipes to prohibit rotation and descent. Between output and flexible shaft established is an intermediate shaft with a weight, connected with output shaft with an opportunity of the limited axial motion. Link is connected to the hydraulic engine by hollow plug stopped from above by plug with lateral channels located above the self-sealing cuff. Note here that, and the cavity of the plug communicates with hydraulic engine inlet.

EFFECT: possibility to use flexible link to up and down engine with required equipment, reduced costs, higher reliability, ease of operation.

4 cl, 1 dwg