DEVICE FOR PERFORATION OF PIPE IN WELL

摘要

FIELD: mining industry. SUBSTANCE: device has body which incorporates hydraulic cylinder with piston made in the form of piercing unit with cylindrical body and head-piece. Device is also provided with at least one sleeve-like piston which is installed in hydraulic cylinder and is made with axial passage in its lower part. Surface of its upper part mates surface of head-piece. Head-piece together with its working body is installed in sleeve-like piston. Sleeve-like piston, cylindrical body and hydraulic cylinder are interconnected with each other telescopically, and they are arranged so that initial axial movement is performed by cylindrical body, then subsequent axial movements to extreme positions are made by sleeve-like pistons. Application of aforesaid embodiment of device allows for making deeper perforations. EFFECT: higher efficiency. 3 cl, 1 dwg