WELL PERFORATOR Russian patent published in 2002 - IPC

FIELD: oil producing industry, particularly, well drilling; applicable in perforation of casing strings. SUBSTANCE: perforator has body made in the form of wedge with recesses, cylinder with piston and cutting tool in the form of cutters installed in recesses for motion. Body top is connected with rope. Cylinder and piston are arranged in body so that cylinder underpiston part is communicated with internal cavity if well. Check valve is installed in cylinder upper part. Cylinder is filled with fluid and forms high-pressure chamber. Low-pressure chamber is located above cylinder. Installed between chambers is dynamic spring-loaded valve with internal through channel. In operating position, dynamic valve closes check valve. Support is connected to piston through rod. Support lower part has radial recesses. Cutters are installed into said recesses for motion. EFFECT: simplified design and extended potentialities, reduced material expenditures for round-trip operations. 2 cl, 2 dwg