PERFORATOR Russian patent published in 1994 - IPC

FIELD: oil industry. SUBSTANCE: perforator has a hollow case provided with side guide nozzles and bottom. A centering unit, which is made of extensible pistons, is positioned on the case. A charge of solid fuel is received within the case. The case is sectional. The charge of solid fuel is received in each section. The bottoms of the sections are provided with cylindrical projections and form ring spaces together with the case. The bottoms are provided with through openings and provide serial operation of the sections when the perforator is in the operation position. Valves overlaps the through openings. The charges provided from the side of faces allow fluid to flow freely through side guide nozzles. Sides of the charges have two-layer covering having flexible outer layer. The flexible layer is fitted on the cylindrical projections with interference. The expansible pistons are received in the bottoms for hydraulic communication of above-piston spaces with the section spaces through the ring spaces. The section spaces are hydraulically coupled with ambient through the side guide nozzles. EFFECT: enhanced efficiency. 2 dwg