CUMULATIVE PERFORATOR Russian patent published in 2007 - IPC E21B43/117 

FIELD: oil and gas industry, possible use for secondary opening of productive beds in prospecting and extracting oil and gas wells.

SUBSTANCE: cumulative perforator contains body in form of pipe, not subject to destruction form explosion. In the body by means of holding parts cumulative charges are mounted, connected to detonator by detonation cord. In accordance to invention, as charges, detonating elongated charged are used with longitudinal cumulative recess. On external surface of body of perforator longitudinal recesses are made with length lesser than charge length. Longitudinal recesses are positioned along the spiral with 0-180° shift and step either equal to or exceeding the length of charge. Detonating elongated charges are fixedly held in front of recesses at distance from internal surface of pipe equal to focus distance of charge.

EFFECT: increased specific area of opening of casing column.

2 cl, 1 ex