METHOD FOR OBTAINMENT COMPOSITE CUMULATIVE JETS IN PERFORATOR CHARGES Russian patent published in 2015 - IPC E21B43/117 

FIELD: oil and gas industry.

SUBSTANCE: method for obtainment composite cumulative jets in perforator charges includes initiation of explosive charge with open cavity shaped as a spherical segment in explosive charge body towards cavity, liner of the cavity by different materials. Each next layer following the previous layer joining the cavity of explosive charge is made of material with less specific weight in regard to the same value of the previous layer material; tossing explosion products to the liner, reversing the liner along the charge symmetry axis towards opposite side of its movement, breakaway of inner layer of the liner from outer one, forming composite cumulative jet from inner layer of the liner with maximum speed, which is bigger than maximum speed of the formed cumulative jet from outer layer of the liner. The liner is made layered with at least two layers; all layers are made separate and of different thickness with reduction of the layer thickness from the central part towards peripheral part and from the butt end of charge with depression an axisymmetric hollow converter is placed and its inner profile is shaped mainly as truncated cone narrowing towards direction of cumulative jets movement. In process of tossing and reversing of cumulative liner peripheral part of the liner is impacted additionally in sequence, at first to the liner of material with less density, then to material with bigger density due to their mutual collision and sliding along inner surface of the converter thus converting longitudinal velocity of the liner tossing to radial speed of its compression.

EFFECT: increased depth of perforation channel.

2 dwg