METHOD AND DEVICE FOR WELL BOTTOM ZONE PERFORATION AND TREATMENT Russian patent published in 2007 - IPC E21B43/18 E21B43/117 

FIELD: enhanced recovery methods for obtaining hydrocarbons by repressuring or vacuum methods.

SUBSTANCE: method involves performing cumulative well perforation and applying implosion action at the end of well perforation within perforation interval with the use of two implosion chambers located from perforator body top and bottom; performing local formation fracturing along with implosion action. To carry out above method perforator body is made of high-strength steel. Additional implosion chamber is arranged under lower implosion chamber. Additional and lower implosion chamber interiors are communicated through channel having diameter less than implosion chamber diameter. Pipe is installed in the channel so that the pipe is directed inside additional implosion chamber. When perforator is brought into operation and implosion chambers are filled with well and formation fluids air present in lower and additional implosion chambers and compressed under the action of inflowing liquid is located between body of additional chamber and pipe so that air dome is created. Compressed air in upper implosion chamber is located in upper part of upper implosion chamber having diameter less than that of implosion chambers so that air dome is created. Diameter and length of upper part in upper implosion chamber and pipe diameter and length are calculated to provide pressure of air compression in upper and lower air domes greater than hydrostatic well pressure, as well as air volume increase to displace liquid columns from interiors of lower and upper implosion chambers one towards another. Pressure pulses created in implosion chambers directed one towards another impinge one upon another inside perforator and create summary pressure pulse directed through perforation orifices in the body to bottomhole formation zone. Implosion chamber volumes are calculated so that time of summary pressure pulse creation concurs with time of liquid column drop in well over vacuum area, which results in summing of pulses from upper and lower implosion chambers with hydraulic impact pulse, and the summary pulse is to be greater than formation pressure. Pulses from upper and lower implosion chambers simultaneously act through perforation channels to create fissured zoned in well bore zone.

EFFECT: provision of local formation fracturing along with perforation operation and implosion action on formation in single trip.

6 cl, 1 dwg