METHOD FOR IMPACT INFLUENCE ONTO OIL LAYER Russian patent published in 2004 - IPC

FIELD: oil extracting industry. SUBSTANCE: method includes increasing of liquid column in tubing string lowered in the well until excessive pressure is reached in tubing string and impact chamber limited by casing string and rigid packer, overlapping ring-shaped space between casing pipe and tubing string. Generation of pressure impulses is provided for by sharp periodical lowering and increasing of pressure in force- pumping line, which connects force pump with tubing column, and transfer of pressure impulses from impulse chamber to oil layer. According to the method, a column of liquid in tubing column is formed of at least two layers of liquids of different density. Density of lower liquid layer is taken higher than density of upper liquid layer. Height of liquid layers is determined on basis of condition of maximum excessive pressure taking place in impact chamber during hydraulic impact according to analytic expression. For limiting of impact chamber an additional rigid packer is mounted in bottom-hole of well. Concrete barrel may be used instead of additional packer. EFFECT: increased effectiveness due to increased range of adjustment of impact influence onto oil layer and lowered energy losses in impact chamber. 1 ex, 1 tbl