SEAM HYDRO FRAC IN WELL Russian patent published in 2014 - IPC E21B43/267 

FIELD: oil-and-gas industry.

SUBSTANCE: invention can be used for bed hydro frac. Proposed method comprises well wall perforation, lowering of string with packer, landing of packer, determination of total volume of gelated frac fluid, injection of said fluid in under-packer zone, creation in said zone of hydro frac pressure and development of fractures therein and fixation of said fractures by injection carrier fluid with proppant, holding of wells for pressure release, unpacking and removal of packer with string from the well. Note here that flexible string is lowered in pipe string so that bottom end of flexible string is located under pipe string end and at the bed centre. Space between pipe string and flexible string is sealed at wellhead to separate total volume of gelated frac fluid into two equal portions: frac fluid and proppant carrier, to inject in turns both in five cycle and in equal portions. For injection, proppant is used with density lower and higher than that of carrier fluid. In one cycle, fluid carrier and proppant are injected at a time in two equal portions: Carrier fluid with proppant of lower density is injected via pipe string with carrier fluid with proppant of higher density is injected via flexible string.

EFFECT: higher efficiency of hydro frac.

1 dwg