METHOD OF LAYER MULTIPLE HYDRAULIC FRACTURING IN INCLINED BOREHOLE Russian patent published in 2016 - IPC E21B43/267 

FIELD: hydraulic engineering.

SUBSTANCE: invention relates to methods of hydraulic fracturing in tilting directional and horizontal boreholes of producing formations wells in incompetent rocks. Method involves drilling of tilting directional borehole through oil-saturated interlayers, lowering of the casing string in the well and cementing of annular space between casing string and rock, perforation of the casing string in the borehole in the range of oil-saturated interlayers, performing multiple hydraulic fracturing (MHF) in the borehole in direction from the bottom to the head by pumping the pipes of fracturing fluid via strings and formation of cracks in oil-saturated interlayers from the borehole and their further fixing by proppant. At that, on the borehole head underarm the pipes string is equipped with a hydraulic jet perforator with self-centering nozzles in the direction of the main maximum stress of the mine rock, and upper - it is equipped with the anchor-centralizer, the pipes string is let down in said inclined shaft to the oil-saturated interlayer nearest to the bottom. Casing string hydraulic jet perforation is performed opposite the oil-saturated interlayer in direction of the main maximum stress of the mine rock, without changing the position of the pipes string, MHF is performed through the hydraulic jet perforator with formation of fracture with its further reinforcement by proppant. If at fracture reinforcement by proppant pressure in the shell side is more than 80 % of pressure value of the processed formation interval closure, then in the shell side a fluid priming with flow rate of 0.2-0.4 m³/min is performed by the pump unit. If the pressure in the shell side is less than 80 % of closure pressure, a fluid priming in the shell side is not performed. Multiple MHFs are repeated depending on the number of oil-saturated interlayers, abdomen by inclined directed borehole. At the end of multiple MHF the pipes string is withdrawn with the hydraulic jet perforator and the anchor-centralizer from the well. Thereafter the proppant is washed out from the inclined borehole.

EFFECT: technical result consists in production efficiency improvement of separate weakly operating oil-saturated interlayers; improvement of method implementation reliability; simplification and reduction of hydraulic fracturing performance duration.

1 cl, 5 dwg