METHOD OF MULTIPLE HYDRAULIC FRACTURING OF FORMATION IN OPEN INCLINED WELL HOLE Russian patent published in 2018 - IPC E21B43/267 E21B43/27 E21B43/114 

FIELD: mining.

SUBSTANCE: invention relates to methods of hydraulic fracturing in open boreholes of horizontal wells that have opened up a multi-layer productive oil reservoir with low filtration-capacity properties with plantar water in carbonate rocks. Method includes drilling a well in a productive formation, determining the reservoir properties and identifying reservoir intervals with low reservoir rock properties, running the tubing string into the well, performing interval HF in an open wellbore by forming perforations and cracks by injecting a gelled fracturing fluid. At the mouth of the well, the following arrangement is set up from the bottom of the pipe string: a plug, a jet nozzle with nozzles, a bypass valve, a shank, a process packer; run the pipe string with the arrangement into the inclined wellbore so that the nozzles of the jetting nozzle are located opposite the interval with low filtration and capacitive properties corresponding to the upper productive formation, carry out HF in this interval, fracturing is generated by pumping a gelled liquid, which is used as the gelled acid, and fixing the fracture with proppant, at the end of the HF, move pipe string to the next interval with low filtration-capacitive properties corresponding to the underlying productive formation, and carry out HF with fracture formation and proppant crack attachment, likewise moving the pipe string with the arrangement to the bottom of the well, perform HF in the remaining intervals with low filtration-capacitive properties in the corresponding lower-lying productive formations, and with each subsequent execution of the interval HF, the length of the formed fracture is reduced by reducing the volumes of injected gelled acid and the concentration of proppant to fix the formed fracture in each interval of the HF, and a 40/70 mesh proppant is used, after the completion of the HF, a ball is dropped into the tubing string, the pressure in the tubing string is sufficient to break the shear bolt of the bypass valve, while the relief valve sleeve moves downwardly and seals the nozzles of the jetting nozzle from the inside, plant the technological packer in the cased part of the well and develop the well with a decrease in the liquid level to 1,000 m, with the pumping of liquid from the borehole into the chute tank in a volume of 25 m³, with sampling at pH, if the pH value is less than 4, continue pumping to a pH of more than 4, with sampling every 10 m³ of the evacuated liquid, after which the development of the well is stopped, the process packer is unpacked and the tubing string is removed with the assembly from the well.

EFFECT: technical result is increased efficiency of the method in a multi-layer reservoir with plantar water.

1 cl, 3 dwg