METHOD FOR MULTIPLE HYDRAULIC FRACTURING OF FORMATION IN HORIZONTAL BOREHOLE OF WELL Russian patent published in 2019 - IPC E21B43/267 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, namely to methods of wells intensification by formation of cracks in productive formation (hydraulic fracturing of formation – HFF). Method includes construction of horizontal well opening productive formation. Hydromechanical perforator equipped with packer is lowered to the well on the tubing string to the horizontal section of the well. Well casing string and behind-the-casing cement stone are opened by a perforator with isolation of this opening interval with a packer from below upwards several times. Hydraulic fracturing is carried out along annular space of well in series, every time starting from second opening with perforator and installation of packer between opening intervals at pressure not exceeding permissible for casing string and its casing cement stone. Before the hydraulic fracturing, the tubing string is isolated and equipped with a pressure gauge, and during the hydraulic fracturing the pressure in the tubing string is monitored, based on analysis of the maximum pressure value and rate of its increase, presence and intensity of columnar and inter-river flows are determined. Proceeding from geological structure of formation, presence of water-bearing interlayers, etc., and also, processing data on presence and intensity of behind-the-casing flows, decision is taken if necessary to isolate some of them with plugging compound.

EFFECT: disclosed method for multiple hydraulic fracturing of a formation in a horizontal wellbore enables to expand the field of application due to several operations (interval opening, insulation and hydraulic fracturing) in a horizontal formation with monitoring of presence of behind-the casing and inter-formation fluid or liquid flows between intervals of hydraulic fracturing with possibility of making corrections to the processing plan, which allows reducing risks of unplanned watering of products.

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