IMPULSIVE HYDRAULIC FRACTURING METHOD Russian patent published in 2018 - IPC E21B43/26 E21B28/00 

FIELD: mining.

SUBSTANCE: invention relates to mining and can be used to develop and restore the flow rate of production wells, that has decreased as a result of the wall packing of the borehole zone of the asphalt-resin-paraffinic formations and mechanical impurities. Method includes injecting liquid into the well cavity, the formation of pressure drops in the bottom-hole zone in the form of a mass-moving fluid wave moving through the borehole cavity, which is formed during a periodic increase in pressure using a valve that connects the well to a source of liquid under pressure. During hydraulic fracturing, one previously estimates time of a liquid mass movement wave from the mouth to the bottom-hole zone and duration of expansion and closing of formation cracks. Initial pressure is established in the cavity of the well at which the fractures of the reservoir are closed, then the valve is opened for the time during which the wave of movement of the fluid mass reaches the bottomhole zone and acts on the fractures of the reservoir. Then the valve is closed to reduce the pressure in the well to the original value. Hydropneumatic accumulator is connected to the line connecting the valve and the source of pressurized fluid. Additionally, the magnitude of pressure and flow rate of the injected fluid is estimated, the duration of brittle and ductile fracture of the formation rock is calculated and the valve is closed after the onset of the ductile fracture process.

EFFECT: technical result consists in the development of a uniform network of cracks in the near-wellbore zone of the formation.

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