METHOD FOR ISOLATING THE INFLOW OF FORMATION WATER IN AN UNCASED HORIZONTAL SECTION OF THE WELLBORE Russian patent published in 2018 - IPC E21B43/32 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry, namely to isolation of water inflows in horizontal sections of wells. Method for isolating a supply of formation water in an uncased horizontal section of an oil wellbore includes the recovery of downhole equipment, carrying out geophysical studies in the open horizontal section of the wellbore, determining the interval of water inflow from the aquifer and descending onto the flexible pipe of the arrangement. Layout consists of a connector, two flap-type check valves, an emergency disconnector, a perforated branch pipe with swell packers 1 m long. At the end of the perforated pipe, a full-length tube with an inner seat is attached by means of a coupling. Initially sealing elements of the swelling packers are left for the time of swelling. Then a ball is dropped from the composite material, whose diameter is equal to the diameter of the full-pass tube. After the ball the waterproofing composition is pumped with the sale of the buffer liquid. Dropped ball enters the saddle of a full-length tube, thereby overlapping its internal space. After this waterproofing composition is pumped into the perforations of the perforated nozzle into the watered interval of the formation. Then ball is dropped into the flexible pipes to the emergency disconnector and hydraulic pressure is applied. Flexible pipe is disconnected from the perforated nozzle and lifted to the day surface. Well is then left for WOC. After that assembly with the mill is lowered into the borehole and work is carried out to drill out the perforated branch pipe, swell packers and waterproofing composition residues with washing them on the day surface. In the end, downhole equipment is lowered, the well is developed and put out on the regime.

EFFECT: proposed invention allows to increase the efficiency of repair and insulation works, to prolong the anhydrous life of the well.

1 cl, 6 dwg