ASSEMBLY FOR MULTI-STAGE HYDRAULIC FRACTURING Russian patent published in 2025 - IPC E21B43/26 E21B33/124 E21B34/10 

FIELD: oil, gas and coke-chemical industry.

SUBSTANCE: invention relates to oil and gas industry and is intended for tight isolation of intervals of oil and gas wells with possibility of injection of solutions and retention of excess pressure in both directions. Layout for hydraulic fracturing in wells with horizontal end comprises a shaft, on which a magnetic metal trap is installed, a lower valve assembly, a lower anchor, centralisers, anti-leakage devices, packers with cup-type self-sealing collars, a circulation valve installed between the packers, an upper anchor, a split nut, an upper valve assembly. Lower anchor is formed from a shoe, grippers with inserts and a cone, the grips are connected to the cone by means of shear screws, the shoe is screwed on the barrel along the thread. Upper anchor is formed from a cone, grippers with inserts and an upper nut. Upper anchor is connected to the barrel through a split nut, which is screwed on the barrel along the thread. Split nut, elastically expanding, is able to jump along the barrel thread under external axial action only in one direction, that is downwards. Anti-flow devices are installed on both sides of the rubber collar and are designed to prevent rubber inflow into the gap between the assembly and the casing string under the action of excess pressure. Lower valve assembly is connected to the barrel from below along the thread and represents a poppet check valve. Upper valve assembly is connected to the barrel from above along the thread and is also a poppet check valve.

EFFECT: improved reliability of the assembly for separation of formations for hydraulic fracturing.

1 cl, 1 dwg, 1 tbl