HORIZONTAL SECTION DRILLING METHOD FOR SCREW-SHAPED OPERATING WELL Russian patent published in 2015 - IPC E21B7/04 E21B43/25 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to the field of oil and gas production. The horizontal section drilling method for screw-shaped operating well includes the following stages: drilling of directional well with horizontal ending, penetrating oil reservoirs of big thickness, which are composed by terrigenous deposits, as well as reservoirs of small thickness while using coil tubing technology that does not disturb the reservoir structure. Drilling of horizontal section for operating well with screw-shaped cycloid profile is carried out by one horizontal shaft. At that drilling of thin layers is made by coil tubing with tubing left as the casing string. Passage of screw-shaped wellbore in the producing reservoir of big thickness is made by drilling of harmonic route with even pitch between complete screw revolution through the full length and right circle in section, while in reservoirs of small thickness the screw profile is made flattened, that is reduced in vertical view and elongated in horizontal view. Well development is carried out by swabbing of the whole well route in sequence from the bottomhole and further by separate intervals discrete in length and time depending on the reservoir structure.

EFFECT: reduced accident rate and maintained collecting properties of the reservoir.

2 dwg