METHOD OF CONSTRUCTION OF MULTI-BOTTOM WELL AND MOUNTING DEVICE THEREFOR Russian patent published in 2018 - IPC E21B7/08 E21B43/10 

FIELD: drilling of soil or rock.

SUBSTANCE: group of inventions relates to the field of drilling, fixing and repair of oil and gas wells. Method of construction of a multilateral well includes drilling the main bore, lowering the casing of the main borehole, equipped with a device for attaching an additional bore, containing a sleeve with a connecting pipe, pressed into the sleeve, cementing the casing, outputting the connecting pipe in the installation interval, mechanical expansion of the device, drilling through it an additional shaft with its fastening, before running the casing in the installation interval of the sleeve the expansion of the main barrel is carried out to ensure the deviation of the connecting pipe sleeve to the desired angle. During the descent, a sleeve is inserted into the casing for placement in the installation interval, with a connecting pipe plugged at the end, below which an emphasis is placed to install and orient the corresponding deflector wedge, outputting and straightening up to the mechanical expansion of the connecting pipe is carried out by overpressure in the casing string after cementing until the cement mortar is cured. Deflector wedge is lowered into the casing until it interacts with an appropriate stop with orientation relative to the connecting pipe for its subsequent mechanical expansion, drilling of the plugged end and drilling an additional barrel with fastening this stem with a shank.

EFFECT: simplified construction of multilateral wells and reduction of time, labor and material costs, expansion of technological capabilities.

3 cl, 4 dwg