METHOD OF MULTILATERAL WELL CONSTRUCTION Russian patent published in 2018 - IPC E21B7/06 

FIELD: oil and gas industry; construction.

SUBSTANCE: invention relates to oil-and-gas industry. Method of constructing a multi-barrel well comprises drilling the main wellbore from the earth's surface to the formation, drilling the rat hole from the previously drilled main wellbore, after completion of its drilling, a casing string is lowered into the rat hole, casing string is equipped in the upper part with a knot to form a multi-barrel "junction" no lower than the third level of complexity according to the TAML classification. Rat hole is drilled from the main wellbore, previously cased by a production string and cemented, opening intervals of unstable deposits prone to precipitation and landslides by the rat hole, and the underlying zone with nonspattering rocks with opening of the reservoir and subsequent complex of geophysical studies. Casing string made of a lower section and at least one upper section is discharged into the rat hole, and lowered in section, while the lower section is equipped with a receiving adapter-disconnector for connection with a subsequent section, and the upper section has a length, determined based on the actual depth of descent of the previous section and the actual interval milled in the "window" string, is of the same or larger diameter and includes at least one casing string, equipped in the lower part with a knot for connection to the previous section located in the well, and the upper one is equipped in the upper part or with a receiving adapter-disconnector for connection with a subsequent section, or with a knot to form a multi-barrel "junction" no lower than the third level of complexity according to the TAML classification.

EFFECT: quality of construction of multi-barreled wells is improved, the risks of defects are minimized during the construction of multi-barrel wells, caused by the lack of a liner.

1 cl, 4 dwg