CASING WINDOW CUTTING SYSTEM (VARIANTS) Russian patent published in 2023 - IPC E21B29/06 

FIELD: drilling and oil industry.

SUBSTANCE: group of inventions relates to devices for milling a window in a casing string. The system according to the first version includes a whipstock with a guiding surface, an anchor attached to the lower end of the whipstock, and a milling tool. The milling tool consists of a window milling cutter and an upper milling reamer located higher along the wellbore relative to the window milling cutter, having a section of the body with a thickening before the start of cutting, two cutting sections of different diameters, the largest of which is ground. The whipstock has a diamond-shaped surface hardening, the anchor is mechanical and contains a retractable die made with pyramidal notches over the entire area of the die, a retaining ring, a set screw and anchor extraction screws.

EFFECT: premature wear of the window mill cutting sections is reduced, its service life is increased, the probability of mechanical wear of the cutting sections and the body of the milling reamer and premature activation of the hydraulic anchor during the descent process is reduced.

6 cl, 7 dwg