ASSEMBLY FOR DRILLING SIDE BOREHOLES FROM CASED WELLS Russian patent published in 2007 - IPC E21B7/08 

FIELD: engineering of technical means for making additional boreholes in existing inclined wells.

SUBSTANCE: assembly for drilling side boreholes from cased wells, lowered on a column of drilling pipes, contains deflector wedge, connected through sub to stopping anchor, which is made in form of longitudinally corrugated pipe, means for azimuth orientation of wedge inside well borehole, and also means for connecting aforementioned elements to form single device. Invention is special because for influx of working liquid from column of drilling pipes into hollow of stopping anchor pipe assembly is provided with hydraulic duct, which is connected to drilling pipe channel through means for azimuth orientation of deflector wedge, made in form of valve-piston unit, transferring working pressure for stopping anchor inside the well in position of given angular orientation of deflector wedge device, while hydraulic drive by means of telescopic moveable packed connection is engaged with milling device, connected to deflector wedge by means of shear element.

EFFECT: increased reliability and decreased laboriousness during operation.

10 cl, 6 dwg