FIELD: soil or rock drilling; mining.
SUBSTANCE: invention relates to technical means for drilling side holes from the horizontal part of an open-hole, in particular to drilling devices using long-length flexible pipes - coiled tubing. Assembly of the bottom of the drill string (ABDS) for drilling of offshoots from the horizontal part of the open-hole includes serially arranged from the bottom-up up the bit, screw downhole motor (SDM), long flexible pipes (LFP). Additionally, after the bit there is an oscillator-turbulence promoter, after the SDM there arranged is a curve adapter, a telesystem and a connecting unit. Curved adapter is made in the form of a branch pipe of a weighted drill pipe with possibility of threaded connection with an SDM and a telesystem by means of threads with intercepting axes at angle of 2°. Telesystem consists of a housing made from an alloyed drill pipe, in a bottom-up housing there are modules of inclination, gamma-ray logging and pressure gauge of internal pressure, axial load and annular pressure. Between the modules in the body of the telesystem there installed are flexible centralizers made in the form of a ring on the external surface of which there are three spring-loaded lamps from sheet steel. Telesystem housing on the outside at both ends is equipped with centralisers made in the form of rings, on external surface of which corresponding overflow channels are made in the form of longitudinal cylindrical grooves with possibility of working fluid overflow. Outer diameter of centralizers is equal to diameter of bit, telesystem is connected by geophysical cable, which is stored inside LFP column through geophysical tip, with ground equipment. Above the geophysical tip on the inner surface of the body of the telesystem there are notches with the possibility of catching the body of the telesystem. Connecting assembly is made in form of mechanical disconnector, which is a shear pin, destructing at design load.
EFFECT: technical result consists in providing drilling accuracy, monitoring downhole parameters, determining ABDS position in real time, enlarging functional capabilities, increasing drilling speed of offshoot, reducing probability of emergencies in well.
4 cl, 3 dwg, 3 ex
