METHOD OF FORMATION OF AXIAL LOAD IN BOTTOM OF HORIZONTAL BOREHOLE AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 1994 - IPC

FIELD: drilling of horizontal boreholes. SUBSTANCE: salient feature of method of formation of axial load in bottom consists in that this load is created with power cylinder with immobile string of drilling pipes. Periodic feed of drilling tools is accomplished by pulses. Device for implementation of method has cylinder with template housing piston 3. Cylinder is coupled with drilling pipes with the aid of spline packing 2. Piston 3 has radial holes 9 for formation of increased pressure above discs 5. Holes 9 may be calibrated or check valves may be installed in them. Cylinder has radial holes to communicate hole clearance with space beneath disc 5. Additional pistons 3 and discs 5 may be mounted in series in cylinder. EFFECT: improved drilling efficiency. 5 cl, 3 dwg