DRILLING MACHINE STRINGER FOR BEDROCK DRILLING

摘要

FIELD: mining, particularly drives for drilling with combined rotary and percussive action. ^ SUBSTANCE: stringer comprises elongated cylindrical body having two end parts. The first end part comprises thread for stringer connection with drilling string. The second end part is provided with means to transmit rotation moment to stringer and drilling string. Body has axial flushing channel terminating in outlet orifice at the second part end. The flushing channel is adapted to receive flushing fluid through at least one radial side flushing orifice. Radial outer edge defining side flushing orifice extends along substantially convex line. Bending degree of each end of orifice exceeds that of other parts of said outer edge. ^ EFFECT: decreased damage caused by side flushing orifice configuration. ^ 7 cl, 7 dwg