PROMISING PNEUMATIC PUNCHERS FOR BOREHOLE DRILLING

摘要

The state of borehole drilling by downhole pneumatic punchers and their potential use in open and underground mining as well as in exploration for reliable sampling are analyzed. Performance specification is presented for the new-generation pneumatic punchers equipped with a pin tool, effectively operating at a compressed-air pressure of 0.5...0.7 MPa, and with an additional extended exhaust from the power stroke chamber during working cycle.