Multi-channel deep drilling system has roller bits in two opposed channels in working positions, bit in waiting position in one channel; new bit can be inserted into channel during drilling

摘要

The system has several, especially four, channels (1/1-1/4) symmetrically arranged in a casing (1) and opening into a drilling plate (2). Roller bits (3) are installed in two symmetrically opposing channels in working positions. A bit is arranged in a waiting position in one channel and a new bit can be inserted into a channel without interrupting drilling.