299 / | HD | MINING OR IN SITU DISINTEGRATION OF HARD MATERIAL |
29 | DF | HARD MATERIAL DISINTEGRATING MACHINES {17} |
42 | DF | .~ Sidewall-working (e.g., drum-type cutter) {4} |
53 | DF | .~.~ Vertical cutter tooth orbit {1} |
54 | .~.~.~ Cutter bodily shiftable horizontally |