Abstract
This paper reports results of the wet-head drilling program, with regard to data collection and testing and evaluation of rotary and pneumatic drills. Performance of a noise-abated stopper, although extremely limited in scope, is also presented. Comparisons are made in roof of 40 to 60 shore hardness. Data include drilling rates, bit costs, dust suppression/waste removal, safety, functional limitations, and similar information. It is concluded that wet drilling is faster, quieter, and easier on the operator than stopper drilling, although on the average wet drilling requires more bits than stopper drilling.