The down-the-hole drilling rig is an impact rotary drilling rig. Its internal structure is different from that of a general rock drilling machine. Its gad distribution and piston reciprocating mechanism.
[pdf] Cat Rotary Blasthole Drill Rigs offer substantial technology, efficiency and productivity improvements to efficiently reach your mining targeted productivity rates. Learn more about our mining drills here.
[pdf] But here is the silver lining: cheap, affordable geotechnical drilling rigs are plentiful and price with performance. In this buyer's guide, you will learn important considerations in choosing the best geotechnical rigs for small contractors and cost-effective soil testing strategies.
[pdf] 
