The DTH drilling rig (down-the-hole drilling machine) is a kind of drilling machine, which is mainly used for drilling in rock formations. The down-the-hole drilling rig uses the impactor and the DTH drill bit.
[pdf] Since 2003, HardRock Infrastructure Services has been taking on the kinds of projects others will not touch. What started with one man, one rig, and a pocketful of credit cards quickly evolved into one of the top providers of horizontal directional drilling (HDD) services in the United States.
[pdf] The longer your feed rail, the more important the addition of the energy chain becomes to the overall effectiveness of your machine. We offer a range of feed rail options from 6′ to 24′ for our Skid Steer and E.
[pdf] 
