A down-the-hole drill, usually called DTH Drilling Rig, is basically a mini jackhammer screwed on the bottom of a drill string. The speedy hammer activity breaks hard stone into little flakes and dust and can be dismissed evident by the air exhaust in the DTH hammer.
[pdf] This casing string provides initial hole support close to the surface and generally varies in length from about 30 to 300 feet. The casing may be driven or hole drilled. The casing may be cemented if it is nece.
[pdf] The Boyles C5/C5C surface core drilling rig is compact, yet powerful. Its compact design makes it easy to position and transport, even by helicopter. During helicopter transport,. .
The Christensen range of surface core drilling rigs has, over many years, established itself a reputation for reliability and ease of use.. .
For underground core drilling exploration tasks, Epiroc offers the well-established and trusted Diamec range of machines. Diamec rigs are available in a wide variety of forms. The.
[pdf] 
