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] In DTH drilling, the percussion mechanism – commonly called the hammer – is located directly above the drill bit. The drill pipes transmit the necessary feed force and rotation to the hammer and the bit, along with the fluid (air, water or drilling mud) used to actuate the hammer and flush the cuttings. The drill pipes are added to the drill string successively behind the hammer as the hole gets deeper.
[pdf] 
