Modern Mining July 2016

COVER STORY

Dry drilling puts safety first

Safety is a top priority for Petra Diamonds’ Finsch Diamond Mine in the Northern Cape where a fleet of Sandvik dry drilling support machines has been incorporated to support mining operations at the new Block 5 sub level cave development.

T he kimberlitic ground of the dia- mond mine necessitates dry drill- ing, as water is known to lead to the rapid decomposition of certain kimberlite types which in turn could lead to larger tunnels than originally designed, compromised ground support ele- ments and the pillars between tunnels being insufficient in size. As an additional measure to make mining even safer, the new Sandvik DS411 rock bolters are completely mechanised and controlled by a single operator from un- der a ROPS/FOPS safety cabin or FOPS safety canopy. Saltiel Pule, Sandvik’s business line man- ager UG drills, says in addition to being safe, the bolters are also highly productive and capable of installing between seven to eight rock bolts per hour including welded mesh sheets. This enables production to continue at a rapid and safe pace in line with the require- ments of the mine. Dust suppression “The new rigs also have a number of tricks up the sleeve in order to meet productivity crite- ria as set out by the mine. This includes the machine’s ability to use its short-but-powerful Sandvik RD314 rock drill that is able to deliver

The bolters install between seven to eight rock bolts per hour including welded mesh.

Saltiel Pule, Sandvik’s business line manager UG drills.

the best possible ratio between the rock bolt length and drift height. At the same time the TBR60 boom is able to install varying types and sizes of rock bolts from a single carrier setup,” says Pule. “Unfortunately, with all that speed and power comes the potential for a great deal of dust that could cause health hazards to res- piration as well as safety hazards by blocking visibility around the machines. This meant that a solution needed to be devised in conjunction with dust suppression experts, Ilmeg, to ensure that sufficient suction is achieved at the drilling site to deal with the amount of dust generated. “Finding the right balance to remove the

18  MODERN MINING  July 2016