Petra Diamond’s Finsch Diamond Mine in the Northern Cape has purchased a fleet of Sandvik dry drilling bolters to support mining operations at the new Block 5 sub level cave development.

The machines are being employed to promote additional safety in the kimberlitic ground of the diamond mine which necessitates dry drilling in favour of the usual water-aided equipment. Water is known to lead to the rapid decomposition of certain kimberlite types which in turn could lead to larger support holes than originally designed, compromised ground support elements and eventually support failure leading to the tunnel’s instability.

As an additional measure the new Sandvik’s DS411 rock bolters are completely mechanised and controlled by a single operator from under a FOPS safety canopy. The new section also requires high production outputs and the new bolters are more than capable of keeping pace with the daily progress being capable of installing between seven to eight rock bolts per hour including welded mesh sheets.

Dust suppression
Saltiel Pule, Sandvik’s business line manager UG drills, says new rigs use their short-but-powerful Sandvik RD314 rock drill to deliver 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.

A joint solution between Sandvik and dust suppression experts, Ilmeg, has enabled the usually “dusty” dry drilling of the rock to be conducted under nearly dust-free conditions which not only contributes to better visibility and respiratory safety, but also creates a cleaner and more sanitised environment for miners to operate in.

“Finding the right balance to remove the dust from the drilling site required some careful engineering with meticulous record keeping and hundreds of different settings due to the sheer amount of dust generated, but the end result has been a great success and the mine’s four rigs are able to operate in a safe and near-dust-free environment with full time technicians on site at all times to manage dust suppression systems,” says Pule.

Experienced operators
He continues that Sandvik has a longstanding relationship with Finsch Diamond Mine and the mine enjoys a full maintenance contract with approximately 117 full-time service personnel and other staff employed on the mine. This arrangement makes it more feasible to deploy new technology on site, as the OEM has the ability to monitor and apply best practices from around the world in order to optimise equipment and operations on site. 

“Also, as a key partner to Finsch Diamond Mine it has been particularly heartening to know that the solution we have supplied is easily able to keep up with production requirements, while simultaneously ensuring a safer underground environment for all miners concerned.”

He concludes that the success of the Finsch Diamond Mine project is based on working together with the customer to understand their challenges and achieve results based on their output requirements, while maintaining the principles of environment, health and safety.”