Sandvik Mining and Rock Solutions has introduced a new compact and intelligent single-boom electro-hydraulic drill for tunneling and mining development in narrow-vein drifts.

The Sandvik DD212 is an upgrade of the Sandvik DD210 development drill rig, and is designed for narrow-vein operations. It delivers both high level productivity and low cost of ownership, the mining OEM says.

Based on factory and field tests, the Sandvik DD212 delivers an up to 20% reduction in boom positioning time per face and a circa-15% improvement in drill penetration rate. Its 3% improved pull out ratio, meanwhile, can result in an up to 10 cm greater advance per face when compared with similar equipment.

The machine reached 93% mechanical availability during its mine site test period, accumulating 300 hours of percussion drilling within two-and-a-half months of operation.

“The drill provides great performance with net penetration rate, drill quality and rock tools improvements with zero drill rods jammed during the test period,” Sandvik added.

Among the new features are a drilling control system, the THC562, which provides torque control and reaming hole selection. This enables the DD212 to provide increased drilling performance, while reducing the wear on both the rock drill and rock tools.

The SB20i intelligent boom is used for accurate hole electronic positioning, which enables the precise and fast navigation of drill feed and tool, with automatic parallelism and instrumentation for hole angle measurements, Sandvik says. The boom offers a large face drill coverage from 6-25 m² thanks to the 1 m boom extension and the two narrow-vein type rotation actuators.

The development drill has an extended, 12 ft (3.7 m) TF feed rod, which optimises the advance/round, while its RDX5 rock drill provides a fast drilling cycle time and low operating costs.

The specific compact and versatile CFX telescopic feed, meanwhile, can retract from 12 ft to 6 ft (1.8 m), enhancing multipurpose operation in small tunnel sizes of 2.5 m x 2.5 m to 3.5 m x 3.5 m.

“The DD212 delivers accurate face drilling, cross cutting and bolting and enables mines to open smaller tunnel sections, reducing overbreak, dilution and drilling costs,” Sandvik says.

The company added: “The new DD212 brings operational safety and versatility for tackling different applications, precise electronic positioning, ergonomic operator interface and data monitoring, all leading to a superior pull-out ratio and reduced tool consumption, ensuring that the new DD212 delivers the best fit in narrow-vein drilling.”