New surface drill rig for Russian gold

“We bought the PowerROC D55 mainly for its high quality but also for its reliability, and that’s very important in this remote region with its low temperatures. In addition, the granodiorite ore in the pit has a compressive strength of 200 MPa so we need a powerful machine to drill it.”

Atlas Copco provided training for the operators and Atlas Copco Service maintains the rig and delivers the parts, although delivery times can sometimes be long due to the remote location.

Working two, 11-hour shifts per day, the PowerROC D55, which is equipped with the DHR6 H56 rotation unit, 114 mm rods and 130 mm spherical button bits, has so far drilled about 20 000 meters.

The benches are five meters high and the holes are drilled on a burden and spacing pattern of 3.5 x 3.5 m. The holes are drilled to a depth of 5 m with 0.5 m of subdrill. A total of 42 holes are drilled per shift and the rig gives an average penetration rate of 0.65–0.8 m/min depending on the rock, or 6.5 minutes per hole.

Emulsion explosives are used and bit grinding takes place after 380 meters of drilling.

The PowerROC D55 is a high capacity drill rig for the hole diameter range of 110–165 mm (4 5/16’’– 6 1/2’’) and is designed for maximum uptime and simplicity of operation. It has an onboard compressor delivering 271.3 l/s of air up to a pressure of 20 bar and strong flushing, helping to ensure straight and clean holes. The straightforward hydraulic design delivers productivity and reliability in demanding applications and the high ground clearance and fast tramming ability provide high maneuverability in tough terrain.

Epiroc operated under the trademark “Atlas Copco” prior to January 1, 2018.