Prototype trial of mini-drill proves successful at Sigma

The Centre de Recherche Industrielle du Quebec, in co-operation with Atlas Copco, has developed a mini-drill that is innovative in several respects.

Designed to meet the requirements of Sigma mine of Val d’Or, Que., the mini-drill is of reduced size and is constructed of three modules. The unit can be dismantled for easy transport underground and can be readily reassembled.

Once in the mine, reassembly takes about one work-shift, a substantial benefit to narrow-vein mining operation where, for example, drill relocation can occur at least six times per year.

Performance specifications required that the mini-drill be capable of drilling holes 30-45 ft. in length in drifts 2×2 metres (6.6×6.6 ft.). In consideration of underground health and safety, a reduced noise level compared with conventional equipment was also specified.

Features of the new mini-drill include:

— electro-hydraulic drilling with the COP 1032 HB Rock Drill; — double-axial piston pump, pressure-compensated with variable displacement for low-energy consumption and maximum efficiency;

— modular design for fast and easy dismantling;

— flexible feed positioning by means of rotary actuator and slide table. The mini-drill prototype began operation at Sigma, a Placer Dome (TSE) mine, in June, 1990. Its performance in terms of drilling footage has proven to be twice that obtained with conventional pneumatic drills.

In addition, the noise emission level was 10 decibels less than that of the Jackleg-type drill.