A Bucyrus 49HR rotary blasthole drill equipped with a 107 m3/min air compressor has ben commissioned at Collahuasi copper mine in Chile. This is the first of two 49HR drills equipped with high altitude air compressors that Collahuasi will receive in 2009. Collahuasi is situated in Northern Chile at an elevation of 4,500 m – an ideal environment for use of a 107 m3/min air compressor. This combination should maximise drill productivity at Collahuasi by enabling drill operators to achieve target bailing velocity and optimum radial clearance.
Air compressors de-rate in high elevation and high temperature environments, causing bailing velocity to decrease. As bailing velocity deteriorates, so too will drill productivity. The use of a 107 m3/min air compressor at an operating pressure of 448 kPa, like the option available for Bucyrus drills, allows drill operators to maintain target bailing velocity – between 2,240 and 3,660 m/min) – and optimum radial clearance – 25.4 to 50.8 mm) – in both high elevation and high temperature environments. Bucyrus drills equipped with 107 m3/min air compressors are also beneficial in mines with fractured rock strata, as air released from the compressor can escape into ground cracks, causing loss of air volume. The added power offered by this air compressor will reduce the net loss of air volume in porous ground, ensuring target bailing velocity and optimum radial clearance.
In addition to the productivity benefits offered, the Bucyrus 49HR Drill equipped with such a compressor garners greater energy savings for mine owners/operators. Because the Bucyrus 107 m3/min air compressor option has an operating pressure of 448 kPa, as opposed to 758 kPa, the drill is able to operate at lower power. In fact, when compared to a drill equipped with a 107 m3/min compressor using an operating pressure of 758 kPa), the drill and compressor combination at Collahausi should require nearly 150 kW less to meet equivalent drilling productivity. Thus, operating at a lower power will lower associated energy consumption and cost while maintaining an equivalent rate of productivity.
The Bucyrus line of rotary blasthole drills equipped with a 107 m3/min air compressor offer the a good drilling solution for high elevation (above 2,440 m), high temperature (above 38oC), and heavily fractured ground strata mine environments.