Komatsu Mining says it has been leveraging technologies to help our customers mine in a more sustainable way, minimising the impact on the environment – Luke Tolley, Product Manager – Hybrid Shovels told IM that one example was demonstrated in a pilot of its 2650CX Hybrid Shovel. The 2650CX pilot unit has operated at Asarco’s Mission copper mine and Climax Molybdenum’s moly mine. Hybrid shovels are designed to deliver the cost benefits of the high productivity of electric rope shovels with the flexible digging and manoeuverability of diesel hydraulic excavators; Tolley said they can fit into operations that run a similar class of hydraulic excavators or rope shovels.

“We are seeing a 40-50% reduction in diesel fuel consumption and greenhouse gas emissions compared to hydraulic excavators. Over its life, the hybrid shovel can save 14,000,000 litres of diesel fuel and 37,000 t of carbon emissions.” SR Hybrid Drive Technology is leveraged on the hybrid shovel to capture regenerative power that is naturally produced. Diesel energy is converted to electrical energy through a switched reluctance generator, which provides power to hoist, crowd, and swing motors. When the 2650CX lowers its bucket or decelerates swing speed, motors become generators, supplying energy to the machine and shutting off fuel supply. Engines do not burn fuel for about 17% of a typical loading cycle, including dig, swing, dump and return swing, contributing to reduced fuel consumption and longer engine life.

“To maximise efficiency, the machine utilises electric power over hydraulic to enable regeneration. The result is 50-60% less hydraulic fluids needed compared to hydraulic excavators. This translates to additional savings through reduced fluid costs, reduced hydraulic routings and fittings, and a reduced environmental impact.” With a payload capacity of 59 t (65 short tons) enabling a four-pass match to 227 t (250 short ton) haul trucks, it will accommodate trucks ranging from 135 to 360 t (150 to 400 short tons).

The P&H 2650CX leverages the hoist and crowd digging forces of P&H electric rope shovels and adds a third force, referred to as breakout force, i.e. bucket curl. Breakout force is key to flexible digging paths, allowing for horizontal digging along the floor, top-down digging, and selective digging — which is a potential requirement in hard rock, multi-seam coal, or banded iron formations. The 2650CX uses a hydraulic clamshell bucket, eliminating the door-latch mechanism commonly found on rope shovels.

Tolley adds: “The capabilities of the 2650CX provide exceptional reach and height, compared to hydraulic excavators. This allows for higher bucket fill factors, increased material excavated between moves, and operation in bench heights up to 16 m. Additionally, efficiency comes from the fixed-boom architecture of the 2650CX. The fixed boom reduces digging mass from hoist motion, requiring less energy during the dig cycle and maximising bail pull throughout the dig profile.”