1 min read / March 6, 2024 / Staff writer
After a 12-month trial, the mine operator projected that they could at least double the amount of time between equipment overhauls compared to previous overalls. A similar process has been rolled out to other coal mines in Australia.
Data related to the implementation of the trolley assist system discussed in this case study is provided by a customer of Komatsu, reflect the customer's particular experiences, and are not claimed to represent typical results. Individual results may vary.
Copper Mountain Mine, located in Princeton, Canada, sought the expertise of Komatsu’s Professional Services Team to help improve its haul cycle on several fronts — fuel burn, emission output and speed. The operation used a fleet of Komatsu diesel-electric haul trucks to move minerals. The management team was concerned about managing fuel costs as well as the potential impact of its haul truck gas emissions on air quality and the environment overall.
The highest fuel burn and slowest part of the mine’s haul cycle occurred when its loaded trucks traveled uphill. A long and steep section — a 900-meter portion on its haul cycle route — was especially demanding, resulting in more fuel burn while reducing mine productivity overall. When additional power was needed to drive uphill with a full load, its diesel-electric trucks automatically switched to using the internal combustion engine in order to make the climb. Copper Mountain Mine sought a solution to help minimize its diesel engine use during this long and demanding stretch of road.
SME Equipment, a Komatsu dealer, conducted an in-depth study, and recommended a trolley-assist system for the operation. This add-on to Komatsu diesel-electric haul trucks uses a diesel engine to drive an alternator, which produces energy to power electric wheel motors. When the trolley-assist mode is engaged on diesel-electric haul trucks, the diesel engine and alternator are bypassed entirely. Instead, the haul truck draws energy from overhead lines that leverage the mine’s electrical grid to propel the vehicle.
SME Equipment used key performance indicators (KPIs) to illustrate the benefit of the trolley-assist system. These KPIs included a reduction in fuel volume versus the mine’s traditional usage, overall truck power cost (combined diesel and electricity), and cycle times (converted to an estimated tonnage gain using the truck productivity for that period), while also helping to cut its carbon emissions.
The SME Equipment study compared estimated averages of the mine’s loaded trolley-assist haul cycle metrics versus diesel-only runs, and found that the mine could expect to experience:
These strong estimates convinced mine management to move forward with the trolley-assist system. Komatsu Professional Services developed a solution that used truck locations, beacon arrivals, travel speeds and haul states to determine the best trolley-assist system design and configuration for the mine’s loaded trucks traveling uphill on the targeted section.
A new trolley-assist system was implemented on this long uphill section. SME Equipment outfitted seven of the mine’s Komatsu haul trucks with pantographs and other modifications to take them from a standard electric drive truck to a trolley-capable truck. SME Equipment installed and supported the trolley conversion solution provided by Komatsu.
With the system in place, tracking data for a three-month test period showed that 13,857 loaded trucks ascended the uphill section using only diesel propulsion while 15,363 loaded trucks used the trolley-assist system. This represented 52.6% of the loaded truck fleet using the trolley-assist system when traveling on that steep section.
When the data from newly converted trucks were compared to those that used diesel power, those that used the trolley-assist system helped the mine: