However, the trip from bench face to mill is, for ore, sometimes only half the haulage journey. The thousands of tons of concentrate produced by a large process-ing plant often have to be transported sig-nificant distances to a shipping point. Depending on available infrastructure, that trip can be measured in hundreds of meters—or in hundreds of kilometers— and it’s usually handled by truck types that aren’t as familiar to the mining com-munity. For mines to extract the full meas-ure of operational efficiency that they strive for, the anonymous trucks that carry out this back-end segment of the haulage chain must be as efficient and reliable as their pit-bound fleet mates.
Recently, examples of how two mines that are somewhat geographically adjacent handle this haulage requirement on very different routes came to E&MJ’s attention.
The Long Run
Scania’s Swedish subsidiary has entered into a long-term agreement, commencing in late 2012 and extending to 2021, for over-the-road transportation of iron ore concentrate from Northland Resources’ mining operation near Kaunisvaara in far northern Sweden. The order, valued at SEK 1.5 billion, calls for Scania to deliver a large fleet of truck-and-trailer combina-tions and service-related products tailored to the client’s strict demands pertaining to load capacity, uptime and delivery preci-sion. The order was placed by the mining company’s general contractor, Swerock, which is a subsidiary of Swedish construc-tion and civil engineering company Peab.
The Scania model R730 trucks will per-form round-the-clock service with annual driving distances of 400,000 km for haulage of the concentrates to a railway depot for reloading to trains. The rigs, said Scania, are optimized for gross weights of up to 90 mt. When the mining operations are fully developed by 2015, some 80 trucks and 400 drivers will be responsible for ensuring road transport of the almost 5 million mt of iron ore concentrate.
Scania’s overall effort for Swerock cov-ers delivery of truck combinations with specially built trailers, driver training and coaching, vehicle monitoring, maintenance and repairs of trucks and trailers, including tires, supplies and service. “This is the most comprehensive deal we have con-cluded to date with the Swedish mining industry. We have used the overall compe-tency of the Scania organization to cater for the various parameters, which aside from the trucks and trailers themselves, are crucial for our customers’ profitability. For instance, Scania has also been involved in planning the transportation arrangements and road transport infrastructure,” said Sandro Grimpe, service marketing director at Scania-Bilar Sverige AB.
Scania said it will endeavor to meet the mining company’s requirement for seeking continual reductions in the cost per ton transported over a nine-year period based on performance indicators for expenditures on fuel, tires, repairs and maintenance.
To ensure vehicle uptime, Scania’s SkellefteåBil AB dealership in northern Sweden will expand operations at its serv-ice workshop in Kiruna. In the future, it may be necessary to establish a service business in the Kaunisvaara area (near Pajala) as well.
Another element in Scania’s effort is that both trailers and the ‘dolly’ used to connect the truck and trailer will be equipped with axles made by Scania. “This means that our workshops can maintain just as high [a level of] service competency and accessibility to parts for trailer axles as for Scania’s own vehicles,” said Grimpe.
Cold Comfort in the Arctic
The Aitik copper mine, also located in Sweden’s Arctic region, is the largest open-pit mine in Europe. More than 18 million mt of ore are mined annually, and mine owner Boliden’s intention is to double pro-duction to 36 million mt by 2014. Along with increased production, the expansion activity at Aitik has brought a new, more efficient and cost-effective method for transporting copper concentrate at the mine—a job handled by logistics firm Gällivare Frakt. To manage this task, the company bought ‘Goliath,’ a custom-built 540-hp Volvo model FH16 truck. Fully loaded, Goliath weighs 144 mt.
Gällivare Frakt transports all the copper concentrate mined in Aitik, which means every day Goliath carries 500 mt along an 8-km route from the mill to the shipping ter-minal. In addition, the truck hauls about 25 mt of silver and 1.3 mt of gold annually.
The driver, Gustav Nilsson, first weighs the empty vehicle then drives into a long, narrow corridor at the plant, where the copper concentrate is loaded. The hatches on the trailers are opened and concentrate flows into the truck from above. Controlling the truck remotely, he inches the vehicle to distribute the load evenly.
Upon arrival at the terminal, he de-ploys outriggers and empties the load, first from the towed trailer and then the truck body.
“We chose an engine with an output of 540 horsepower to match the design of the road,” said Ingemar Nilsson, Gustav’s father and a co-founder of the company. “The gradient is low from the dressing plant to the terminal, and we return with an empty truck.”
Things have changed since he started driving trucks at the mine in 1971. “When you get into this truck, you feel like you are floating on air compared with the first truck we drove,” he said. “It’s like chang-ing from a wheelbarrow to sitting on a cloud. There have been major technical developments, and it’s a question of mak-ing every ton cheaper.”
Certified a few years ago by the Guiness Book of Records as “world’s largest truck/tractor,” the Nicolas
Tractomas weighs in at 40 tons.
Tractomas Gains Traction in Mine-duty Haulage
Heavy-load/special vehicle specialist Nicolas has developed the Tractomas heavy tractor unit, which the Auxerre, France-based com-pany describes as a ‘super truck’—and its vital statistics seem to back up the claim. Measuring more than 10 m long, 3.5 m wide, 4.6 m high and weighing 40 tons, the 1,000-hp Tractomas is a custom-built machine with only the operator’s cab drawn from standard production-line assemblies, according to the company.
Earlier this year, Nicolas delivered a Tractomas model to Australia’s LCR Group, an industrial and mining services company providing ‘lift and shift’ services to domes-tic and international customers. LCR’s services include bulk material handling, transport, mining and other related tasks. The Tractomas unit is assigned to transport coal-haulage trailers at an LCR-operated coal mine in Queensland. At this operation, the truck pulls trains of up to five 87-ton-capacity, side-tipper trailers with a total weight of 535 tons. Haul distances range between 10 and 40 km and include gradi-ents of up to 5%.
According to Nicolas, Tractomas excels in this application; its 27-liter-displace-ment diesel engine enables it to reach speeds up to 10 km/h when fully loaded. On straight routes without climbs, a loaded truck can reach 50 km/h and up to 65 km/h when empty.
However, even more power is available on the Tractomas, according to Nicolas. Its PowerBooster auxiliary drive system is designed to cut-in when a need for addi-tional power is sensed. The PowerBooster feature also allows improved cooling per-formance, allowing reliable haulage even in extreme, desert-heat temperatures that can reach 50°C.
Orders for additional Tractomas units have been placed with Nicolas following delivery of the first tractor to LCR.
A version of the Tractomas that recently went into service at a Queensland coal mine routinely hauls trains of four or five coal trailers out of the pit, each trailer
rated at 87-ton payload capacity. Haul distances range between 10 and 40 km and include gradients of up to 5%