With many mining companies across Australia opening up satellite pits that are located over 10km from the processing plant or railway line, the cost of hauling material is becoming a major issue. Costs for such haulage can often be excessively high, yet they can be reduced with the appropriate planning and management.
Often, one of the start points with such haulage is to use the big rigid dump truck with 100 tonne plus capacity. However, it is these very vehicles that can present some of the extra costs.
First, their haul range is usually restricted to around 5km so, in response to that limitation, road trains ? essentially a prime mover such as a big on-highway truck pulling two or three trailers ? are presented as an answer. But put such vehicles or even on-highway vehicles to work on rough haul roads and the problems of excessively high maintenance emerge.
?Rough roads can rattle the suspension and brakes to pieces,? explained one road train operator.
?The brakes soon get out of kilter with the vibrations, and the suspension, if not specifically designed for off-highway use, can result in various components rattling to pieces. We?ve had bolt-on items fall off, cracks occur in the cabin and radiator, mirrors lose their adjustment, to name just a few of the problems.
?A chattering suspension and the skipping, when going back empty, can create extraordinarily high maintenance costs and more driver fatigue,? the operator added.
THE ROAD TO COST-SAVINGS
The solution to this series of operating problems and costs is a haul truck specially designed and built for off-highway use, on mine sites in particular.
Tasmanian-based specialist manufacturer Haulmax has released its latest 3900 series truck. Built specifically for work on off-highway haul roads and developed out of its earlier models, it presents the answers. The 3900 is already in service, with two units operating for Rio Tinto Iron Ore in Western Australia?s Pilbara region.
Bob Calvert, Haulmax?s global marketing manager, admits that the company?s special design for off-highway use represents a higher capital cost than modified on-highway trucks but he says the payback ? ?They are designed to last two to three times longer? ? is a significant advantage.
The 3900 is offered in three configurations: a dump truck with a payload of 80 to 85 tonnes, a trailer unit with a payload of 130 to 135 tonnes or a 150 to 190 tonne capacity road float. It is offered as an ideal base for the mounting of service modules, a fuel tanker or a water cart.
Bob Calvert said the 3900 haul trucks were built around a complete Caterpillar powertrain. Ninety-five per cent of the serviceable parts used in the trucks are from Caterpillar and the Cat dealer network can support them.
?They all have proven Caterpillar components ? the radiator, engine, torque convertor, powershift transmission, differentials, final drives, wet disc brakes and hydraulic suspension which is nitrogen-over-oil cylinders on each of the front wheels and dual cylinders on each of the rear axles.
?Together with oil-cooled multiple wet disc brakes on both rear axles, we have been able to get on top of the issues of maintenance and repair costs seen in ?on-haul? haulers.
?And we have designed and built our own axle system for long distance haulage. This puts our range out to 50km cycles.?
According to Bob Calvert, the feedback from mine managers and haulage operators is that the 3900 fills a void that existed in the market ? the space between the traditional dump trucks with their limitations of a 10km range and road trains powered by prime movers built for on-highway applications, whose mix of components from different manufacturers makes servicing and repair work at distant sites more tedious and costly.
ROADS KEY TO COST REDUCTIONS
The nature of the haul roads is another area in which the Haulmax 3900 series represents a major saving. The big conventional rigid frame dump trucks of 100 tonnes plus capacity require haul roads of at least 18m wide. By comparison, the Haulmax trucks have a narrow wheelbase that only requires a road width of about 13m ? 30 per cent narrower and representing major savings in the cost of construction, maintenance and other lesser activities such as dust suppression. The longer the haul road, the greater the saving.
Bob Calvert said customers were also attracted to the Haulmax truck because of the company?s pedigree. He pointed out that Haulmax first started working with Caterpillar seven years ago when it adopted the exclusive use of the whole Caterpillar powertrain. That arrangement continues today and is ongoing. More recently, mining industry identity and prominent mining equipment manufacturer Dale Elphinstone has become a large shareholder in Haulmax. These strong tie-ups attach an added sense of integrity to the company.
Source: Northfield Communications/Haulmax Pty Ltd