14 January 2015, 00:00
The world's biggest dump truck can transport more than 500 metric tons of material — that’s equivalent to seven fully fueled and loaded Airbus A320-200 planes. The truck is driven by four 1,200 kW electric motors from Siemens.
How do you get the world’s biggest truck rolling? BelAZ, a Belarusian vehicle manufacturer, came to Siemens with this question in 2011. BelAZ was looking for an electric drive for its new dump truck, which would weigh 360 metric tons unloaded. The new truck was to transport loads weighing over 500 metric tons — equivalent to more than 350 VW Golf cars or seven fully loaded Airbus A320-200 planes — or about 25 percent more than the previous holder of the “world’s biggest dump truck” record. Plans also called for the new truck to carry its load at a lower cost per ton of transported material and to have a top speed of 64 km/h when it's empty.
Companies that do underground and open-pit mining must not only adhere to environmental regulations but also consider costs. That’s why trucks used in this industry must be absolutely reliable and productive. Siemens has been developing drive systems for dump trucks for about 15 years, always with the goal of finding ways to make these giants of the mines more efficient.
Electric Drive
One example of efficiency in this area is the development of “trolley trucks,” which get their electricity from overhead power lines. This innovation made it possible for such trucks to almost double their speed, even on steep ramps. But the challenge presented by BelAZ was something new for engineers at Siemens Drive Technologies. They were asked to develop an electric drive that would move a truck with a gross vehicle weight of up to 810 tons and would ensure that this truck was able to transport mined material quickly and reliably. In addition, the project was on a relatively tight schedule. The interval between the inquiry from the customer and the commissioning of the first truck was less than two years. In contrast to the previous model, the new truck was to be outfitted with eight tires, because each tire is designed to carry a load of about 100 metric tons.
With this in mind, Siemens’ traction-drive experts in Nuremberg settled on developing a reliable and powerful all-wheel-drive system that uses four electric motors. A tried and tested drive system served as the model for the new system. The engineers also developed a new control solution. All of the electric drive’s components came from Siemens. This ensured that all the elements would work together perfectly.
No Towing Required
The all-wheel-drive configuration provided the engineers with new possibilities, such as dynamic power distribution between the truck’s two axles. Moreover, if one of the electric motors were to fail, the truck would still have emergency drive capability, meaning that it could be driven to a workshop under its own power — in other words, it doesn’t have to be towed or left to block a ramp, for example. The system uses two 16-cylinder diesel engines, each with an output of around 1,700 kW. Together, they provide the energy that the electric drive requires.
The truck was unveiled to the public in October 2013. It is over 20 meters long, almost ten meters wide, and around eight meters tall. Its all-wheel drive and four-wheel hydraulic steering ensure that the tires, which are around four meters tall, don’t get stuck in rough terrain. The truck is now being tested at an open-pit coal mine in Siberia, and sales of the vehicle are expected to begin later this year. After that, it will be used primarily to transport coal and iron ore-bearing rocks.