PRODUCT FOCUS
Volvo CE
The conversion to electric power is likely to reduce the amount of energy used by 71 % and cut CO 2 emissions in the targeted quarry site from the current 0.7kg / tonne of material produced to 0.3kg / tonne.
ELECTRIC ECONOMY –
THE FUTURE OF OFF-ROAD TRUCKS
By Robyn Grimsley
While outwardly off-road trucks may appear to have changed very little over the past century, the real change is taking place inside, under the hood.
Articulated dump trucks( ADTs) and rigid dump trucks( RDTs) are a staple of the mining industry and have been around in one form or another for close to a century. Since the introduction of the world’ s first off-road dump truck— Euclid Road Machinery’ s Model 1Z— in 1934, and Volvo’ s 10-ton 4 × 4 DR 631 ADT, nicknamed‘ Grus- Kalle’( Gravel Charlie) in 1966, there have been significant improvements to the design of these machines. Today’ s ADTs have articulated steering, all-wheel drive, and differential locks, giving a tighter turning radius for improved manoeuvrability and making them the best option for navigating soft ground.
One of the big changes has been in the size of the machines. According to Equipment World 2016, over the past decade alone, sizes have increased significantly. In 2006, the largest ADT was Cat’ s 42-ton 740. In 2016, 50 years after introducing the world’ s first ADT, Volvo introduced the largest: the 60-ton A60H. This represents an increase of a ton per year since the original 10-ton machine was first introduced, and an increase of 18 tons in just 10 years. And RDTs are even bigger. Today, the largest off-road dump truck is the BelAZ 75710, an ultra-class RDT manufactured in Belarus with a payload capacity of 450 tonnes. Not far behind this are the Caterpillar 797F, the Terex
MT6300AC, and the Liebherr T282B, with a payload capacity of 400 tonnes.
But perhaps the biggest change that has occurred over the past century— and which is continuing— is the move away from diesel-driven machines towards hybrid and purely electric machines. While hybrid machines operate in different ways, most have a fully mechanical drivetrain— engine, gearbox, driveshafts, and wheels— and an electric motor. This motor runs off a battery pack and provides additional power when the operator calls for maximum power, and then provides braking force when the operator wants to slow down. When braking, the motor turns into a generator and charges the battery pack.
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JANUARY 2018