Modern Mining July 2015

OFF-HIGHWAY TRUCKS AND EXCAVATORS

Several decades ago, mine owners andmining contractors had little choice in the equipment used to haul material in open-pit operations. In essence, they were limited to using either rigid frame trucks (rigids) or – in the right conditions – scrapers. Nowadays there is a third option – the articulated dump truck or ADT, first introduced in the 1960s. Initially mainly deployed in civil earthworks applications, the ADT has been increasingly used inmining since roughly the 1980s. To learnmore about this versatile tool, which is now the dominant hauler in small tomedium- sized open-pit mines, ModernMining’s Arthur Tassell recently spoke to Terry Gillham (right), Director: Sales andMarketing of Bell Equipment, one of the world’s leadingmanufacturers of ADTs and almost certainly the market leader for this class of machine in Southern Africa. Versatile ADTs now dominant in

T here is an obvious dividing line between ADTs and rigid trucks based purely on payload capacity. Currently the world’s biggest ADT is the Bell B60, which – as its des- ignation suggests – can take a 60-ton (54-tonne) load. While this capacity has taken the ADT concept into new territory, it nevertheless falls well short of what is required in large open- pit-mines, where 100-ton, 150-ton and 200-ton machines are the norm. Capacities go up even higher than this and trucks of 240 tons and above are the machines of choice in the new generation of ‘super-pits’ around the world (several of which are in Southern Africa). Most

of the big rigid dump truck manufacturers have ranges which now top out at 400-ton payload capacity and one – Belaz in Eastern Europe – even produces a 450-ton machine. Says Gillham: “Where the interesting overlap occurs is in the space which was once catered for by rigid trucks in the 35-ton to 60-ton class. This market has now been taken over by ADTs. You can still see rigids of this size at mines but they are increasingly rare and have suf- fered a significant loss of market share. The primary reason for this is that the ADT – with its all-wheel drive and articulated joint – is an incredibly versatile machine. It can handle both short and relatively long hauls, good and

The Bell B60 is the biggest ADT in the world. These three Bell B60Ds are working at an open-pit coal mine in South Africa but full commercial production of the B60 is only due to start with the E-series in 2017.

feature

46  MODERN MINING  July 2015