Mining Haul Truck

Overview

A mining haul truck is an off-highway rigid dump truck built to move overburden and ore in large open-pit operations. The ultra class carries roughly 400 tonnes per load. Unlike highway trucks it uses a diesel-electric drive: a diesel engine generates electricity that powers traction motors in the rear wheels, avoiding a heavy mechanical transmission and giving precise, stepless speed control on long ramp hauls.

Everything mounts on a Chassis Frame, a deep welded box-section steel chassis with cast nodes at the highest-stress joints. The Dump Body sits on pivot pins at the rear and is raised by hydraulic hoist cylinders to tip the load.

How it works

The V20 Diesel Engine is a high-displacement V20 prime mover. Rather than turning the wheels mechanically, it drives the AC Electric Drive System system. Within it the main alternator produces AC, a rectifier feeds a DC link, and traction inverters synthesise variable-frequency power for the two Electric Wheel Motor units in the rear hubs. Each motor drives its wheel through a Planetary Final Drive planetary reduction.

Slowing the loaded truck is largely electrical: the wheel motors act as generators and the energy is burned off in a dynamic retarder grid, sparing the friction brakes on long descents. Final stopping and holding is handled by the oil-cooled Oil-Cooled Brake System, a wet multi-disc pack at each wheel.

The truck steers through the Front Axle & Steering and rides on four oleo-pneumatic Oleo-Pneumatic Strut cylinders that cushion the unsprung mass over haul-road irregularities. Body hoist, steering and brake cooling all draw from the Hydraulic System. The operator works from a ROPS-rated Operator Cab, while the Electrical System system runs low-voltage controls, lighting and a vehicle health monitor that logs payload, strut pressures and drivetrain condition.