An axle on a HGV (Heavy Goods Vehicle) is a structural component that connects the wheels of the vehicle to the frame. The main function of an axle is to transfer the weight of the vehicle and its load from the frame to the wheels, and to transfer the power from the engine to the wheels to drive the vehicle.

There are two main types of axles used on HGVs: single and tandem. A single axle is one that has only one wheel on each side, while a tandem axle has two or more wheels on each side. Tandem axles are used in vehicles that need to carry heavier loads, as they distribute the weight over more wheels and therefore reduce the stress on each individual wheel.

Axles also have different configurations depending on their location on the vehicle, such as steerable axles, drive axles and non-steerable axles. Drive axles are responsible for providing drive to the wheels, while steerable axles are used to steer the vehicle. non-steerable axles are used to support the weight of the vehicle.