A semi-trailer truck (more commonly semi truck or simply “semi”) is the combination of a tractor unit and one or more semi-trailers to carry freight. A semi-trailer attaches to the tractor with a fifth-wheel coupling (hitch), with much of its weight borne by the tractor. The result is that both the tractor and semi-trailer will have a design distinctly different from that of a rigid truck and trailer.
It is variously known as a transport in Canada and big rig, or eighteen-wheeler in the United State.
BGX Transport operates fleets of semi-trailer trucks.
- tractor unit
- semi-trailer (detachable)
- engine compartment
- cabin
- sleeper (not present in all trucks)
- air dam
- fuel tanks
- fifth-wheel coupling
- enclosed cargo space
- landing gear – legs for when semi-trailer is detached
- tandem axles
