A road train is an Australian trucking concept which is used for highly efficient transportation of various loads. As highly efficient, this concept is also used in some remote areas in United States, Argentina and Mexico. However, the road trains are a vital part of the Australian transportation industry, and they can be found all over Australia. The road train can be also described as a tractor unit (prime mover) that pulls two or more trailers. The road trains are also known as B double trailers and are classified in few categories. It is stated that the heaviest (up to 200 tonnes) and longest road-legal B double trailers (up to 26m) can only be seen in Australia.
The sole purpose of the B double trailers is to ensure a safe and highly efficient transportation of different materials. While the conventional transportation services and vehicles are expensive, the transportation costs of the B double trailers are affordable for all transportation companies. These heavy-duty transportation units can deal with all types of loads and are perfect for transporting secured loads (vehicles, timber, pallets, etc.). The B double trailers are commonly used for transportation of loads in harsh environments. Also, they are available in different trailer configurations. They can be matched with semi-trailers, pig trailers, so-called dog trailers and converter dollies.
These huge transportation vehicles do not mix well with normal traffic and cannot travel on all roads. Unlike the traditional trailers, the B double trailers feature a fifth wheel coupling at the end of each trailer, which increases the stability. Each trailer has a turntable at the end in order to be attached to another semi-trailer. Basically, a B double trailer is a a standard truck with two semi trailers, but when another articulated trailer is attached, the end result is a B triple trailer.
For transportation of fuel, ore and cattle, the B triple trailers are more efficient than the B double trailers, because they offer more capacity. However, the B double trailers are still a more popular choice than any other trailers. But when loaded with loads that exceed 150 tones, a B double trailer cannot stop quickly, even at low speeds. Therefore, the drivers need to be extremely cautious on the road when operating with B double trailers.