Overview of Tractor unit and Ballast tractor

Tractor rigs (also known as truck rigs, powerplants, prime movers, ten-wheelers, semi-tractors, towing trucks, semi-trucks, tractor cabs, truck cabs, tractor rigs, truck rigs, or big rigs or simply tractors, trucks , semi-trailer, or rig) is a typical heavy-duty traction engine that provides power to tow a trailer or trailer load.These fall into two categories: heavy-duty and medium-duty military and commercial rear-wheel-drive semi-tractors used to tow semi-trailers, and extra-heavy, usually 6×6, military and commercial tractors, often with off-road capability, including ballast tractors.

Overview 

Tractors are typically equipped with a large displacement diesel engine for power, durability and economy; several axles; and a multi-ratio transmission (10, 13 or 18 gears) for maximum flexibility in gearing.A tractor-trailer combination distributes the load across multiple axles while being more maneuverable than a rigid truck of the same size.The most common trailer hitch system is the fifth wheel coupling, which allows quick switching between trailers performing different functions, such as bulk dump trucks and box trailers.Trailers loaded with different loads can be quickly swapped between tractors, eliminating downtime when trailers are unloaded or loaded.Drawbar couplings are also found, especially in dedicated extra-heavy-duty ballast tractors, as a way of connecting the middle five-wheel trolley to tow multiple semi-trailers.

Ballast tractor

Ballast tractors are special counterweight tractors combined with heavy transport vehicles.It is designed to pull or push heavy loads or oversized trailer loads loaded in hydraulic modular trailers using the drawbar.Where practical, use a low profile semi-trailer to minimize the load's center of gravity.Typical drivetrains are 6×4 and 6×6, but 8×6 and 8×8 are also available.Typical ballast tractor loads include oil rig modules, bridge sections, buildings, ship sections, and industrial machinery such as generators and turbines.Only a few manufacturers produce dedicated ballast tractors.The super-heavy chassis version of the production tractor unit is equipped with a drawbar hitch and a separate ballast box as an alternative.These units are classified as category N3 large goods vehicles.The history of ballast tractors dates back to the 1940s when heavy trucks started using purpose built ballast tractors.Remotely controlled, self-propelled modular transport vehicles (SPMTs) are increasingly being used in traditional ballast tractor/trailer roles.