A semi-trailer (also known as a truck trailer) is a type of road freight vehicle that does not have a front axle. Semi-trailers are pulled by tractor trucks. A large proportion of a semi-trailer’s weight is borne by the road tractor or by a detachable front axle assembly called a dolly. A semi-trailer is equipped with legs, called dolly legs, that can be lowered to support it when unhooked from the tractor. When coupled together, the tractor and trailer combination is often referred to as a semitrailer, 18-wheeler, big rig, semi-trailer, or truck and trailer. Most of the products are transported in semi-trailers. Truck trailers are sold by independent dealers and owned by the manufacturer.
Common types of trailers
Types include dry cargo vans, refrigerated vans (reefers), flatbeds (straight bed, step bed, lowboy, double drop, etc.), and tanks. Sizes vary, but the most common sizes used today are 53′ or 48′ long; 102″ or 96″ wide; and, up to 13’6″ tall. Trailers typically carry 45,000 pounds of cargo.
A platform is not closed, without sides, without a roof and without doors. Flatbed trailers can be loaded or unloaded from the sides and do not require an elevated forklift to load in or out. Flatbed trailers are also called flatbed or platform trailers. Varieties include standard straight-floor decks, drop-decks, low decks, and other specialized decks.
A dry van is a fully enclosed vehicle. It is the most common type. Standard varieties include sheet and post construction and plate construction. Dry vans are also known as dry boxes.
Vans that are used to transport products that require temperature controls are known as refrigerated or refrigerated vans. Refrigerated containers are insulated at the nose, sides, roof, and floor. A refrigeration unit is mounted in the nose. Refrigerators are capable of maintaining sub-zero temperatures.
For more information on semi trailers, check out the American Trailer Exchange