Product Description：

A  fifth wheel coupling provides the connection between a semitrailer and a tractor, towing vehicle, lead trailer or trailer carrier. The coupling consists of a kingpin, a 2-or-3+1⁄2-inch-diameter (50.8 or 88.9 mm) vertical steel pin protruding from the bottom of the front of the semi-trailer, and a horseshoe-shaped coupling device called a fifth wheel on the rear of the towing vehicle. As the connected truck turns, the downward-facing surface of the semi-trailer (with the kingpin at the center) rotates against the upward-facing surface of the fixed fifth wheel, which does not rotate. To reduce friction, grease is applied to the surface of the fifth wheel. The configuration is sometimes called a turn-table in Australia and New Zealand, especially if it is a rotating ball-race-bearing type. The advantage of this type of coupling is towing stability.

Some camper trailers also use a fifth-wheel configuration, with the coupling installed in the bed of a pickup truck as a towing vehicle; "fifth wheel" is therefore sometimes used as a synonym for such campers.

Product Parameters：

Application：

The term "fifth wheel" can refer to several different applications depending on the context:

1. Trucking and Trailers: In the context of trucks and trailers, a fifth wheel is a coupling device mounted on a tractor or truck that connects to a semi-trailer. It allows for articulation and pivoting between the tractor and trailer, enabling easier maneuverability and turning.

2. Recreational Vehicles (RVs): In the realm of RVs, a fifth wheel refers to a type of towable RV that is characterized by a raised forward section that extends over the bed of a pickup truck. This configuration provides more living space compared to traditional travel trailers.

3. Agricultural Machinery: Fifth wheels are also used in agricultural machinery, particularly large tractors and implements, where they facilitate the connection between the tractor and trailers or other implements, allowing for articulated movement.

4. Military Applications: Military vehicles and heavy equipment often use fifth wheel systems for their transport vehicles and trailers to ensure secure connections and ease of maneuverability in various terrain conditions.

In each application, the fifth wheel serves to provide a pivotal connection between two components, whether it's for transport, towing, or agricultural purposes, enhancing maneuverability, stability, and ease of operation.