The national standard for semi-trailer dimensions is: length not exceeding 17.5 meters (including tractor), width usually 2.5 meters (special specifications can reach 3 meters), height limit 4 meters (closed box truck can reach 4.2 meters)
The following is a detailed classification description of semi-trailer dimensions:
1. Length standard
Total length limit
When including the tractor, the total length of the semi-trailer shall not exceed 17.5 meters; the maximum length of a single vehicle (trailer part only) shall not exceed 14.6 meters (closed box truck) or 13.75 meters (ordinary type).
For special models such as semi-trailers transporting 45-foot containers, the maximum allowable length is 13.95 meters.
Common classification lengths
Van trailer: 11m, 12m, 13m, 14.6m
Warehouse type: 9.5m to 13m (such as 9.5m, 11m, 12.5m, etc.)
Low-bed trailer: 9.5m to 16m (gooseneck or special series)
Container type: 7.3m to 13.9m (corresponding to 20ft to 45ft containers)
II. Width and height standards
Width
The conventional width is 2.5m, and the closed van is allowed to be 2.55m;
Special purpose vehicles (such as over-bottom flatbed semi-trailers) can be expanded to 2.8m~3m.
Height
Ordinary semi-trailers are limited to 4m, and closed vans can reach 4.2m;
The height after loading must meet road safety requirements (such as bridge height limits, etc.).
3. Other key parameters
Load capacity: Taking a 13-meter high-rail semi-trailer as an example, it can load about 29 tons of cargo and has a volume of 86 cubic meters.
Classification differences: Specialized models such as dump trucks and tank trucks may adjust their sizes due to functional requirements. For example, low-bed trucks are allowed to be wider to transport large equipment.
