Log Transport
The type of truck and trailer used to transport logs is dependent on the size of logs being transported, the condition of the roads, and regional preferences.
Tree Length Log Trucks
Full-length logs can be transported by stinger-steer log trailers or fixed length log trailers.
Pole trailers were designed to minimize the overall tare weight of the truck. It is limited to working with tree length material. The stems are not supported in the middle, just between the bolsters at either end.
The trailer is typically a set of double-axle wheels with a rotating bunk. As the truck turns the length of the stems is fixed between the bolsters, but the distance between the truck and trailer must elongate. The pole connector must therefore be telescoping. A slight variation on the pole trailer is the stinger-steer trailer, specifically designed for turning on roads with tight turning radii.
Stinger-steered log trailers consist of a tractor with a log bunk mounted over the fifth wheel. This log bunk is capable of rotating on the fifth wheel. A second set of bunks is mounted on a pair of axles and is capable of rotating. The tractor has a bar extending from the back, called a reach, with a pintle hitch. The rear bunks have a steel bar, called a stinger, that consists of a telescoping bar so that the distance between the tractor and trailer can change as needed. The stinger attaches to the reach to complete the trailer. The advantage of a stinger-steer is that the trailer wheels follow the path of the tractor wheels when going around corners. This permits operation on roads with tight corners.
Figure 1 - Truck and pole trailer.
Fixed length log trailers are simply a semi-trailer with bunks instead of a box. They do not have a floor, but one or more beams to support the bunks along the length of the trailer. They are capable of carrying tree length logs or multiple bunks of log length material. For transportation on public roads chains or straps will have to be used to secure the logs in the bunks from sliding or rolling off.
Figure 2 - Semi-truck double bunk trailer.
Log Length Log Trucks
Where only log length material is being transported, a straight truck with a trailer may be used. Often the straight truck has a loader mounted on the rear of the truck for self-loading.
Figure 3 - Semi-truck double bunk trailer.
Indexing logs on a log truck may be used to achieve the full capacity of the log truck. This is done by placing logs top to butt and is especially effective where the logs have high taper.
Figure 4 - Straight Truck with Indexed Load.