Truck tractors and semi-tractors are used to transport laden trailers and semi-trailers, large platforms, aircraft, faulty, non-self-propelled and other equipment. The market offers models of truck tractors from different manufacturers: from European and American brands to domestic ones. When choosing such equipment, it is necessary to know about its design features, advantages and disadvantages.
Tractor Unit Characteristics
Tractor unit is a cargo ground automobile, trackless transport on wheels or caterpillars. The main purpose of such equipment is towing trailers or semi-trailers.
Truck tractors are classified according to the following criteria:
- vehicle type;
- drawbar category;
- number of axles.
According to the vehicle type, drawbars designed to operate with trailers, and semi-tractors used to move semi-trailers are distinguished. Any vehicle having a tow coupling designed for transporting trailers can serve as a drawbar. The drawbar design includes the operator’s cab and the platform.
The drawbar pulling force is generated by the own weight of the machines. According to the number of axles, machines can be two-, three- or multi-axle ones. To tow the large-sized cargo, ballast mechanisms that have a platform for placing additional cargo (ballast) are used. The purpose of such a platform is to increase the coupling weight.
Semi-tractors are not equipped with a load-carrying body. They are connected to the semi-trailer by means of the fifth wheel coupling (saddle). Traction force that is created by the pressure of the trailer on the truck frame is transmitted through the saddle.
The most popular brands of truck tractors (that are in demand):
- European (Daf, Man, Iveco, Scania, Mercedes-Benz, Volvo, Renault).
- American (Ford, Oshkosh, Kenworth).
Regarding the cars, Japanese and Korean models, as well as special equipment, for example, port tractors can be distinguished.
Selection Criteria, Advantages and Disadvantages of Truck Tractors(Н2)
When choosing a truck, first of all, it is necessary to decide on the purpose of using the equipment (type of cargo, weight, volume, dimensions, features of the trailer or semi-trailer that will be in the coupling). The distances covered, routes of movement, choice of new or used equipment shall be also taken into account.
It is important to consider the technical characteristics of truck tractors:
- axle configuration (the most common configurations — 4х2, 6х2, 6х4);
- engine power and volume;
- engagement height;
- type of truck suspension;
- type of brake system;
- cab design.
Compared to other trucks, truck tractors have a number of advantages:
- flexibility (performing different tasks in different conditions);
- power;
- maneuverability;
- increased capacity;
- the possibility of transporting large-scale and lengthy goods;
- ease of connection with a trailer or semi-trailer.
Thanks to transportation of an increased mass of cargo per one tripusing drawbar, the cost of each ton of transported cargo is reduced. In the case of equipment breakdown, the semi-trailer or trailer can be replaced quickly and easily. The semi-tractor has the disadvantage of being less stable than common trucks. An attached semi-trailer is required for their operation.
