For semi-trailer owners, the main source of profit is freight. The longer the body, or the higher the fence, the more goods they can load. Many car owners who are ready to change consider how to make the car as long as possible, but they are afraid that they will not be able to get the license plate after they buy it. So, under the current standard, how many meters can a semi-trailer be long?

According to GB 1589-2016 outline dimensions, axle loads and mass limits of automobiles, trailers and motor trains:

1. The length limit of one axle is 8.6m, the length limit of two axles is 10m and the length limit of three axles is 13m for the semi-trailer of barrier type, warehouse grid type, flat type and dump type;

2. The length limit of other semi trailers is 13.75m, and the length limit of semi trailers transporting containers is 13.95m;

3. The length limit of center axle and drawbar trailer is 12M, of which the length limit of carriage is 8m (except for the transportation trailer of center axle vehicle);

4. The length limit of hinged train is 17.1m, and the length limit of long head hinged train is 18.1m;

5. The length of freight train is limited to 20 meters, and the length of central axle vehicle transportation train is limited to 22 meters.

From the perspective of regulations and standards alone, the central axle, especially the central axle vehicle transportation train, which is often referred to as the sedan car, is more advantageous. It is specially used for the transportation of passenger cars. Its length can be up to 22 meters, which can be 5 meters longer than the hinged train, that is, the main vehicle + semi-trailer.

Don't underestimate the 5 meters. It's used for cargo transportation, but it's not a small space. But is the central shaft worth buying? Let's analyze its advantages and disadvantages in detail.

Advantages of mid axle vehicles:

1. The vehicle chassis is lower.

As we all know, the traction power of the semi-trailer comes from the tractor, which is different from the middle axle trailer. Its power comes from the truck chassis in front. Therefore, its towing hook is usually set on the chassis of the front vehicle, which is lower than the traction pin of the semi-trailer in terms of height. Therefore, the chassis of the middle axle trailer can also be made lower.

As soon as the chassis becomes shorter, many advantages are highlighted: lower center of gravity, more stable vehicle and better operation safety; In case of roads with high upper limit, the trafficability of vehicles is stronger; For the center axle car, the low chassis means that it can be stacked up and down in double rows, with larger capacity.

2. Longer vehicle length.

As we mentioned just now, if the length is long, there will be more goods loaded. Needless to say.

3. Strong curve trafficability.

The wheels of the center axle trailer are in the middle of the carriage, so the wheelbase is shorter and the turning radius is smaller. In case of a relatively small curve, the semi-trailer can't turn, but the center axle trailer may be able to turn. Therefore, under the same turning radius, the center axle trailer can be made longer.

Disadvantages of mid axle vehicles:

1. The product is not mature enough.

The wheels of the center axle trailer are in the middle of the carriage, which is easy to swing up and down or left and right, which affects the driving stability of the vehicle to a certain extent. In addition, there is almost no gap between the front vehicle and the cargo compartment of the center axle trailer. Once the front vehicle needs braking, the rear compartment will push forward due to inertia. If there is a fierce collision, the cab cannot move back, and the safety is worrying.

2. The price is on the high side.

Compared with semi-trailer, the vehicle cost of center axle trailer is higher. For example, if the semi-trailer body is broken, you can directly replace it with a new one, but the front of the middle axle trailer is matched with the body. If you want to replace it, you must consider the matching, which virtually increases the vehicle cost.

3. High requirements for road conditions.

The chassis of the center axle trailer is lower. Although it has advantages on the height limited road, at the same time, the low chassis can easily lead to the vehicle being unable to adapt to bad road conditions.

In addition, it is not a disadvantage, but only a constraint, that is, the driver of the center axle trailer must have an A2 driver's license or above. After all, there are still many differences between the driving of the center axle vehicle and the semi-trailer.

Perhaps it is also because of these reasons. Although the center axle trailer is favored by many car owners, there has been no major movement in the market. However, as the current "green brand" model of regulations, coupled with the modularization and standardization trend of the transportation market in the future, the center axle vehicle still has a certain development prospect in the domestic logistics industry.

No matter what kind of transportation model, it also needs to be matched with high-quality axles in order to give better benefits in the transportation field. Shandong Darong group is the first axle enterprise to mass produce integrated axles in Liangshan commercial vehicle production base. It has changed the traditional three joint welded axle body, and the heavy load performance of the axle has been greatly improved. Darong's disc axle, drum axle, concave axle, three wire six axle axle, special axle and other product series are rich, In the past 20 years of operation, with stable and reliable quality and ultra-high cost performance, it has established good cooperative relations with many Trailer enterprises, logistics companies, transportation fleets and retail investors to help car owners reduce the cost of comprehensive vehicles and achieve energy conservation, efficiency and emission reduction.