The most direct and easy to understand reason is that the quality of the beam steel used by the trailer factory is not good enough to carry the designed load, resulting in the beam breaking.
First, the manufacturer's reasons.
1. The semi-trailer beam is made of inferior steel.
The most direct and easy to understand reason is that the quality of the beam steel used by the trailer factory is not good enough to carry the designed load, resulting in the beam breaking.
2. Reduce the size of the girder.
The second is that the trailer factory cut corners to save costs. The main purpose is to reduce the size of the girders. Originally, there were 14 thick vertical plates, but they were reduced to 10 thick. However, the user did not know that, but they also pulled goods according to the 14 thick bearing capacity. middle.
3. Connect the girder web.
In addition to reducing the size of the girder, some unscrupulous trailer manufacturers use two shorter steel bars to connect the webs of the girder to save costs, and the bearing capacity is definitely much worse than the whole one. Broken beam", users should pay attention to inspection when purchasing a car.
4. Welding is not good.
In addition to the fracture of the web, there are also cracks in the lower wings of the girders. There are two main reasons for this. One is the technical problem of the welder, and the other is that the voltage is unstable during welding, and the welding is not done well.
5. Unscrupulous salesmen flicker.
In fact, the reasons for so many manufacturers mentioned above, there is another point that must be paid attention to - to prevent some bad salesmen from being fooled. In order to make more money, and some to grab orders, the price is too low, and the original trailer does not make money or even loses money, so they do something about the configuration of the trailer.
The first is to reduce the configuration of the trailer. We originally talked about the configuration that can pull 50 tons. He reduced it to 30 tons for you. It is reasonable for the trailer to break the beam. Second, it is produced in a small factory that has just been built. The materials and technology of the small factory are not mature. A series of problems such as inferior steel and cutting corners may occur, and the probability of breaking the beam is greatly increased.
2. Reasons for use by users.
1. Overload or even concentrated load.
In addition to the above reasons of the trailer factory, many broken beams are caused by improper use by users. The most common reason is long-term overloading, which is easy to understand. The load capacity exceeds the designed value of the trailer, and the beam can not bear the weight of the cargo and causes it to break. Then there is the concentrated load, especially the now popular light body trailer, the concentrated load trailer is easy to break the beam.
2. Carry out the welding operation on the girder.
It is also strictly forbidden to weld on the beam of the semi-trailer. Nowadays, the beam of the trailer is mostly high-strength steel. High-strength steel is easy to anneal when encountering strong current, and the beam is easy to break after annealing.
3. The girders in mountainous areas are subject to excessive twisting force.
Trailers that often run in mountainous areas are prone to break the girders. The torsional force on the girders of trailers running in mountainous areas is much larger than that of those running on flat roads. The specifications of the upper and lower wings and webs of the girders must be larger, otherwise the girders will be easily broken.
Third, light body hanging should pay more attention.
There are also drivers and friends who use light body hangers to pay special attention. Light body hangers cannot be overloaded, let alone concentrated loads. High-strength steel beams are less flexible and are not suitable for bumpy roads. Be careful, otherwise the beams may be broken. Condition.
4. Can the reinforced beams be used?
If the tragedy of the broken beam really happens, the plan given by the trailer manufacturer is generally reinforcement, so can the reinforced beam be used? The editor asked a number of salesmen, it is best not to use it, there are too many hidden dangers.
First, the reinforced beam must be worse than the original beam in terms of bearing capacity, and it is very difficult to load the goods.
Second, it is easy to break again. Many netizens have also said that where to connect and where to break
Third, the trailer with reinforced beams is prone to tire eating.
How to avoid breaking beams.
How to prevent the semi-trailer from breaking the beam? From the above analysis of the reasons for the broken beam, when buying a trailer, choosing a reputable salesman and a large manufacturer can avoid a lot of trouble. Then you must pay attention when using it, do not overload, weld the beams privately, and pay attention to the road conditions when hanging lightly.