"Looking at the turret from afar is frightening to death, and looking at five pairs of load wheels near" is a kind of stem that military fans all know. For crawler construction machinery, there is no similar stem, because the "four wheel area" of construction machinery is quite different from military vehicles. For construction machinery, such as excavators, the roller is usually small, not only that, but also often wrapped. Although it can be counted several pairs in recent years, the number is the axle of the supporting load, and the roller is almost invisible. Of course, most excavators can see the roller directly, only one branch heavy wheel is wrapped.
Several pairs of rollers can be counted, but the rollers cannot be seen.
So, why do the roller need to be wrapped up, and why are there more and less? Originally, the supporting wheel was wrapped up, called chain guard plate, chain guard, rail clamp. Here, it is called chain rail guard plate. The significance of its existence is to prevent derailment.
Small excavators usually have only one pair installed
Different from military vehicles, most of the construction machinery has no suspension system for the sake of working stability. The weight of the vehicle body is rigidly transmitted to the ground, and the roller is fixed on the track roller frame. Due to no suspension, the roller can not keep close contact with the track track at all times.
Medium sized excavators are usually equipped with two or three pairs
In order to prevent derailment, our common "four wheel and one belt" system has track tensioning device, on the other hand, it also relies on the wheel rim of the roller. However, the diameter of the supporting wheel is not large, and the flange is not high, so it is better than nothing. Crawler construction machinery, such as excavator, is realized by the speed difference between the two tracks when turning. Therefore, it is inevitable that the track will have lateral friction on the ground. When the crawler is subjected to unbalanced lateral force, it is easy to make the chain track and some supporting wheel stagger, which will eventually lead to derailment.
There are still others like this.
The installation of chain rail guard plate can effectively improve the anti derailment ability of the track, which is equivalent to adding high wheel flange to some supporting wheels. Even under large lateral force, the chain rail is difficult to escape from the chain rail guard plate. As for the quantity of installation, it depends on the working conditions. If it is a relatively uniform earthwork condition, the risk of derailment is not large. Therefore, some small excavators with earthwork conditions are usually installed with only one pair, while the medium-sized excavators with general working conditions will generally install two or three pairs. Equipment with blasting rock conditions, such as large-scale excavators, will be installed with full range Long guard board, that is, all inclusive way. Because the crawler is walking on a big rock, the lateral force on the track will be very large and uneven.
It is impossible to make the supporting wheel flange very high. The chain rail guard plate is equivalent to increasing the flange height.
Of course, not only excavators, but other crawler equipment, such as bulldozers, have similar problems. The bulldozer works by walking, so it has higher requirements for anti derailment. Generally, the full-length guard plate is used. In fact, the chain rail guard plate on the excavator is transplanted from the bulldozer. Is there any defect in the chain rail guard? Of course, there are also. If the operation is improper, it is easy to get stuck in foreign matters. At the same time, it is not convenient for the driver to find out the problems of the roller in time, and the maintenance of the track and roller also increases the trouble.