summary
The four wheel in the "four wheel belt" refers to the driving wheel, guide wheel, top roller, supporting wheel and belt refers to track chain
They are directly related to the working performance and walking performance of excavator, and its weight and manufacturing cost account for one quarter of the cost of excavator manufacturing.
track chain
Classification: there are two types: one is integrated and the other is combination.
The integral track is a rolling track with meshing teeth on the track plate, which tends to engage with the driving wheel. The track plate itself becomes the rolling track of the wheel such as the roller.
Features: easy to manufacture, but wear fast.
Now, the excavator is characterized by its small pitch, good rotation and fast walking speed. Long service life.
The track plate used is mainly light weight, high strength, simple structure and cheap rolling plate. There are several kinds of single bar, double bar, three bar and so on.
Now, the excavator is mostly made of three bars. The features are: the height of the reinforcement is small and the strength of the track plate is large. Smooth movement, low noise.
There are generally four connecting holes on the track shoe, and two mud cleaning holes in the middle to automatically remove the clay. There is a lap between the two similar track shoes to prevent the damage caused by the middle clamping stones.
The excavator on wetland can use triangle track shoes, whose cross section is triangle, which can compress the soft ground and improve the support capacity.
Driving wheel
The power of the engine of hydraulic excavator is transmitted to the track through the walking motor and the driving wheel. It is required that the drive wheel and the track chain be engaged correctly and smoothly. Moreover, the track can still be well meshed when the track is extended due to the wear of the pin sleeve.
The drive wheels are usually located at the rear of the excavator travel device.
According to the structure, it can be divided into: integral type and split type
According to pitch, it can be divided into: equal pitch and unequal pitch
Material: 50Mn, 45simn, and make its hardness reach hrc55-58
Supporting wheel
The function of the roller is to transmit the weight of the excavator to the ground. When the excavator is running on uneven road, the roller will be impacted by the ground. Therefore, the roller is loaded heavily, the working conditions are bad, and it is often in dust and sometimes soaked in mud water, so it is required to have a good sealing.
Material Science:
35MN and 50Mn are used to make it more. The hardness of the wheel surface was hrc48 and 57, so as to obtain good wear resistance.
characteristic:
The sliding bearing is used to support the system. And use floating oil seal to prevent dust.
In a overhaul period, only one time of butter is added, which simplifies the maintenance work of excavator.
Guide wheel
The guide wheel is used to guide the track to rotate correctly to prevent its deviation and derailment.
Most excavators also play a role as a roller. This can increase the contact area of track to the ground and reduce the specific pressure of the ground.
The wheel surface of the guide wheel is made of smooth surface, and the middle part has a stop ring as the guiding function, and the ring surface on both sides supports the rail chain.
The smaller the distance between the guide wheel and the nearest roller, the better the guiding performance.
Material: 40, 50 steel, or 35MN, casting attainment, tempering treatment, hardness hb230-270
main points:
In order to make the guide wheel play a role and prolong its life, the radial runout of the wheel facing the center hole shall be less than or equal to 3mm, and the correct alignment shall be made during installation.
Top Roller
The function is to hold the track upward to make the shoe have certain tension.