Agricultural machinery grinding conditions and solutions

1、fatigue wear
Due to the long-term load alternating effect, the material of the part will break, which is called fatigue wear. Cracking usually begins with a very small crack in the metal lattice structure, and then gradually increases.
Solution: It should be noted that the stress concentration of the parts should be prevented as much as possible, so that the gap or tightness of the matching parts can be limited according to the requirements, and the additional impact force will be eliminated.
2、Plastic wear
In operation, the interference fit part will be subjected to both pressure and torque.Under the action of the two forces, the surface of the part is likely to undergo plastic deformation, thereby reducing the fit tightness. It is even possible to change the interference fit to the gap fit, which is a plastic wear. If the sleeve hole in the bearing and the journal is an interference fit or a transition fit, after plastic deformation, it will lead to relative rotation and axial movement between the bearing inner sleeve and the journal, which will lead to the shaft and many parts on the shaft changing each other's position, and will deteriorate the technical state.
Solution: When repairing the machine, it is necessary to carefully check the contact surface of the interference fitting parts to confirm whether it is uniform and whether it is in line with the regulations. Without special circumstances, the interference fit parts can not be disassembled at will.
3、grinding abrasion
Parts often have small hard abrasives attached to the surface, resulting in scratches or scrapes on the surface of the part, which we usually consider to be abrasive wear. The main form of wear of agricultural machinery parts is abrasive wear, such as in the process of field operation, the engine of agricultural machinery often has a lot of dust in the air mixed into the intake air flow, and the piston, piston ring and cylinder wall will be embedded with abrasive, in the process of piston movement, often will scratch the piston and cylinder wall. Solution: You can use the dust filter device to clean the air, fuel and oil filters in time, and the fuel and oil required to be used are precipitated, filtered and cleaned. After the run-in test, it is necessary to clean the oil passage and replace the oil. In the maintenance and repair of machinery, the carbon will be removed, in the manufacturing, the selection of materials is to have a high wear resistance, so as to promote the surface of the parts to improve their own wear resistance.
4、mechanical wear
No matter how high the machining accuracy of the mechanical part, or how high the surface roughness. If you use a magnifying glass to check, you will find that there are many uneven places on the surface, when the relative movement of the parts, it will lead to the interaction of these uneven places, due to the action of friction, it will continue to peel off the metal on the surface of the parts, resulting in the shape of the parts, volume, etc., will continue to change, which is mechanical wear. The amount of mechanical wear is related to many factors, such as the amount of load, the relative speed of the friction of the parts. If the two kinds of parts that rub against each other are made of different materials, they will eventually lead to different amounts of wear. The rate of mechanical wear is constantly changing.
At the beginning of the use of machinery, there is a short run-in period, and the parts wear very fast at this time; After this period of time, the coordination of parts has a certain technical standard, and can give full play to the power of the machine. In a longer working period, the mechanical wear is relatively slow and relatively uniform; After a long period of mechanical operation, the amount of wear of parts will exceed the standard. The deterioration of the wear situation worsens, and the parts will be damaged in a short time, which is the fault wear period. Solution: When processing, it is necessary to further improve the accuracy, roughness and hardness of the parts, and the installation accuracy also needs to be improved, so as to improve the use conditions and strictly implement the operating procedures. It should be ensured that the parts can always be in a relatively good lubrication state, so when starting the machinery, first run at low speed and light load for some time, fully form the oil film, and then run the machinery normally, so that the wear of the parts can be reduced.

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Post time: May-31-2024