Online 24 hours a day
|
|
Casting method for heat treatment process of deep groove ball bearingsWith the development of science and technology, the spindle speed of machine tools is getting higher and higher, and the range of speed change is becoming larger and larger. Therefore, the requirements for the stability of high-speed operation of bearings are also becoming higher and higher. Bearing temperature rise is an important factor limiting bearing speed. In general, selecting the type, tolerance level, configuration method, clearance (preload) size, lubricant, and lubrication method of deep groove ball bearings correctly can improve the high-speed performance of rolling bearings to a certain extent. For general machine tools, the lifespan of spindle components mainly refers to the service life of maintaining spindle accuracy. Therefore, it is required that the accuracy maintenance performance of bearings meet the requirements of spindle component lifespan. For heavy-duty machine tools or powerful cutting machines, the load-bearing capacity of deep groove ball bearings should be considered first. Deep groove ball bearings are precision parts, therefore a cautious attitude is required when using them. Even if high-performance bearings are used improperly, the expected performance effect cannot be achieved. Therefore, when using bearings, the following precautions should be taken. (1) Dehydrogenation treatment. Deep groove ball bearings undergo different heat treatment processes. After carbonitriding, hydrogen embrittlement is severe, and the cross-sectional shrinkage rate of bearing steel is very low. After dehydrogenation treatment, the performance of the workpiece is restored, and after re quenching, the workpiece no longer shows hydrogen embrittlement defects. (2) Deep groove ball bearings undergo low-temperature tempering and dehydrogenation. As the tempering time prolongs, the reduction of area increases, and after 8 hours of tempering, the reduction of area returns to its original level; In addition, the slow precipitation of hydrogen in the hot-rolled microstructure indicates that hydrogen embrittlement is related to the original structure. (3) Natural aging dehydrogenation. When the workpiece containing hydrogen is placed at room temperature, the Supersaturation hydrogen is gradually released and separated, and the hydrogen embrittlement hazard is reduced. From the recovery of cross-sectional shrinkage rate of workpieces treated with two different processes after 3 and 6 months, it can be seen that the normalized state recovers quickly and has basically recovered after 3 months; After 6 months of hot rolling, the cross-sectional shrinkage rate significantly recovered. This method indicates that natural aging has a significant effect on eliminating hydrogen embrittlement. |