SKF deep groove ball bearing heat treatment process casting method and index

With the development of science and technology, the spindle speed of the machine tool is getting higher and higher, and the speed range is getting larger and larger, therefore, the requirements for the stability of the bearing high-speed operation are also getting higher and higher. The temperature rise of skf bearing is an important factor limiting the bearing speed. Under normal circumstances, the correct selection of deep groove ball bearing type, tolerance level, configuration mode, clearance (pre-load) size, lubricant and lubrication method can improve the high-speed performance of rolling bearings to a certain extent.

For general machine tools, the life of the spindle assembly mainly refers to its service life to maintain the accuracy of the spindle, therefore, the accuracy maintenance performance of skf bearings is required to meet the requirements of the life of the spindle assembly. For heavy duty machine tools or power cutting machines, the bearing capacity of deep groove ball bearings should be considered first. Deep groove ball bearings make precision parts, so it is required to be cautious when using, even if the use of high-performance skf bearings, if improper use, can not achieve the expected performance effect, so the use of bearings should pay attention to the following matters.

(1) dehydrogenation treatment. Deep groove ball bearing after different heat treatment process. After carbonitriding, hydrogen embrittlement is serious, bearing steel section shrinkage rate is very low, after dehydrogenation treatment, workpiece performance recovery, re-quenching workpiece no longer appear hydrogen embrittlement defects.
(2) Low temperature tempering dehydrogenation of deep groove ball bearings. With the extension of tempering time, the section shrinkage increased, and recovered to the original level after 8h tempering. In addition, hydrogen precipitation is slow in the hot-rolled structure, indicating that hydrogen embrittlement is related to the original structure.
(3) natural aging dehydrogenation. When the hydrogen-containing workpiece is placed at room temperature, the supersaturated hydrogen is gradually released and the hydrogen embrittlement hazard is reduced. From the two different processing states of the workpiece, after 3 months and 6 months of section shrinkage recovery, it can be seen that the normal recovery is faster, after 3 months has been basically restored; The section shrinkage recovered obviously after 6 months of hot rolling. The method shows that the effect of natural aging on hydrogen embrittlement is significant.

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