What are the key process links in the manufacturing process of deep groove ball bearings

The processing of tube blanks is a key starting step in the manufacturing process, which directly affects the quality and performance of subsequent products. This process uses high-quality materials, such as high-carbon chromium bearing steel. After being heated to a high temperature of 1150℃-1200℃, the heated tube blank is perforated by a perforator to form a preliminary rough tube. At this stage, the heating temperature and perforation parameters must be strictly controlled to ensure the dimensional accuracy and uniformity of the internal structure of the rough tube, laying a solid foundation for subsequent processing.

Spheroidizing annealing is an important link in improving the internal structure of the rough tube. Through a specific process flow, the carbides in the steel are spheroidized, and then a uniform and fine spherical pearlite structure is obtained. This process not only reduces the hardness of the material to HRB88-94, but also significantly improves the cutting performance of the material, while effectively eliminating internal stress and preventing deformation and cracking in subsequent processing.

During the hot rolling stage of the tube blank, the shape of the rough tube undergoes an important shaping process. After the annealed rough tube undergoes secondary heat treatment, it is transformed into a rough tube through processes such as diameter reduction, wall reduction and extension rolling. In this process, the rolling temperature, deformation and rolling speed need to be precisely controlled to ensure the dimensional accuracy and surface quality of the rough pipe and meet the high standards of subsequent processing.

The recrystallization annealing process is crucial to eliminate the work hardening phenomenon. During the cold processing process, the material will be hardened due to stress concentration, which will affect the subsequent processing performance. Recrystallization annealing can eliminate the hardening effect and restore the plasticity and toughness of the material by rearranging the internal grains of the material, thus ensuring the smooth progress of subsequent processing procedures such as cold rolling.

Cold rolling expansion kit is a key process for manufacturing the groove of deep groove ball bearings. During the cold rolling process, the feed speed of the core roller is divided into multiple stages, and the speed range, rolling time, rolling force and other parameters are carefully designed and adjusted. Through the precise control of these parameters, a uniform hardened layer is formed on the surface of the groove, which significantly improves the hardness and wear resistance of the groove, while ensuring the shape accuracy and dimensional accuracy of the groove, ensuring low friction and long life of the bearing during operation.

In the soft grinding kit link, the end face and outer circle of the kit are precisely processed. First, the double end faces of the kit are soft ground by through-grinding to ensure that the outer diameter surface of the part and the support plate are on the same plane, and the outer diameter taper is controlled within the specified range. At the same time, by adjusting the angle relationship between the grinding wheels, the parallel difference of the end faces is accurately controlled to ensure the end face accuracy as the reference surface for subsequent processing. The outer circle is processed by centerless grinding technology to ensure its cylindricity, thereby improving the assembly accuracy and operation stability of the kit.

The fine hole and turning process of the kit further improves the overall accuracy and performance. At this stage, the stop bolt hole and oil hole are drilled on the surface of the kit, and the inner hole surface of the kit is rough-turned to prepare for the cold rolling of the inner hole surface. During the turning process, the chamfering and sealing groove processing of the kit are also completed in this link, which optimizes the kit structure and improves the sealing performance and assembly convenience of the bearing.