The production process of bearing steel usually includes the following main steps:
1. Raw material preparation: The main raw materials for bearing steel are iron, carbon, and alloy elements. Before production, various alloy elements and other raw materials need to be prepared to ensure their quality meets the requirements.
2. Smelting: Raw materials undergo the smelting process, usually using an electric furnace or blast furnace, to melt and mix various raw materials to obtain appropriate composition ratios. During the melting process, by adding appropriate alloying elements and controlling the melting temperature, the composition and proportion of the alloy are adjusted to meet the performance requirements of bearing steel.
3. Refining: The melted alloy undergoes a refining process to remove impurities, gases, and other impurities, thereby improving the purity and uniformity of the alloy. Common refining methods include oxidation-reduction method, vacuum treatment, and argon gas protection method.
4. Continuous casting: The refined alloy is continuously cast into billets through a continuous casting machine to obtain the desired shape and size of the billets. During the continuous casting process, the microstructure and mechanical properties of the billet are adjusted by controlling the cooling rate and crystal structure.
5. Rolling: Continuous casting billets are processed by rolling to reduce cross-sectional dimensions and improve surface quality. The rolling process usually includes two methods: hot rolling and cold rolling, and the appropriate rolling process is selected according to different requirements.
6. Heat treatment: Bearing steel undergoes heat treatment to improve its structure and properties. Common heat treatment methods include annealing, normalizing, quenching, and tempering. By controlling the heating temperature and cooling rate, the structure and hardness of bearing steel can be adjusted.
7. Processing and Forming: After heat treatment, bearing steel billets are processed through processes such as turning, grinding, and boring to ultimately form various parts of bearings.
8. Surface treatment: Finally, the bearing parts undergo surface treatment, including grinding, polishing, coating, etc., to improve their surface quality and wear resistance.
The above is the general production process of bearing steel, and the specific production process may vary depending on different factories and requirements. Strictly control the quality of each link throughout the entire production process to ensure that bearing steel has good performance and reliability.