How is the heat treatment process used to manufacture INDUSTRIAL MOTOR BEARING?

Heat treatment is a process that improves the internal structure and performance of metal materials through heating, insulation and cooling. For industrial motor bearings, heat treatment can significantly improve the hardness, wear resistance, fatigue resistance and use of the bearings. life. By optimizing the heat treatment process, the best overall performance matching the bearing usage conditions and failure modes can be obtained.

The heat treatment process of industrial motor bearings usually includes several key steps such as preheating, quenching, tempering and cooling.
Preheating: Before formal quenching, bearing parts need to be preheated, that is, normalized or spheroidized annealing. The main purpose of normalizing is to eliminate residual stress in the raw material, refine the grains, and improve the processing performance of the material, while spheroidizing annealing is to obtain a uniform spherical carbide structure to prepare for subsequent quenching. These pretreatment processes are usually carried out in box furnaces or pit furnaces by controlling the heating temperature and holding time.
Quenching: Quenching is the core link of heat treatment. Through rapid cooling, bearing parts can obtain high hardness and high strength. For industrial motor bearings, commonly used quenching media include oil, water or salt bath. During the quenching process, the parts are heated above the critical temperature and then quickly immersed in the quenching medium to achieve rapid cooling. Quenching temperature, holding time and cooling rate are key factors affecting quenching quality and need to be adjusted according to the specific material and part size.
Tempering: Although the quenched bearing parts have high hardness, they are also relatively brittle and prone to cracks. They need to be tempered to eliminate internal stress and improve toughness and stability. Tempering is usually carried out in a resistance furnace, oil bath or nitrate salt, and is achieved by controlling the heating temperature and holding time. The tempered bearing parts not only maintain high hardness, but also have good toughness and wear resistance.
Cooling and subsequent treatment: Tempered bearing parts need to be naturally cooled to room temperature. For some precision bearings, cryogenic treatment is also required to further reduce the amount of retained austenite and improve dimensional stability and hardness. Bearing parts need to be cleaned, oiled or greased after heat treatment to protect the surface of the parts and prevent corrosion.

During the heat treatment process, parameters such as heating temperature, holding time, and cooling rate need to be strictly controlled to obtain ideal tissue structure and performance. For different types of bearing parts and usage conditions, appropriate heat treatment processes and parameters need to be selected. With the increasing awareness of energy conservation and environmental protection, the efficiency and energy saving of heat treatment processes have also become a research hotspot. For example, measures such as adopting rapid heating and cooling technology, optimizing furnace structure, and developing new energy-saving materials can reduce energy consumption and improve production efficiency.