The ferrule and rolling body of the rolling bearing are […]
The ferrule and rolling body of the rolling bearing are subjected to high touch pressure while being repetitively touched while sliding. The retainer slides and touches the ferrule and the rolling body on either side or one of its sides, and the pulling force and shortening force are applied on the other side. Therefore, the material, function, and important request of the bearing ring, the rolling body and the cage are as follows. The function requested by the ferrule and the tumbling body material: tumbling fatigue strength, high hardness, high wear resistance and high wear resistance
The function requested by the cage material: good standard stability, high mechanical strength
In addition, good workability is also required. Depending on the application, it also implores good impact resistance, heat resistance, and erosion resistance.
Material of ferrule and tumbler: High-carbon chromium bearing steel is usually used for ferrule and tumbler. Most bearings use SUJ2 in JIS steel grades. Large bearings use SUJ3. The chemical composition of SUJ2 has been standardized as a material for sliding bearings in countries all over the world. For example: it is the same kind of steel as AISL52100 (USA), DIN100Cr6 (West Germany), BS535A99 (UK), etc.
In the case of further impact resistance, chromium steel, chromium-molybdenum steel, nickel-chromium-molybdenum steel, and carburizing quenching are used as bearing materials, so that the steel has a softening layer from the surface to the appropriate depth. The carburized bearing with proper softening depth, fine arrangement, suitable hardness surface and core hardness has better impact resistance than bearings using bearing steel, and the chemical composition of a single carburized bearing steel.
NSK has implemented vacuum degassing treatment, so the materials used have high cleanliness, less oxygen content, and good quality. In turn, proper heat treatment was adopted to significantly improve the rolling fatigue life of the bearing.
In addition to the above-mentioned steel types, high-speed steel with excellent heat resistance and stainless steel with good corrosion resistance are used according to exceptional applications.
Cage material: the material of stamping cage is made of low carbon steel. Depending on the application, brass plates and stainless steel plates are also used. The material of the cut cage is made of high-strength brass and carbon steel, and differentiated resin is also used.