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, on one side, slides and touches the sides of the ferrule and the tumbling body, or one of its sides, and is subject to tensile and contractive forces 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 generally 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 various countries around 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 to make the steel have a softening layer from the surface to the appropriate depth. Carburized bearings with appropriate softening depth, fine structure, suitable hardness surface and core hardness have better impact resistance than bearings using bearing steel, and the chemical composition of individual 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 is adopted to make the rolling fatigue life of the bearing significantly advance.
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.