Needle roller bearing ring and rolling body, a repeated under high contact pressure, side tumbling along with a sliding contact.
Retainer, one side with the ring and the two sides of the roll body, or its one side sliding contact, one side under tension and compression force.
Therefore, the bearing ring, rolling body and keep the frame material, performance, the main requirements are as follows.
Ring, rolling body material performance: the demand by the rolling fatigue strength high hardness, high resistance to friction consumption cage material performance: the demand by the dimension stability, good mechanical strength and good workability.
According to different purposes, and demand the impact resistance, heat resistance, good corrosion resistance.
Ring and roll body material: ring and roll body usually use high carbon chromium bearing steel.
Most of the bearing, using JIS SUJ2 steel grade.
Use SUJ3 large bearing.
The chemical composition of SUJ2, around the world, as a bearing material has been normalized.
For example: with AISL52100 (
The United States)
All belong to the same steel.
Need to further impact resistance, as a bearing material using nickel chrome steel, chrome molybdenum steel, chrome molybdenum steel, using carbon quenching, make the steel from the surface to the appropriate depth has a hardening layer.
With appropriate hardening depth, fine structure, suitable hardness of surface and the core hardness of carbon bearing, than using the bearing steel bearing has excellent resistance to impact, the average permeability coal bearing steel chemical composition.
Bearing adopted vacuum degassing treatment, so, the use of material purity degree is high, less oxygen content, good quality.
Then use the appropriate heat treatment, the bearing of the back obviously improve the weakness of life.
The steel grade, according to the special purpose, with excellent heat resistance of high speed steel, good corrosion resistance of stainless steel.
Cage materials: punch retainers material, the use of low carbon steel.
According to different purposes, also used brass, stainless steel plate.
Cutting system maintains a material, using brass, carbon steel, high strength, moreover also use synthetic resin.