Guidelines for Material Selection of Bearing Retainers: Adaptation Strategies for Working Conditions from Metal to Engineering Plastics

In the design of rolling bearings, although the cage does not directly bear the load, it plays a key role in the stability, service life, and applicable working conditions of operation. The selection of materials should comprehensively consider factors such as rotational speed, temperature, corrosive environment, and safety requirements

The common materials and their characteristics are as follows:

Brass solid retainer (code M): High mechanical strength, wear-resistant, suitable for most conventional working conditions, with almost no usage restrictions. However, it should be noted that stress corrosion cracking is prone to occur in environments containing ammonia, and its use should be avoided. In addition, due to cost and processing reasons, small bearings usually do not adopt this type of structure.

Engineering plastic retaining frame (such as TN type, often glass fiber reinforced nylon): lightweight, low friction, especially suitable for high-speed operation. Its failure mode has a "gradual" nature - the temperature will slowly increase with performance degradation, making it easy to warn in advance. However, due to non sudden failure, it may pose safety hazards in scenarios such as mines where there is a risk of explosion, so it is not recommended to use it. The general working temperature range is -40 ℃ to 120 ℃.

Steel or ductile iron cage (code F): sturdy structure, low cost, suitable for most universal bearings. However, it is less commonly used in large bearings (with an outer diameter exceeding 400mm), mainly due to considerations of weight and dynamic balance.

Selection reference basis:

Taking deep groove ball bearings as an example, when the outer diameter D is ≤ 400mm, stamped steel plates or brass plate retainers are often used; For large-sized bearings with D>400mm, brass solid retainers are preferred to ensure structural rigidity and operational reliability.

In summary, the selection of retaining frame materials is not "the more expensive the better", but should closely follow the actual operating conditions and achieve the optimal balance between safety, lifespan, and cost.