Brass Materials and their Application for Cages in Rolling Bearings

摘要

The use of brass in form of cages in rolling bearing applications is a compromise between four main variables: machinability, material cost, wear properties and mechanical strength. Due to design and performance requirements the emphasis is moving from production and base costs of the cage to reliable performance of the total bearing at its maximum rating. In this, the tribological properties of the cage is assuming a greater role and the performance of the rolling element/cage and the cage/land contact at bearing ring shoulders under grease and oil lubrication is of prime importance. Cages made of special brass grades or bronze are used in applications with high shock loads and vibrations such as in railway vehicles or in the cement and mining industry, while cages made from special nickel-copper alloys show excellent strength at high temperatures, anti-corrosion behaviour under atmospheric and salt water environment and resistance against a variety of acid and alkaline dissolutions. In order to face the challenges of high demanding applications further improved bearing systems are needed and one part of it is the cage inside where only a combination of optimised design and high strength materials can do the job.