Machined metal cages
Machined steel cages
Machined steel cages are normally made of non-alloyed structural S355GT (St 52) type steel in accordance with EN 10 025:1990 + A:1993. To improve sliding and wear-resistance properties, some machined steel cages are surface treated.
Machined steel cages are used for large bearings or in applications where there is a danger that season cracking, caused by a chemical reaction, may occur if a brass cage is used. Steel cages can be used at operating temperatures up to 300 °C (570 °F). They are not affected by the mineral or synthetic oil-based lubricants normally used for rolling bearings, or by the organic solvents used to clean bearings.
Machined brass cages
Most brass cages are machined from a CW612N cast or wrought brass in accordance with EN 1652:1998. They are unaffected by most common bearing lubricants, including synthetic oils and greases, and can be cleaned using normal organic solvents. Brass cages can be used at operating temperatures up to 250 °C (480 °F).