The majority of pressed sheet steel cages are made from continuously hot-rolled low carbon sheet steel according to (DIN) EN 10111:1998. These lightweight cages have relatively high strength and can be surface treated to further reduce friction and wear.
Pressed cages normally used in stainless steel bearings are made from stainless steel X5CrNi18-10 according to EN 10088-1:1995.
Machined steel cages
Machined steel cages are normally made of non-alloyed structural steel of type S355GT (St 52) according to 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-size bearings or in applications where there is a danger that season cracking, caused by a chemical reaction, may occur if a brass cage were used. Steel cages can be used at operating temperatures up to 300 ºC. 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.
Sheet brass cages
Pressed sheet brass cages are used for some small and medium-sized bearings. The brass used for these cages conforms to EN 1652:1997. In applications such as compressors for refrigeration using ammonia, season cracking in sheet brass might occur, therefore machined brass or steel cages should be used instead.
Machined brass cages
Most brass cages are machined from a CW612N cast or wrought brass according to EN 1652:1997. They are unaffected by most common bearing lubricants, including synthetic oils and greases, and can be cleaned using normal organic solvents. Brass cages should not be used at temperatures in excess of 250 ºC.