SKF polymer ball bearings can be manufactured from a variety of materials and material combinations. The selected materials depend on the application conditions. Polymer thrust ball bearings are available in the four standard material combinations listed in table 1. A four-digit combination designation suffix (→ Designation system) identifies the selected materials.
Most polymers can resist the damaging effects of commonly used chemicals.
Polypropylene (PP) resists acids, alkalis, salts and salt solutions, alcohols, oils, greases, waxes and many solvents. However, exposure to aromatic compounds and halogenated hydrocarbons cause the material to swell. PP also does not resist strong oxidizing media like nitric acid, chromates or halogens.
Polyoxymethylene (POM) resists weak acids, weak and strong alkalis and organic solvents as well as gasoline, benzene, oils and alcohols.
Polyamide 66 (PA66) resists almost all organic solvents as well as some weak acids and alkalis.
Table 2 provides an overview of the chemical resistance of available materials to common substances.
For additional information, refer to Factors influencing bearing performance.