Current discharge can be a problem with motors and machinery. One solution is to use insulated components, such as electrically insulated bearings. Compared to conventional bearings, electrically insulated bearings are more reliable in operation in electrical machinery due to their resistance to electrical corrosion. They also tend to be more cost-effective and reliable than shaft or housing insulation.
The SQ77 bearings have built-in electrical insulation for reliable protection against current discharge and the resulting electrical corrosion. They are available in three versions: the SQ77 series, with an oxide ceramic insulation layer on the outer ring; the SQ77E series with an insulation layer on the inner ring and the hybrid bearings of the SQ77B series which feature ceramic rolling elements with theoretically infinite insulation resistance. They have the same key dimensions and technical properties as conventional bearings and are therefore 100% interchangeable.
The SQ77 and SQ77E ceramic insulation is applied through plasma spraying and has a guaranteed dielectric strength of at least 1000 Vac or dc. The bearings with outer ring insulation are available as cylindrical roller bearings and as deep groove ball bearings in various designs, dimension series, and radial clearance classes.
NKE Austria GmbH
Filed Under: Bearings, Machine tool industry + subtractive manufacturing, Mechanical