Machine Design

Electrically Insulated Rolling Bearings

The SQ77 Series of rolling bearings feature built-in electrical insulation for protection against current discharge and the resulting electrical corrosion. Three versions are available: the SQ77 with an oxide ceramic insulation layer on the outer ring; the SQ77E with an insulation layer on the inner ring; and the SQ77B hybrid bearings, which feature ceramic rolling elements with theoretically infinite insulation resistance.

The SQ77 and SQ77E ceramic insulation is applied through plasma-spraying and has a 1,000 Vac/Vdc dielectric strength. The bearings with outer ring insulation are available as cylindrical roller bearings or deep-groove ball bearings in various designs, dimension series and radial clearance classes.

NKE Austria GmbH, 20 Barney Rd., Box 5255, Clifton Park, NY 12065, (518) 371-5759,

© 2011 Penton Media, Inc.

TAGS: Products
Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.