Electrically Insulated Bearings

Optimum protection against bearing damage caused by the passage of currents

NKE electrically insulated rolling bearings reliably prevent current discharge.

NKE provides bearings with oxide ceramic insulating layers on the bearing ring. Applied with plasma technology, the insulation has a guaranteed breakdown resistance of at least 1000V AC or DC. Two variants are available:

SQ77: Insulation on the outer ring
SQ77E: Insulation on the inner ring

PDF Brochure

NKE General Catalogue

Typical applications

Traction motors of railway vehicles
Electric motors (AC/DC)
Generators (e.g. in wind turbine generators)

Product range

SQ77(insulated outer ring)

Cylindrical roller bearings
- Design variants: NJ, NU, NUP
- Dimension series: 210-230, 310-330
- Cages: brass and polyamide
- Radial clearance groups: C0, C3, C4
Deep groove ball bearings
- Dimension series: 6212-6226; 6312-6326
- Cages: brass
- Radial clearance groups: C3, C4
Other types and SQ77E (insulated inner ring) upon request

Advantages

Higher operational reliability through optimum protection against electrical corrosion
More economic than, for example, insulation on housings or shafts
Interchangeable: Same key dimensions and technical properties as conventional bearings
Coating resistant to damage if correctly handled