NKE Electrically Insulated Deep Groove Ball Bearings
Find NKE Fersa insulated ball bearing alternatives by complete SQ77 or SQ77E designation. This product list contains 57 deep groove ball bearing configurations in the 62 and 63 series, with bore sizes from 50 mm to 160 mm, C3 or C4 clearance, and brass cages. The core SQ77 range uses an insulating ceramic coating on the outer ring, while selected SQ77E models in this list provide inner ring insulation options. These bearings are intended for VFD motors, railway traction motors, compressor motors, generators, and related electrical equipment. TFL can review an existing NKE bearing number, drawing, sample, or application and help source a specification-based alternative from qualified factory resources.
Superior Electrical Insulation to Prevent Bearing Failure
Seamless Interchangeability with NKE Bearings
Cost-Effective Alternative to Premium Brands
NKE Fersa Insulated Deep Groove Ball Bearing Cross-Reference Guide
This page focuses on alternatives for NKE Fersa SQ77 and SQ77E insulated deep groove ball bearing numbers. Use the product list to compare 62 and 63 series models by dimensions, insulation position, C3 or C4 clearance, brass cage, load rating, speed, and electrical requirements. If the original designation begins with NU, NJ, or NUP, use the NKE insulated cylindrical roller bearing range instead.
NKE Fersa and the SQ77 Insulated Bearing Range
NKE now operates under the NKE Fersa brand within Fersa. Its electrically insulated bearing technology uses a plasma-applied oxide ceramic layer to protect electrical machinery against damage caused by stray bearing currents.
NKE Fersa identifies its electrically insulated deep groove ball bearing range with the SQ77 suffix. The official core range includes 6212 to 6226 and 6312 to 6326 series bearings with brass cages and C3 or C4 radial internal clearance. This page also contains selected adjacent sizes and SQ77E configurations for specification-based cross-reference inquiries.
How to Read an NKE SQ77 Bearing Number
An NKE-style designation such as 6314-M-C3-SQ77 combines the basic deep groove ball bearing number with suffixes describing the cage, internal clearance, and insulation configuration. Every part of the designation should be checked before an alternative is approved.
| Designation Element | Example | Meaning for Selection |
|---|---|---|
| Basic bearing number | 6314 | Identifies the deep groove ball bearing series and principal dimensions |
| Cage suffix | M | Identifies the brass cage used throughout this product list |
| Internal clearance | C3 or C4 | Must suit the bearing fit, temperature, speed, and required running clearance |
| Insulation suffix | SQ77 | Identifies the electrically insulated outer ring configuration |
| Alternative insulation option | SQ77E | Identifies selected inner ring insulated configurations in this product list |
SQ77 and SQ77E Insulation Options
SQ77 models in this list use an oxide ceramic insulation coating on the outer ring. This configuration helps interrupt the electrical path between the bearing outer ring and housing. Selected SQ77E models use inner ring insulation and should be considered only after confirming the required current path and shaft interface.
Do not select SQ77 or SQ77E from the suffix alone. Confirm the coating position, required breakdown resistance, bore size, outside diameter, width, clearance, cage, load ratings, speed, and installation arrangement. Electrical values shown on individual product pages should be reviewed against the project specification before ordering.
NKE-Style Models Covered by This Product List
The list contains 57 configurations with bore diameters from 50 mm to 160 mm. Representative models include 6212-M-C3-SQ77, 6314-M-C3-SQ77, 6319-M-C4-SQ77, 6226-M-C3-SQ77, and 6328-M-C3-SQ77E.
Send the complete NKE bearing number rather than only the basic designation. For example, 6314, 6314-M-C3-SQ77, and 6314-M-C4-SQ77 describe different procurement requirements even when their principal dimensions are the same.
How to Check an NKE Insulated Ball Bearing Alternative
Begin with the complete part number shown on the existing bearing, motor drawing, maintenance record, or purchase history. First confirm the basic bearing dimensions, then compare the SQ77 or SQ77E suffix, coating position, C3 or C4 clearance, brass cage, load ratings, reference speed, and electrical requirements.
For an application-based review, provide the motor type, motor power, operating speed, VFD information, DE or NDE position, shaft and housing fits, load conditions, quantity, and any available drawing or sample. These details help distinguish a dimensional match from a suitable operating alternative.
Do Not Cross-Reference by Dimensions Alone
A bearing with the same bore, outside diameter, and width may still have a different clearance, cage, coating position, or electrical rating. The complete NKE-style designation and motor operating conditions should be reviewed before approving an alternative.
Applications for NKE-Style Insulated Ball Bearings
NKE-style SQ77 insulated deep groove ball bearing alternatives are considered for VFD motors, railway traction motors, compressor motors, generators, pumps, fans, wind-energy equipment, and other electrical machinery exposed to shaft voltage or circulating current.
Deep groove ball bearings are commonly used in locating and non-locating positions in small and medium motors and in locating positions in larger motors. They support relatively high speeds, radial loads, and moderate axial loads. Selection should account for motor power, VFD use, grounding, speed, fit, and DE or NDE installation position.
Send Us Your NKE SQ77 Bearing Number
Provide the complete bearing designation, motor power, VFD details, DE/NDE position, operating speed, quantity, drawing, or sample. We will review suitable insulated deep groove ball bearing alternatives.
NKE Insulated Ball Bearing or Cylindrical Roller Bearing?
This page covers NKE-style insulated deep groove ball bearings in the 62 and 63 series. If the original number begins with NU, NJ, or NUP, review the NKE-style insulated cylindrical roller bearing range. Deep groove ball bearings are generally selected for higher-speed positions requiring radial and moderate axial load support. Cylindrical roller bearings are more appropriate when higher radial load capacity, separable mounting, or axial displacement capability is required.Why Source NKE-Style Alternatives from TFL?
TFL / SDTFL Bearing is an independent bearing supplier and sourcing partner. We use the customer’s complete NKE-style designation, drawing, sample, or application requirements to identify suitable alternatives from qualified factory resources. Before shipment, we check the agreed model, quantity, visible condition, packaging, and basic quality requirements. Custom insulation specifications, OEM marking, neutral packaging, and customized packaging can be discussed according to the required model and order quantity. Buyers can also browse our complete electrically insulated deep groove ball bearing range.NKE and NKE Fersa are trademarks of their respective owner. TFL / SDTFL Bearing is an independent supplier and does not claim to be NKE Fersa or an authorized distributor. Brand-style numbers are used only to identify potential replacement, alternative, cross-reference, or interchange options. Final suitability must be confirmed against the complete designation and application requirements.
FREQUENTLY ASKED QUESTIONS
