Overview
The SKF NJ 308 ECJ/C3 is a precision cylindrical roller bearing engineered for high radial load capacity combined with high-speed operation. This single-row bearing features brass sheet cage construction and C3 radial clearance, making it suitable for demanding industrial environments where reliability and performance are critical. NJ design bearings accommodate axial displacement in one direction through two integral flanges on the outer ring and one on the inner ring, with a separable design that facilitates mounting and enables component interchange.
Key Features
- High radial load accommodation in combination with high speeds
- C3 radial clearance for greater-than-normal internal spacing
- Separable inner ring design for easy assembly and maintenance
- Relubricatable design with steel cage material and RBEC 1 / ISO P0 precision class
- Reference speed rating of 8000 rpm
- Made in Germany, built to withstand industrial rigors
Technical Specifications
- Bore Diameter: 40 mm
- Outer Diameter: 90 mm
- Width: 23 mm
- Radial Clearance: C3
- Cage Material: Brass (sheet)
- Seal: Without seal
- Precision Class: RBEC 1 / ISO P0
- Number of Rows: Single
- Weight: 1.541 lbs (0.695 kg)
- Basic Static Load Rating: 78 kN
Typical Applications
The SKF NJ 308 ECJ/C3 is ideal for:
- Industrial gearboxes and transmission systems requiring high radial load support
- Conveyor systems and material handling equipment
- Pump and motor bearings in manufacturing facilities
- Machine tool spindles and rotating equipment
- Dynamic environments demanding high-speed rotation with low noise and vibration
Compatibility & Replacements
Compatible With
- Industrial equipment requiring 40mm bore cylindrical roller bearings
- Machinery designed for C3 clearance specifications
- High-speed rotating equipment up to 8000 rpm reference speed
- Systems requiring separable bearing designs for maintenance access
Replaces / Drop-In Replacement For
- Previous generations of SKF NJ 308 cylindrical roller bearings
- OEM specifications calling for 40x90x23mm single-row roller bearings with C3 clearance
- Comparable bearings from other manufacturers with identical bore, OD, and width dimensions
Works With
- Standard bearing lubrication systems and relubrication schedules
- Industrial bearing mounting fixtures and housings designed for 40mm bore diameter
- Precision alignment and fit systems requiring ISO P0 tolerance class
- Condition monitoring and vibration analysis equipment for predictive maintenance












