FAG NJ2314-E-XL-M1-C4 0192256100040 CYLINDRICAL ROLLER BEARINGS

In applications with high temperatures and heavy loads, the choice of radial clearance is critical to the service life of the rolling bearing. This FAG version features a C4 radial clearance, specifically designed for large thermal expansions and very tight fits.

Explanation:
• NJ: Two flanges on the outer ring, one flange on the inner ring; axial guidance in one direction, floating bearing function in the opposite direction
• E: Increased radial load capacity through optimized internal geometry
• XL: FAG/INA X-life designation for longer service life and increased dynamic load ratings thanks to highly precise contact surfaces
• M1: Two-piece brass cage, roller-guided, for improved heat dissipation
• C4: Increased internal radial clearance above C3 level, suitable for high thermal expansions and very tight fits

Features:
The NJ series is based on a separable design: the inner ring can be mounted separately from the unit consisting of the outer ring and rolling elements. This allows both assemblies to be installed independently. The inner ring can be mounted on the shaft by itself initially, which is a significant advantage, particularly for shrink fits.
The E version uses an optimized internal geometry to distribute loads more evenly across the raceways. In combination with X-life technology, the bearings benefit from improved surface quality, which reduces friction, lowers heat generation, and places less stress on the lubricant. The result is higher dynamic basic load ratings and a longer nominal service life compared with earlier generations.
The C4 radial clearance is greater than the C3 clearance, which in turn is greater than the standard CN clearance. It was specifically developed for applications with large temperature differentials or heavy interference fits. This maintains sufficient allowance for deformation so that no harmful internal pre-load arises at operating temperature. The M1 brass cage complements this concept by providing stable roller guidance and efficient heat removal.

Maintenance:
For applications with C4 radial clearance, temperature monitoring has top priority. Unusually high temperatures can indicate excessive fit stresses, aged lubricants, or insufficient lubricant supply. Regular temperature checks help detect deviations early and prevent bearing damage.
The type and quantity of lubricant must be adapted to the actual operating temperatures. Although the M1 brass cage reduces internal bearing heat generation, it does not replace condition-based relubrication under real operating conditions.
In addition, vibration analysis and noise monitoring should be part of preventive maintenance. Even small changes in the vibration spectrum should be investigated. As this is an open rolling bearing, the bearing environment must be reliably protected from particles, dust, and moisture.

Strengths:
• C4 radial clearance prevents harmful internal pre-loads in tight fits and under large temperature fluctuations
• Higher load capacity allows accommodation of larger loads without changing the installation envelope
• Separable design reduces downtime during maintenance and overhaul
• M1 brass cage improves heat dissipation and is particularly suitable for high-temperature applications

Applications:
The C4 version is particularly suitable for heavy industry. Rolling mills, reheating furnaces, heat treatment plants, and high-pressure compressors are typical applications. In these installations, heating and cooling cycles alternate, subjecting the radial clearance to continuous thermal expansion. The C4 clearance compensates for these changes reliably without excessively stressing the bearing.
High-power gearboxes as well as drive and transmission shafts in high-temperature environments also benefit from this increased radial clearance, especially with very tight fit tolerances. Under these conditions, the E variant reduces stress on the raceways through optimized load distribution, while X-life quality enables longer service life and extended maintenance intervals.