NTN NU214EAT2X CYLINDRICAL ROLLER BEARING

Suitable for high radial loads and for use in free or fixed bearing arrangements, cylindrical roller bearings offer low friction and good stiffness. They are available in a wide range of models and variants addressing specific conditions: heat, axial displacement, operating noise, speed, capacity, etc.

NTN cylindrical roller bearings of the ULTAGE™ series provide a benchmark solution for applications with high radial loads and sustained rotational speeds. The optimized internal design of this range offers increased load capacity within the same envelope as standard series, with extended maintenance intervals as a result.

Breakdown :
- NU: single-row bearing with two shoulders on the outer ring and none on the inner ring; separable inner ring.
- EA: designates NTN’s ULTAGE™ series; standard limiting dimensions are retained, but internal specifications are optimized (increased roller diameter, length and number).
- T2X: cage in glass-fiber-reinforced polyamide.

Features :
These NU-type bearings are built around an outer ring with two shoulders and no shoulder on the inner ring. This configuration allows the outer-ring–rollers–cage assembly to be separated from the inner ring, simplifying mounting and dismounting. Axial displacement occurs by sliding on the seating surfaces, making these bearings a natural solution for free (floating) bearings.

The ULTAGE™ series retains the external dimensions of standard bearings while incorporating larger-diameter rollers in greater numbers. The roller generatrix profile is optimized to limit stress concentrations at the ends of the contact. These internal developments result in increased dynamic load capacity and an allowable speed improved by 20% compared with the standard when lubricated with oil. ULTAGE™ rings are not interchangeable with those of standard series due to the different inscribed circle diameter.

The cage in polyamide 66 reinforced with glass fibres exhibits good mechanical strength, heat resistance and low wear. This material also provides some flexibility during mounting, particularly useful on constrained geometries.

Maintenance :
Open bearing: lubrication (grease or oil) must be adapted to service conditions. The ULTAGE™ series benefits from extended re-greasing intervals. Shaft/housing fit tolerances must follow NTN recommendations to maintain the residual clearance within the permissible range. During operation, monitor temperature, vibrations and noise. The admissible misalignment is 1/500 mm/mm.

Key advantages :
- Increased radial load capacity in the same envelope, without modifying existing bore dimensions.
- Separable inner ring, facilitating mounting and replacement without full removal of the shaft.
- Free axial displacement accommodating thermal expansions without stressing other components of the assembly.
- Extended maintenance intervals thanks to the technical improvements of the ULTAGE™ series.

Applications :
These NTN bearings are used as free (floating) bearings, paired with a fixed bearing (type NJ or NUP) to form a complete arrangement. They are suited to industrial drives, long-shaft gear reducers, gearboxes, electric motors and pump-drive units, wherever the shaft is subject to thermal expansion or axial displacement. The robustness of the ULTAGE™ profile and the polyamide cage also make them relevant for equipment with variable loads or frequent starts.