NTN NU2211EAT2X CYLINDRICAL ROLLER BEARING

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

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

Explanation :
- 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 bounding dimensions are retained, but internal specifications are optimized (increased roller diameter, length and number of rollers).
- 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, which simplifies mounting and disassembly. Axial displacement takes place by sliding on the seating surfaces, making these bearings a natural solution for floating bearings.

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

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

Maintenance :
Open bearing: lubrication (grease or oil) must be adapted to service conditions. The ULTAGE™ series benefits from extended relubrication intervals. Shaft/bore mounting tolerances must comply with NTN recommendations to maintain residual clearance within the allowable range. In operation, monitor temperature, vibrations and noise. The allowable misalignment is 1/500 mm/mm.

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

Applications :
These NTN bearings are used as a floating bearing, combined with a fixed bearing (type NJ or NUP) to form a complete arrangement. They are suitable for industrial drives, long-shaft gear reducers, gearboxes, electric motors and pump-motor 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 suitable for equipment with variable loads or frequent starts.