NTN NU209EAT2X CYLINDRICAL ROLLER BEARING

Suited to high radial loads and use as a floating or fixed bearing, cylindrical roller bearings feature 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.

The 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 offers increased load capacity within the same envelope as standard series, with extended maintenance intervals as a result.

Decoding:
- 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 envelope dimensions retained, but internal specifications optimized (increased roller diameter, length and number).
- T2X: glass-fiber-reinforced polyamide cage.

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 disassembly. Axial displacement occurs by sliding on the seats, making these bearings a natural solution for floating bearings.

The ULTAGE™ series retains the envelope dimensions of standard bearings while incorporating larger-diameter rollers in greater numbers. The profile of the roller generatrix is optimized to limit stress concentrations at the ends of the contact. These internal improvements result in increased dynamic load capacity and an allowable speed improved by 20% compared with 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 glass-fiber-reinforced polyamide 66 cage offers good mechanical strength, heat resistance and low wear. This material also provides 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 re-lubrication intervals. Shaft/bore mounting tolerances must comply with NTN recommendations to maintain the residual clearance within the acceptable range. In operation, monitor temperature, vibrations and noise. The allowable misalignment is 1/500 mm/mm.

Key benefits:
- Increased radial load capacity within the same envelope, without modifying existing bore dimensions.
- Separable inner ring, facilitating mounting and replacement without full shaft removal.
- Free axial displacement absorbing thermal expansion 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 floating bearings, paired 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 units, wherever the shaft is subject to thermal expansion or axial displacement. The robustness of the ULTAGE™ profile and the polyamide cage also makes them relevant for equipment with variable loads or frequent starts.