NNU 4921 B/SPW33
Super-precision double row cylindrical roller bearing with lubrication feature
Super-precision double row cylindrical roller bearings in the NNU 49 series are designed to accommodate heavy radial loads and high speeds, while providing a high degree of stiffness.
Having three flanges on the outer ring and no flanges on the inner ring, the bearings can accommodate axial displacement in both directions. The separable design simplifies mounting and dismounting, particularly when load conditions require both rings to have an interference fit.
- High radial load carrying capacity
- Very high rigidity and high running accuracy
- Minimize noise, vibration and heat generation
- Accommodate axial displacement in both directions
- Lubrication feature
- Thin section enabling compact application design
Dimensions
| d |
105 mm
|
Bore diameter |
| D |
145 mm
|
Outside diameter |
| B |
40 mm
|
Width |
| D1 |
130.8 mm
|
Shoulder diameter outer ring (NNU design) |
| F |
118 mm
|
Raceway diameter inner ring (NNU design) |
| b |
5.5 mm
|
Width annular lubrication groove at outer ring |
| K |
3 mm
|
Diameter lubrication hole (outer ring) |
| r1,2 |
min.1.1 mm
|
Chamfer dimension outer ring |
| r3,4 |
min.1.1 mm
|
Chamfer dimension inner ring (bearing with tapered bore) |
| s |
max.1.1 mm
|
Permissible axial displacement from the normal position of one bearing ring relative to the other (all) |
Abutment dimensions
| da |
min.111 mm
|
Abutment diameter shaft |
| da |
max.116 mm
|
Abutment diameter shaft (NNU design) |
| db |
min.121 mm
|
Abutment diameter shaft (NNU design; not for tapered bore) |
| Da |
max.138.5 mm
|
Abutment diameter housing |
| ra |
max.1 mm
|
Fillet radius |
| dn |
119 mm
|
Oil nozzle position (not for variants with TNHA cage) |
Calculation data
| Basic dynamic load rating |
C |
130 kN
|
| Basic static load rating |
C0 |
260 kN
|
| Fatigue load limit |
Pu |
30 kN
|
| Attainable speed for grease lubrication |
|
5 300 r/min
|
| Attainable speed for oil-air lubrication |
|
6 000 r/min
|
| Reference grease quantity |
Gref |
15 cm³
|
| Static radial stiffness (guideline value) |
|
3 040 N/µm
|
