SKF · super precision bearings
SKF NNU 4938 B/SPW33
Super-precision cylindrical roller bearings — manufacturer technical reference and quotation support in Saudi Arabia.
لطلب عرض سعر في السعودية، أرسل رقم القطعة أو المقاس والكمية والمدينة. يُرجى تأكيد التوافق والتوفر والسعر مع فريقنا.
| Bore diameter | 190 mm |
|---|---|
| Outside diameter | 260 mm |
| Width | 69 mm |
| Basic dynamic load rating | 402 kN |
| Basic static load rating | 880 kN |
| Attainable speed for grease lubrication | 2800 r/min |
| Attainable speed for oil-air lubrication | 3200 r/min |
| Bearing part | Complete bearing |
| Number of rows | 2 |
| Bore type | Cylindrical |
| Cage | Machined metal |
| Design | NNU |
| Number of flanges, outer ring | 3 |
| Number of flanges, inner ring | 0 |
| Loose flange | None |
| Radial internal clearance | C1 |
| Tolerance class | Class SP (SP) |
| Material, bearing | Bearing steel |
| Coating | Without |
| Sealing | Without |
| Lubricant | None |
| Relubrication feature | Annular groove and lubrication holes |
| Indicative carbon footprint for new product | 41.6 kg CO_2e |
| Product net weight | 11.2 kg |
| eClass code | 23-05-09-01 |
| UNSPSC code | 31171505 |
| Dimensions · Bore diameter · (d) | 190 mm |
| Dimensions · Outside diameter · (D) | 260 mm |
| Dimensions · Width · (B) | 69 mm |
| Dimensions · Shoulder diameter outer ring (NNU design) · (D_1) | 236 mm |
| Dimensions · Raceway diameter inner ring (NNU design) · (F) | 212 mm |
| Dimensions · Width annular lubrication groove at outer ring · (b) | 8.3 mm |
| Dimensions · Diameter lubrication hole (outer ring) · (K) | 3 mm |
| Dimensions · Chamfer dimension outer ring · (r_1,2) · min. | 2 mm |
| Dimensions · Chamfer dimension inner ring (bearing with tapered bore) · (r_3,4) · min. | 2 mm |
| Dimensions · Permissible axial displacement from the normal position of one bearing ring relative to the other (all) · (s) · max. | 1.1 mm |
| Abutment dimensions · Abutment diameter shaft · (d_a) · min. | 200 mm |
| Abutment dimensions · Abutment diameter shaft (NNU design) · (d_a) · max. | 209 mm |
| Abutment dimensions · Abutment diameter shaft (NNU design; not for tapered bore) · (d_b) · min. | 215 mm |
| Abutment dimensions · Abutment diameter housing · (D_a) · max. | 250 mm |
| Abutment dimensions · Fillet radius · (r_a) · max. | 2 mm |
| Abutment dimensions · Oil nozzle position (not for variants with TNHA cage) · (d_n) | 213 mm |
| Calculation data · Basic dynamic load rating · (C) | 402 kN |
| Calculation data · Basic static load rating · (C_0) | 880 kN |
| Calculation data · Fatigue load limit · (P_u) | 90 kN |
| Calculation data · Attainable speed for grease lubrication | 2800 r/min |
| Calculation data · Attainable speed for oil-air lubrication | 3200 r/min |
| Calculation data · Reference grease quantity · (G_ref) | 85 cm³ |
| Calculation data · Static radial stiffness (guideline value) | 5380 N/µm |
Family specifications and selection conditions
| Product description | 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. Also available on request with special sized bore and/or outside diameters, suitable for reworked shafts and housings. |
|---|---|
| Manufacturer features | 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 |
Manufacturer references
Follow the complete manufacturer documentation for application restrictions, materials, tolerances and installation requirements. Limits may not apply simultaneously. We do not publish inferred stock, pricing or ratings.