Manufactured by CHG Bearing, the NNU 4956 B/SPW33 is a precision Super-Precision Cylindrical Roller Bearings. Key dimensional parameters include a 280 mm bore diameter, a 380 mm outer diameter, and a 100 mm overall width. This component is designed to meet standard load requirements and ensure consistent operational performance. For comprehensive technical evaluation, please explore the detailed specifications, dimensional data, product images, and CAD drawings provided below. A complete PDF data sheet is also readily available for direct download to support your engineering and procurement needs.
NNU 4956 B/SPW33 - Super-Precision Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU 4956 B/SPW33 |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Super-precision Cylindrical Roller Bearing |
| Design Type | Cylindrical Bore |
| Structure (Drawing Reference) | Complete Bearing |
| Number of Rows | 2 |
| Ring Type | None |
| Design | NNU Design |
| Tolerance Class | SP |
| Bearing Material | Bearing Steel |
| Coating | None |
| Sealing | None |
| Lubricant | None |
| Features | Annular Lubrication Groove and Lubrication Holes |
| Number of Flanges – Outer Ring | 3 |
| Number of Ribs – Inner Ring | 0 |
| Dimensions | |
| Bore Diameter (d) | 280 mm |
| Width (B) | 100 mm |
| Outer Diameter (D) | 380 mm |
| Minimum Chamfer Dimension rmin | 2 mm |
| Inner Ring Chamfer | 2.1 mm |
| Outer Ring Chamfer | 2.1 mm |
| End-face Height Difference h | 4.5 mm |
| Outer-Ring Land Diameter (L2 / D1) | 345.6 mm |
| Inner Ring Raceway Diameter F | 312 mm |
| Shaft Shoulder Diameter dₐ, min. | 291 mm |
| Shaft Shoulder Diameter dₐ, max. – NNU Design | 308 mm |
| Shaft Shoulder Diameter dᵦ, min. – NNU Design | 316 mm |
| Housing Shoulder Diameter Dₐ, max. | 369 mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 765 kN |
| Basic Static Load Rating C₀ (kN) | 1800 kN |
| Limiting Speed – Grease (r/min) | 1900 r/min |
| Limiting Speed – Oil-air (r/min) | 2200 r/min |
| Reference Grease Quantity Gref (cm³) | 384 cm³ |
| Fatigue Load Limit Pᵤ (kN) | 170 kN |
| Axial Static Stiffness – Guideline Value (N/µm) | 7260 N/µm |
| Material | |
| Lubrication Groove Width | 13.9 mm |
| Lubrication Holes (qty × Ø mm) | 3 |
| Weight (kg) | 32.8 kg |
| Radial Internal Clearance | C1 mm |
| Internal Design & Weight | |
| Cage Type | Machined Metal Cage |
| Mounting Dimensions | |
| Lubrication Port Thread / Size Φ1 | 313.5 |
NNU 4956 B/SPW33 380 mm 280 mm 100 mm Frequently Asked Questions about NNU 4956 B/SPW33 Super-Precision Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Yes, CHG Bearing works closely with industrial OEMs and brand distributors. We offer turnkey custom engineering for NNU 4956 B/SPW33, including laser-etched customer logos, custom internal radial clearances, specialized grease formulations, and bespoke protective packaging.
The CHG Bearing NNU 4956 B/SPW33 is rated for limiting speeds up to standard rated RPM under forced oil-mist or circulating oil lubrication regimes. When lubricated with factory-filled synthetic high-speed grease, safe continuous velocity is maintained at approximately 75% to 85% of the maximum nominal limit, preventing thermal runaway.
To extend the trouble-free lifespan of CHG Bearing NNU 4956 B/SPW33, preventive maintenance routines should monitor operating housing temperature (normally maintaining below 70°C) and conduct regular vibration FFT analysis to identify early raceway micro-pitting before unexpected line halts occur.
To ensure optimum performance of CHG Bearing NNU 4956 B/SPW33 Super-Precision Cylindrical Roller Bearings under general rotational loads, our application engineers advise an inner-ring shaft tolerance of m5 or k5 for the 280 mm bore. For the 380 mm outer ring, an H7 or J7 housing bore fit is recommended to eliminate creep while accommodating normal thermal gradient expansion.
