Manufactured by CHG Bearing, the NNU 4984 BK/SPW33 is a precision Super-Precision Cylindrical Roller Bearings. Key dimensional parameters include a 420 mm bore diameter, a 560 mm outer diameter, and a 140 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 4984 BK/SPW33 - Super-Precision Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU 4984 BK/SPW33 |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Super-precision Cylindrical Roller Bearing |
| Design Type | Tapered Bore 1:12 |
| 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) | 420 mm |
| Width (B) | 140 mm |
| Outer Diameter (D) | 560 mm |
| Minimum Chamfer Dimension rmin | 3 mm |
| Inner Ring Chamfer | 4 mm |
| Outer Ring Chamfer | 4 mm |
| End-face Height Difference h | 5.5 mm |
| Outer-Ring Land Diameter (L2 / D1) | 510.5 mm |
| Inner Ring Raceway Diameter F | 466 mm |
| Shaft Shoulder Diameter dₐ, min. | 435 mm |
| Shaft Shoulder Diameter dₐ, max. – NNU Design | 461 mm |
| Housing Shoulder Diameter Dₐ, max. | 544 mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 1510 kN |
| Basic Static Load Rating C₀ (kN) | 4000 kN |
| Limiting Speed – Grease (r/min) | 1200 r/min |
| Limiting Speed – Oil-air (r/min) | 1400 r/min |
| Fatigue Load Limit Pᵤ (kN) | 335 kN |
| Material | |
| Lubrication Groove Width | 16.7 mm |
| Lubrication Holes (qty × Ø mm) | 9 |
| Weight (kg) | 94.5 kg |
| Radial Internal Clearance | C1 mm |
NNU 4984 BK/SPW33 560 mm 420 mm 140 mm Frequently Asked Questions about NNU 4984 BK/SPW33 Super-Precision Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
To match diverse operational dynamics, CHG Bearing supplies NNU 4984 BK/SPW33 with multiple cage configurations: high-strength pressed steel ribbon cages for standard duty, solid machined brass cages (M/CA) for heavy vibration and shock loads, or lightweight glass-fiber reinforced polyamide cages (TN9/TVP) for high acceleration and ultra-low noise.
Standard batches of CHG Bearing NNU 4984 BK/SPW33 conform strictly to ISO Class Normal (ABEC-1). For high-precision machine tool spindles, gearboxes, or robotics requiring tighter runouts, CHG Bearing can provide custom batches graded to ISO Class 6 (P6/ABEC-3) or ISO Class 5 (P5/ABEC-5) with 100% micrometer verification.
In its sealed configuration (Open Type), CHG Bearing pre-charges NNU 4984 BK/SPW33 with premium wide-temperature lithium-complex or polyurea grease, calibrated to a 30%–35% cavity volume ratio. For open-type variants, synthetic PAO or refined mineral lubricating oils with appropriate EP (Extreme Pressure) additives should be circulated.
Following standard ISO 281 fatigue calculation guidelines, the nominal rating life (L10) of CHG Bearing NNU 4984 BK/SPW33 correlates its dynamic capacity (standard dynamic) with equivalent dynamic loads. In controlled industrial settings with proper contamination-free filtration, field data confirms continuous operational longevity exceeding 20,000 to 50,000 service hours.
