Manufactured by CHG Bearing, the NNU 4924 B/SPW33 is a precision Super-Precision Cylindrical Roller Bearings. Key dimensional parameters include a 120 mm bore diameter, a 165 mm outer diameter, and a 45 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 4924 B/SPW33 - Super-Precision Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU 4924 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) | 120 mm |
| Width (B) | 45 mm |
| Outer Diameter (D) | 165 mm |
| Minimum Chamfer Dimension rmin | 1 mm |
| Inner Ring Chamfer | 1.1 mm |
| Outer Ring Chamfer | 1.1 mm |
| End-face Height Difference h | 1.1 mm |
| Outer-Ring Land Diameter (L2 / D1) | 150.5 mm |
| Inner Ring Raceway Diameter F | 134.5 mm |
| Shaft Shoulder Diameter dₐ, min. | 126 mm |
| Shaft Shoulder Diameter dₐ, max. – NNU Design | 133 mm |
| Shaft Shoulder Diameter dᵦ, min. – NNU Design | 137 mm |
| Housing Shoulder Diameter Dₐ, max. | 158.5 mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 176 kN |
| Basic Static Load Rating C₀ (kN) | 340 kN |
| Limiting Speed – Grease (r/min) | 4800 r/min |
| Limiting Speed – Oil-air (r/min) | 5300 r/min |
| Reference Grease Quantity Gref (cm³) | 27 cm³ |
| Fatigue Load Limit Pᵤ (kN) | 37.5 kN |
| Axial Static Stiffness – Guideline Value (N/µm) | 3140 N/µm |
| Material | |
| Lubrication Groove Width | 5.5 mm |
| Lubrication Holes (qty × Ø mm) | 3 |
| Weight (kg) | 2.91 kg |
| Radial Internal Clearance | C1 mm |
| Internal Design & Weight | |
| Cage Type | Machined Metal Cage |
| Mounting Dimensions | |
| Lubrication Port Thread / Size Φ1 | 135.8 |
NNU 4924 B/SPW33 165 mm 120 mm 45 mm Frequently Asked Questions about NNU 4924 B/SPW33 Super-Precision Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Quality starts with raw material selection: CHG Bearing crafts NNU 4924 B/SPW33 inner and outer rings from high-purity High-Quality Chrome Steel (GCr15/100Cr6). Our raw billets undergo vacuum degassing and secondary ESR (electroslag remelting) processes to drastically eliminate non-metallic sulfide and oxide inclusions, elevating subsurface contact fatigue resistance.
To ensure optimum performance of CHG Bearing NNU 4924 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 120 mm bore. For the 165 mm outer ring, an H7 or J7 housing bore fit is recommended to eliminate creep while accommodating normal thermal gradient expansion.
In its sealed configuration (Open Type), CHG Bearing pre-charges NNU 4924 B/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.
As standard production, CHG Bearing subjects NNU 4924 B/SPW33 to precision bainite or martensite quenching, offering dimensional stability up to 120°C (248°F). For high-heat processing equipment, CHG Bearing also supplies custom S0 (150°C), S1 (200°C), or S2 (250°C) stabilization heat treatments upon request to prevent residual austenite transformation.
