Manufactured by CHG Bearing, the NNU 4924 BK/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 BK/SPW33 - Super-Precision Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU 4924 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) | 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 | 0.6 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 |
| 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) | 2.78 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 BK/SPW33 165 mm 120 mm 45 mm Frequently Asked Questions about NNU 4924 BK/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 4924 BK/SPW33, including laser-etched customer logos, custom internal radial clearances, specialized grease formulations, and bespoke protective packaging.
Model NNU 4924 BK/SPW33 is manufactured by CHG Bearing in standard Normal clearance (CN) for ambient temperature transmission, and C3 or C4 clearance for heavy duty applications. C3 clearance compensates for radial shrinkage caused by tight shaft press-fits (bore 120 mm) and steep thermal gradients between inner and outer rings.
Every production batch of CHG Bearing NNU 4924 BK/SPW33 Super-Precision Cylindrical Roller Bearings comes with complete traceability. Upon shipment, CHG Bearing can provide EN 10204 3.1 Material Test Reports (MTR), Certificates of Conformity (CoC), spectral chemical composition analysis, and dimensional inspection sheets.
The CHG Bearing NNU 4924 BK/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.
