Manufactured by CHG Bearing, the NNU4976/W33 is a precision Double Row Cylindrical Roller Bearings. Key dimensional parameters include a 380 mm bore diameter, a 520 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.

NNU4976/W33 - Double Row Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU4976/W33 |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Double Row Cylindrical Roller Bearing |
| Number of Rows | Double Row |
| Tolerance Class | P0 |
| Dimensions | |
| Bore Diameter (d) | 380 mm |
| Width (B) | 140 mm |
| Outer Diameter (D) | 520 mm |
| Bore Diameter Tolerance | -0.040 – 0 mm |
| Outside Diameter Tolerance | -0.050 – 0 mm |
| Width Tolerance | -0.40 – 0 mm |
| Enveloping Circle Diameter Fw | 426 mm |
| Inner Ring Chamfer | 4 min mm |
| Outer Ring Chamfer | 4 min mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 1720 kN |
| Basic Static Load Rating C0 (kN) | 4090 kN |
| Material | |
| Mass (kg) | 90.8 kg |
| Ring Material | Bearing Steel |
| Rolling Element Material | Bearing Steel |
| Cage Material | Brass |
| Lubrication Groove Width | 16.7 mm |
| Lubrication Holes (qty × Ø mm) | 3 × Ø9 |
NNU4976/W33 520 mm 380 mm 426 mm 140 mm Frequently Asked Questions about NNU4976/W33 Double Row Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Beyond standard alloy steel, CHG Bearing can customize the NNU4976/W33 Double Row Cylindrical Roller Bearings using AISI 440C stainless steel, black oxide coating, zinc-nickel plating, or hybrid ceramic (Si3N4) balls for applications involving chemical exposure, marine salt fog, or galvanic current hazards.
Quality starts with raw material selection: CHG Bearing crafts NNU4976/W33 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.
Every production batch of CHG Bearing NNU4976/W33 Double Row 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.
Yes, 100% of NNU4976/W33 Double Row Cylindrical Roller Bearings leaving CHG Bearing production lines are subjected to multi-frequency Anderometer sound testing. All units satisfy baseline Z1V1 levels, with dedicated quiet-running electric motor quality (EMQ) lots certified to Z2V2 and Z3V3 standards for silent machinery integration.
