Manufactured by CHG Bearing, the NNU4976/W33P5 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/W33P5 - Double Row Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU4976/W33P5 |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Double Row Cylindrical Roller Bearing |
| Number of Rows | Double Row |
| Tolerance Class | P5 |
| Dimensions | |
| Bore Diameter (d) | 380 mm |
| Width (B) | 140 mm |
| Outer Diameter (D) | 520 mm |
| Bore Diameter Tolerance | -0.023 – 0 mm |
| Outside Diameter Tolerance | -0.028 – 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/W33P5 520 mm 380 mm 426 mm 140 mm Frequently Asked Questions about NNU4976/W33P5 Double Row Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
When fitting NNU4976/W33P5 over a 380 mm shaft, CHG Bearing strictly recommends uniform induction heating (controlled between 90°C and 110°C) or precision hydraulic press sleeves. Under no circumstances should direct impact blows be struck against the rings or cage, as shock loads cause brinelling indents and premature spalling.
Standard batches of CHG Bearing NNU4976/W33P5 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.
To ensure optimum performance of CHG Bearing NNU4976/W33P5 Double Row Cylindrical Roller Bearings under general rotational loads, our application engineers advise an inner-ring shaft tolerance of m5 or k5 for the 380 mm bore. For the 520 mm outer ring, an H7 or J7 housing bore fit is recommended to eliminate creep while accommodating normal thermal gradient expansion.
Model NNU4976/W33P5 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 380 mm) and steep thermal gradients between inner and outer rings.
