Manufactured by CHG Bearing, the NNU4938K/W33 is a precision Double Row Cylindrical Roller Bearings. Key dimensional parameters include a 190 mm bore diameter, a 260 mm outer diameter, and a 69 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.
NNU4938K/W33 - Double Row Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU4938K/W33 |
| Brand | CHG® |
| Characteristics | |
| Bearing Type | Double Row Cylindrical Roller Bearing |
| Number of Rows | Double Row |
| Tolerance Class | P0 |
| Dimensions | |
| Bore Diameter (d) | 190 mm |
| Width (B) | 69 mm |
| Outer Diameter (D) | 260 mm |
| Bore Diameter Tolerance | 0 – +0.050 mm |
| Outside Diameter Tolerance | -0.035 – 0 mm |
| Width Tolerance | -0.30 – 0 mm |
| Enveloping Circle Diameter Fw | 212 mm |
| Inner Ring Chamfer | 2 min mm |
| Outer Ring Chamfer | 2 min mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 439 kN |
| Basic Static Load Rating C0 (kN) | 918 kN |
| Material | |
| Mass (kg) | 10.9 kg |
| Ring Material | Bearing Steel |
| Rolling Element Material | Bearing Steel |
| Cage Material | Brass |
| Lubrication Groove Width | 9.5 mm |
| Lubrication Holes (qty × Ø mm) | 3 × Ø5 |
NNU4938K/W33 260 mm 190 mm 212 mm 69 mm Frequently Asked Questions about NNU4938K/W33 Double Row Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Standard batches of CHG Bearing NNU4938K/W33 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 NNU4938K/W33 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.
Absolutely. The CHG Bearing NNU4938K/W33 Double Row Cylindrical Roller Bearings is a 1:1 direct interchange for renowned brands, matching part numbers: SKF NNU4938K/W33, FAG NNU4938K/W33, NSK NNU4938K/W33. It shares identical envelope boundary dimensions, load capacities, and shaft fits, allowing instant drop-in replacement without retrofitting your machinery.
Following standard ISO 281 fatigue calculation guidelines, the nominal rating life (L10) of CHG Bearing NNU4938K/W33 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.
