Manufactured by CHG Bearing, the NNU4938 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.
NNU4938 - Double Row Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU4938 |
| 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 | -0.030 – 0 mm |
| Outside Diameter Tolerance | -0.035 – 0 mm |
| Width Tolerance | -0.35 – 0 mm |
| Enveloping Circle Diameter Fw | 210 mm |
| Inner Ring Chamfer | 2 min mm |
| Outer Ring Chamfer | 2 min mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 465 kN |
| Basic Static Load Rating C0 (kN) | 996 kN |
| Material | |
| Mass (kg) | 11 kg |
| Ring Material | Bearing Steel |
| Rolling Element Material | Bearing Steel |
| Cage Material | Brass |
NNU4938 260 mm 190 mm 210 mm 69 mm Frequently Asked Questions about NNU4938 Double Row Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Every production batch of CHG Bearing NNU4938 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.
Quality starts with raw material selection: CHG Bearing crafts NNU4938 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.
When fitting NNU4938 over a 190 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.
As standard production, CHG Bearing subjects NNU4938 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.
