Manufactured by CHG Bearing, the NNU 4936 BK/SPW33 is a precision Super-Precision Cylindrical Roller Bearings. Key dimensional parameters include a 180 mm bore diameter, a 250 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.
NNU 4936 BK/SPW33 - Super-Precision Cylindrical Roller Bearings
Technical Specifications
| Overview | |
|---|---|
| Part Number | NNU 4936 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) | 180 mm |
| Width (B) | 69 mm |
| Outer Diameter (D) | 250 mm |
| Minimum Chamfer Dimension rmin | 2 mm |
| Inner Ring Chamfer | 2 mm |
| Outer Ring Chamfer | 1 mm |
| End-face Height Difference h | 1.1 mm |
| Outer-Ring Land Diameter (L2 / D1) | 226.05 mm |
| Inner Ring Raceway Diameter F | 202 mm |
| Shaft Shoulder Diameter dₐ, min. | 190 mm |
| Shaft Shoulder Diameter dₐ, max. – NNU Design | 199 mm |
| Housing Shoulder Diameter Dₐ, max. | 240 mm |
| Performance | |
| Basic Dynamic Load Rating C (kN) | 402 kN |
| Basic Static Load Rating C₀ (kN) | 850 kN |
| Limiting Speed – Grease (r/min) | 3000 r/min |
| Limiting Speed – Oil-air (r/min) | 3400 r/min |
| Reference Grease Quantity Gref (cm³) | 81 cm³ |
| Fatigue Load Limit Pᵤ (kN) | 88 kN |
| Axial Static Stiffness – Guideline Value (N/µm) | 5190 N/µm |
| Material | |
| Lubrication Groove Width | 8.3 mm |
| Lubrication Holes (qty × Ø mm) | 3 |
| Weight (kg) | 10.1 kg |
| Radial Internal Clearance | C1 mm |
| Internal Design & Weight | |
| Cage Type | Machined Metal Cage |
| Mounting Dimensions | |
| Lubrication Port Thread / Size Φ1 | 203.5 |
NNU 4936 BK/SPW33 250 mm 180 mm 69 mm Frequently Asked Questions about NNU 4936 BK/SPW33 Super-Precision Cylindrical Roller Bearings
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
Every production batch of CHG Bearing NNU 4936 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.
As a primary manufacturer, CHG Bearing supports both trial batch evaluations and container-load supply for NNU 4936 BK/SPW33. Standard catalog sizes are stocked for rapid 3–7 day dispatch, while high-volume OEM production runs typically dispatch within 30–45 days.
In its sealed configuration (Open Type), CHG Bearing pre-charges NNU 4936 BK/SPW33 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.
To ensure optimum performance of CHG Bearing NNU 4936 BK/SPW33 Super-Precision Cylindrical Roller Bearings under general rotational loads, our application engineers advise an inner-ring shaft tolerance of m5 or k5 for the 180 mm bore. For the 250 mm outer ring, an H7 or J7 housing bore fit is recommended to eliminate creep while accommodating normal thermal gradient expansion.
