Manufactured by CHG Bearing, the 45*78.1-1 is a precision Tapered Rollers. Key dimensional parameters include a mm bore diameter, a mm outer diameter, and a 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.

45*78.1-1 - Tapered Rollers
Technical Specifications
| Overview | |
|---|---|
| Part Number | 45*78.1-1 |
| Brand | CHG® |
| Product Type | Tapered Roller |
| Taper Angle | 42' |
| Dimensions | |
| Roller Length, Lw | 78.1 mm |
| Center Recess Diameter | 24 mm |
| Through-hole Diameter | - mm |
| Center Recess Depth | 1.5 mm |
| Large-end Diameter, Dw | 45 mm |
| Spherical End Radius, SR | 1749 mm |
| Through-hole Chamfer | - mm |
| Large-end Diameter Tolerance | -0.012 to +0.02 mm |
| Through-hole Coaxiality | - mm |
| Rolling Surface Roughness, Ra (µm) | 0.2 |
| Axial Chamfer — Large End | 1.5 mm |
| Axial Chamfer Tolerance — Large End | -0.2 to +0.2 mm |
| Radial Chamfer — Large End | 1.5 mm |
| Radial Chamfer Tolerance — Large End | -0.2 to +0.2 mm |
| Axial Chamfer — Small End | 1.5 mm |
| Axial Chamfer Tolerance — Small End | -0.2 to +0.2 mm |
| Radial Chamfer — Small End | 1.5 mm |
| Radial Chamfer Tolerance — Small End | -0.2 to +0.2 mm |
| Performance | |
| Spherical End Surface Roughness, Ra (µm) | 0.4 µm |
| Dimensional & Geometrical Accuracy | |
| Roller Length Tolerance | -0.4 to 0 mm |
| End-face Runout | - mm |
| Diameter Variation Between Ends | ±0.003 mm |
| Roundness | 0.003 mm |
| Ovality | 0.003 mm |
45*78.1-1 45 mm 78.1 mm 1749 mm Frequently Asked Questions about 45*78.1-1 Tapered Rollers
Find key technical answers regarding dimensions, specifications, and replacement options for this model.
In its sealed configuration (Open Type), CHG Bearing pre-charges 45*78.1-1 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.
Standard batches of CHG Bearing 45*78.1-1 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.
The CHG Bearing 45*78.1-1 is rated for limiting speeds up to standard rated RPM under forced oil-mist or circulating oil lubrication regimes. When lubricated with factory-filled synthetic high-speed grease, safe continuous velocity is maintained at approximately 75% to 85% of the maximum nominal limit, preventing thermal runaway.
To match diverse operational dynamics, CHG Bearing supplies 45*78.1-1 with multiple cage configurations: high-strength pressed steel ribbon cages for standard duty, solid machined brass cages (M/CA) for heavy vibration and shock loads, or lightweight glass-fiber reinforced polyamide cages (TN9/TVP) for high acceleration and ultra-low noise.
