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CUSTOM / 08 MAX
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| Parameter | TIMKEN621 / 61253.975 × 120.65 × 41.275 mm | KOYO621/61253.975 × 120.65 × 41.275 mm |
|---|---|---|
| Comparable specifications | ||
| Brand | TIMKEN | KOYO |
| Designation | 621 / 612 | 621/612 |
| Product family | TS - Tapered Single | Single-row / Inch series |
| Detailed type | Tapered roller bearings | Tapered roller bearings |
| Series | 615 | — |
| Bore diameterd | 53.975 mm | 53.975 mm |
| Outside diameterD | 120.65 mm | 120.65 mm |
| WidthB | 41.275 mm | 41.275 mm |
| Basic dynamic load ratingC | 207 kN | 218 kN |
| Basic static load ratingC0 | 244 kN | 217 kN |
| Fatigue load limitPu | — | 34 kN |
| Limiting speednG | — | 3500 r/min |
| Mass≈m | 2.18 kg | 2.213 kg |
| Precision class | ABMA Class 2 | — |
| Sealing | Open | — |
| Cage | Steel cage | — |
| Calculation Factors | ||
| K Factor | 1.86 | — |
| Y1 Factor | 1.91 | — |
| Y2 Factor | 0.00 | — |
| Y0 Factor | 1.05 | — |
| E Factor | 0.31 | — |
| Cg Factor | 0.0694 | — |
| Classification | ||
| Official Category Path | — | Tapered roller bearings - Single-row - Inch series |
| Official Classification 1 | — | Tapered roller bearings / Single-row / Inch series |
| Manufacturer Identity | ||
| Material Number | 000000000100031247 | — |
| Official Class Key | — | 050-010-020 |
| World Assembly Part Number | 621_612 | — |
| Inner Ring Part Number | 621 | — |
| Outer Ring Part Number | 612 | — |
| Drawing Number | A-3310 | — |
| Upc | 0013992331113 | — |
| Official Source System | CORE BP - DS DF | — |
| Official Last Run | 2026-08-23T20:02:47.153 | — |
| Product Identity | ||
| Type Description | TS - Tapered Single | — |
| Construction | Single Row Tapered Roller Bearing Assembly | Imperial Series | 2.1250 in Bore | 4.7500 in OD | 1.6250 in Width | Open | Cylindrical Bore | Steel Cage | Precision ABMA Class 2 | — |
| Number Of Rows | 1 | — |
| Tapered Bore | N | — |
| Technical Data | ||
| d | — | 120.650 mm |
| T | — | 41.275 mm |
| B | — | 41.275 mm |
| C | — | 31.750 mm |
| Overall Width | 47.375 mm | — |
| R(Min.) | — | 3.6 mm |
| Radial Rating | 53,800 N | — |
| R1(Min.) | — | 3.2 mm |
| Axial Rating | 28,900 N | — |
| Basic Load Ratings : Cr | — | 218 kN |
| Dynamic Rating C1 | 207,000 N | — |
| Basic Load Ratings : C0R | — | 217 kN |
| Dynamic Rating C90 | 53,800 N | — |
| Fatigue Load Limit : Cu | — | 34.0 kN |
| Dynamic Axial Rating Ca90 | 28,900 N | — |
| Limiting Speeds(Grease Lub.) | — | 3500 min-1 |
| Dynamic Axial Rating Ca1 | 112,000 N | — |
| Limiting Speeds(Oil Lub.) | — | 4600 min-1 |
| Static Radial Rating C0 | 244,000 N | — |
| Load Center Spread : A | — | 27.3 mm |
| Extended Dynamic Rating Ce | 0 N | — |
| Constant :E | — | 0.31 |
| Static Axial Rating C0A | 223,000 N | — |
| Axial Load Factors : Y1 | — | 1.91 |
| Axial Load Factors : Y0 | — | 1.05 |
| Da | — | 105.0 mm |
| Db | — | 110.0 mm |
| Ra(Max.) | — | 3.6 mm |
| Rb(Max.) | — | 3.2 mm |
| Mass(Refer.) | — | 2.213 kg |
Independent reference comparison based on the manufacturer data currently loaded. Always verify current limits, tolerances and suffix definitions with the official source before engineering selection.