Cross-brand designation analysis
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Same-model Comparison
Explore products that share a base designation across loaded brands, with dimensional agreement and data gaps shown clearly.
Automatic candidate selection
One base designation across loaded brands
Exact designations rank first. Dimensions, suffixes and other technical differences remain visible so the result is not mistaken for an interchangeability declaration.
Dimensions verified
“621” across 2 loaded brands
At least two brands share the same bore, outside diameter and width. Use Custom Compare when you want to choose exact suffix variants yourself.
Technical comparison
Choose exact variants instead →Brand differences at a glance
| 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 |
Automatic matching is a search aid, not an interchangeability declaration. Confirm the full suffix, tolerances, internal design and application limits before substitution.