66FC46340 bearings ( 330 mm x 460 mm x 340 mm) have the advantages of Extremely high radial load capacity, high rigidity, separable design, and are therefore widely used in the metallurgical rolling mills, large gearboxes, and heavy-duty extrusion presses.

| Part Number | 66FC46340 |
| Interchangeable | KOYO 66FC46340 |
| Desgin Figure | 1-2 |
| Cage | Machined brass cage |
| Radial internal clearance | C3 |
| Seal | Open |
| Bearing Type | Four-row cylindrical roller bearing for cold rolling mill, hot rolling mill, billet mill |
| Design type | Outer ring with rib, One inner ring |
| Bearing Weight [lb] | 379.191 |
| d φ Inside [inch] | 12.992 |
| D Φ Outside [inch] | 18.110 |
| B Width [inch] | 13.386 |
| Fw Raceway diameter inner ring [inch] | 14.331 |
| C [inch] | 13.386 |
| r min Chamfer outer ring | 2.1 mm |
| r1 min Chamfer inner ring | 2.1 mm |
| Cr Radial Dynamic [lbf] | 867728 |
| C0r Radial Static [lbf] | 2056920 |
| Mounting dimensions | |
| da min shaft [inch] | 13.465 |
| Da max housing [inch] | 17.638 |
| Da min housing [inch] | 16.850 |
| ra max Fillet radius [inch] | 0.079 |
| rb max Fillet radius [inch] | 0.079 |
The 66FC46340 Four-row cylindrical roller bearings mainly consist of an inner ring, an outer ring, four rows of cylindrical rollers, a cage, and a spacer. Common structures use a configuration of double outer rings (each with double raceways) and a single inner ring (with four raceways), or an interchangeable combination of inner and outer rings. Axial positioning and load distribution are achieved through the spacer.
The advantages of four-row cylindrical roller bearings are their extremely high radial load capacity, high rigidity, and the line contact between the rollers and raceways, resulting in a low coefficient of friction and allowing for high-speed operation under heavy loads. They can also be used as floating end bearings, capable of withstanding axial displacement caused by thermal expansion, and are easy to install and maintain.















