3R8-79N9 bearings ( 1762.0488 mm x 2169.922 mm x 147.066 mm) have the advantages of The strongest load-bearing capacity, independently bears the load, and has a robust and reliable structure, and are therefore widely used in the Heavy tower cranes, truck cranes, large excavators, wind turbines and tunnel boring equipment.

| Part Number | 3R8-79N9 |
| Bearing Type | Heavy Duty Three Row Roller Slewing Rings With Internal Gears |
| Gears type | Internal Gear |
| Units | inch |
| Seal | Seal on one side only |
| Seal Material | NBR (Nitrile Butadiene Rubber) |
| Rows NO. | Three |
| Outside - OD Φ [inch] | 85.43 |
| Inside - ID φ [inch] | 69.372 |
| IO [inch] | 77.72 |
| OI [inch] | 77.44 |
| Overall Hight - HT [inch] | 5.79 |
| OH [inch] | 5.43 |
| IH [inch] | 4.49 |
| K [inch] | 1.30 |
| Mounting Holes - OBC [inch] | 83.268 |
| OU [inch] | 1.30 |
| No. Holes - OBC | 48 |
| Mounting Holes - IBC [inch] | 73.819 |
| IU [inch] | 1.30 |
| No. Holes - IBC | 44 |
| PD [inch] | 70.286 |
| DP [inch] | 1.75 |
| No. Of Teeth | 123 |
| F [inch] | 4.13 |
| Tooth Form 20˚ | STUB |
| Gear hardness (BHN) | 250-300 |
| Max. Tangential Tooth Load [lbs] | 47940 |
| Nominal Capacity Compressive Thrust [lbs] | 2779000 |
| Nominal Capacity Moment [ft-lbs] | 3997000 |
| Nominal Capacity Curve No. | 8-79 |
| Nominal Capacity Radial [lbs] | 396000 |
| Weight [lbs] | 2293 |
The 3R8-79N9 Three-row roller slewing bearings mainly consist of an upper ring, a lower ring, a middle ring, three rows of independent rollers (two rows of axial rollers at the top and bottom, and one row of radial rollers in the middle), spacers, and a sealing device. The three rows of raceways are separate and do not interfere with each other, resulting in a clear structural layout.
Three-row roller slewing bearings have the strongest load-bearing capacity. The three rows of rollers respectively bear axial force, radial force, and overturning moment, resulting in a reasonable load distribution. They exhibit excellent rigidity and impact resistance, have a long service life, and are suitable for heavy-duty rotation under extremely heavy loads and harsh working conditions.















