April 5, 2006

NTN Develops
"High-Load Capacity Tapered Roller Hub Bearings for SUVs"

[Maximizing the number of rollers to attain long service life and high stiffness!]

The NTN Corporation has developed "high-load capacity tapered roller hub bearings" that provide longer service life and higher stiffness for pickup trucks and SUVs, where conditions are severe.

Hub bearings with steel balls are used in passenger cars, but in pickup trucks and SUVs, hub bearings with tapered rollers are used to attain higher load capacity and higher stiffness. Compared to hub bearings for passenger cars, tapered roller hub bearings for pickup trucks and SUVs are often used under heavy loads and with vehicles becoming maintenance-free, longer service lives are required. These demands are severe enough that it has become difficult to meet them by just improving previous materials, heat treatment procudures, etc.

At NTN, the internal design specifications were drastically reviewed. Bringing the cage closer to the outer ring while keeping the same outer diameter dimension made it possible to increase the number of rollers to the ultimate limit. The gap between rolling elements is minimized without reducing the cage strength. These new design specifications attain 20% longer service life and 7% higher stiffness without changing the bearing size.

These newly developed items will be widely deployed in the market as products that can contribute to improved automobile reliability and higher functionality.