Product Innovation from INA and FAG Kugelfischer

New Bearing Concept for Axle Drives Offers Considerable Customer Benefits 1)Lower Fuel Consumption 2)Reduced Running Noise Even After Long Service Life For the first time ever worldwide, double-row angular contact ball bearings ¨C so-called tandem ball bearings ¨C are now being incorporated in rear axle drives for passenger cars. Proven in extensive tests, this bearing concept not only increases the service life but also makes a significant contribution to lower fuel consumption. Another pleasant side effect for the car driver is that the problem of increasing running noise with higher mileage is considerably reduced. Up until now rear axle drives exclusively incorporated axially preloaded tapered roller bearings. However, these bearings require axial preload which leads to a high degree of sliding friction in the contact between rollers and inner ring lip due to their internal design. At high speeds or heavy loads, this can incur additional temperature increases with oil-sump lubricated axle drives, resulting in accelerated oil deterioration and loss of preload. Lost preload reduces the stiffness of the design. As a consequence, the gearing in the axle drive operates at a less favorable gear mesh, which leads to increased running noise ¨C adverse effects on the drive¡¯s service life cannot be ruled out. In order to improve the service life, the automotive experts from INA and FAG developed a worldwide unique double angular contact ball bearing for rear axle drives. Their solution: angular contact ball bearings, equipped with two rows of balls. Due to considerably reduced internal friction, these bearings require less lubricant and do not lose in stiffness as there is practically no wear. The absence of the unfavorable roller-lip contact means that the cause of the preload loss has been eliminated. Throughout the service life, the gear mesh position remains constant, resulting in improved acoustics and a positive effect on the comfort in the vehicle interior. Angular contact ball bearings of comparable size operate at approx. 50% reduced friction and thus ensure the high efficiency of the axle drive, which also becomes reflected in lower fuel consumption. Tests with individual bearings, complete shaft supports and axle drives have confirmed the advantages and functional capability of the new bearings for the application. Test rig measurements showed a fuel saving potential of some two percent. Manufactured at FAG, the new differential bearings are already proving their advantages in practical operation. Since the debut of the BMW 1, customers can convince themselves of INA¡¯s and FAG¡¯s expertise. And in just a few weeks the next testimonial will be rolling to the starting line ¨C the new BMW 3. Incidentally, it is equipped not only with tandem ball bearings from FAG but also with various other products from the Schaeffler Group. LuK supplies e.g. components for the active steering, INA delivers valve drive components for the BMW Valvetronic and FAG contributes the wheel bearings.