Robustness tells you more about:
Shock resistance
Load carrying capacity
Mounting and dismounting facility
this is the basis for an appropriate bearing!

Robustness mainly depends on:
Bearing material and quality of heat treatment Robustness is the basic feature for SKF Inline bearings.Manufactured from steel of SKF own plants, the worlds purest bearing steel, leads to improved heat treatment quality and so to adequate hardness and wear resistance.

Shape of raceways and balls
Thanks to top class design and manufacturing process, SKF ball bearings have an optimal geometry leading to very high wear-resistant raceways. SKF also uses the hardest steel balls so that one can ensure SKF bearings are the world most popular Of course SKF bearings with ceramic balls are even more robust because of the increased hardness of the ceramic balls!

Lubricant quality
It does not sound logical that an appropriate lubricant helps a bearing being to be more robust. Nevertheless, the use of a grease with extreme pressure additives is beneficial for bearings working under heavy loads and shock loads.

Cage stress-resistance
The role of the cage is to separate balls to prevent direct contact and lubrication problems. When the bearing is submitted to high shocks or high loads the balls are intended to escape from the load zone and the cage has to support part of the load to retain the ball in position. Also, when braking axial loads can generate torsion in the cage.Therefore, for aggressive purpose SKF recommends to use fibreglass reinforced cages.