Lubricant is a vital component for the optimal bearings performance keeping under control running speed and temperature, torque and noise level and bearing life.
ISB bearings are lubricated with grease, except when specific fluid lubricants are used to further reduce friction.
Full Ceramic bearings are also lubricated with oil instead of grease.
Hybrid bearings require only a marginal lubrication compared to Steel bearings due to the lower friction coefficient and lightness of the balls.
However, as hybrid bearings are often selected for higher speed applications than full ceramics, suitable lubrication is advised.
SEALING AND PROTECTION SYSTEMS
Mostly, ISB bearings are sealed on both sides, in order to prevent contaminating particles inside the bearing. These seals can be made of metal or nitrilic rubber.
RS Type Seal
NBR seal in contact with the external surface of the inner ring, to provide optimal protection for the bearing, but limiting the potential rolling speed because of friction.
RZ Type Seal
Low friction NBR seal that guarantees optimal bearing protection even at high rolling speed without creating friction.
Z Type Shield
Metal shield that provides basic bearing protection without creating friction or limiting rolling speed.
ISB bearings are also sealed on both sides:
• 2RS: one RS type NBR seal on both sides.
• RS/RZ: high precision sealing with a NBR seal type RS on the application side and a NBR seal type RZ on the opposite one.
• ZZ: one metal shield on both sides.
Steel is by far the most common material used to manufacture bearings.
Steel bearings are really very effective, and significantly decrease friction when rolling, compared to other systems such as bushings.
ISB Steel bearings tests show that the use of superior quality materials makes their average life (in the same load conditions and speed than standard) up to 1.5 times longer than standard.
Depending on the different alloys and heat treatments, two main product families can be identified:
ISB Chrome Steel bearings
These are the most used in sports applications and are consequently available in all the most common dimensions, representing the baseline of the portfolio.
• High hardness for long life cycle
• Stable up to 120°C
ISB INOX bearings
When corrosion represents a risk, the ISB Stainless Steel bearings are the solution to give resistance to oxidation from exposure to moisture.
• Good corrosion resistance to water and many weak chemicals
• Stable in a wider temperature range compared to 100Cr6 Chrome Steel
• Hardened by heat treatment but softer than Chrome Steel (80% load capacity of 100Cr6)
Ceramic materials feature chemical and mechanical properties that make them the ideal choice for the most demanding environments and working conditions. ISB has selected two types of ceramic materials to streamline the dedicated product offering: ZrO2 (Zirconium dioxide) and Si3N4 (Silicon Nitride).
The main technical advantage of ceramics compared to steel is the coefficient of friction: being up to 10 times lower, it is able to provide an extremely smooth operation, to generate less heating, less wear and therefore to prolonge durability.
ZrO2 is the preferable choice for full Ceramic bearings due to its noteworthy mechanical properties when compared to the weight unit.
• 75% of the density of steel
• High corrosion resistance
• Wide temperature range without cage
• Higher flexural strength and lower elastic modulus than other ceramics
Silicon nitride is the most popular material for the balls in hybrid bearings because of its high wear and abrasion resistance.
• 40% of the density of steel
• Low coefficient of thermal expansion (25% compared with the one of a steel)
• Superior corrosion resistance to water, salt water, acids and alkalis
• Very wide temperature range
Properties of ceramics and steels can be smartly combined to get the maximum out of their potential.
• Hybrid series: Chrome Steel bearings and silicon nitride balls
• Hybrid Inox series: Stainless Steel bearings and silicon nitride balls
• Ceramic series: ZrO2 full Ceramic bearings
The attention to detail to get more and more stunning results has always characterized the world of racing, where every single saved watt is decisive to stand out. To meet its demanding needs, ISB Sport engineers have developed coatings with the main objective of maximizing the smoothness of bearings, thus pushing the level of performance beyond the limits set by conventionally used products.
The choice of superior quality materials, the refinement of production techniques and the application of surface coatings on a nanometric scale, have allowed to obtain a drastic reduction in the energy dissipated by friction: the net result is a saving in terms of power available to the runner or pilot.
Coated bearings have been so far extensively tested by professionals, enabling ISB Sport engineers to measure:
. 88% – 90% reduction in friction
. Power savings of 7.15 to 9.45 watts
. Corrosion resistance up to 1500 hours
These coated bearings best express their potential in the extreme racing conditions that are found in motorsport, cycling and roller competitions, where ISB Sport has always been present to collect the feedback of professional pilots and athletes.