Why choose hybrid ceramic bearings to take place of steel bearings?
(1) High temperature resistance, small coefficient of thermal expansion of ceramic ball, in high temperature environment will not cause expansion of bearing ball due to temperature, which greatly improves the service temperature of the whole bearing. The temperature of common bearing is about 160 degrees, and ceramic ball can reach above 220 degrees.
(2) High speed, oil-free self-lubrication of ceramic ball and small coefficient of friction of ceramic ball result in high speed of ceramic ball bearing. The bearing with ceramic ball is more than 1.5 times the speed of general bearing.
(3). Long service life, no grease can be added to the ceramic ball, which means that even if the grease dries out, the bearing can still operate, thus avoiding premature bearing damage caused by grease loss in common bearings. According to our tests and feedback from some customers, the service life of bearings with ceramic balls is 2-3 times longer than that of ordinary bearings.
(4) Last but not least, insulation. The bearing with ceramic ball can insulate the inner and outer rings of the bearing, because the ceramic ball is an insulator. The insulation effect can be achieved by using ceramic ball between the inner and outer rings of the bearing. This allows the bearing to be used in an electrically conductive environment.
Full ceramic or hybrid ceramic?
When most people think of ceramic bearings, they are usually referring to hybrid versions. Hybrid bearings sit in the middle of ceramic and steel, typically including stainless steel races or rings and ceramic balls.
The steel inner and outer rings of a hybrid bearing can be machined to very close tolerances, meaning that they are best suited for applications such as electric motors, laboratory equipment and machine tooling.
On a grinder machine for example, 25% higher revolutions per minute (RPM) can be achieved by adding in ceramic hybrid bearings and synthetic grease lubricant owing to the reduced friction. Grinding spindles with hybrid ceramics may run 4000 hours without problems, compared with 3000 hours with steel bearings.
Hybrid bearings can also lower temperatures by nearly 50%. In a horizontal machining centre, switching from traditional bearings to the hybrid alternative has been shown to drop bearing temperature from 60 °C to 36 °C at 12,000 RPM.
Using a hybrid bearing combination allows for higher speeds than full ceramic options, as the less brittle metal rings are not as prone to sudden catastrophic failure under high speed or load. That said, a hybrid bearing’s corrosion resistance pales in comparison to a full ceramic equivalent.
Specifying the right bearings for extreme environments has always been a complex issue. But just as Zirconia clarified the origin of life, asking these three questions will help with the decision making process.