Meant to develop the most energy-efficient bearings, the project won the ELFORSK Award 2013.
Meant to develop the most energy-efficient bearings, the project’s results were so impressive that CeramicSpeed won the ELFORSK award 2013. CeramicSpeed has been working with a number of leading Danish industrial manufacturers and energy suppliers since 2009 to develop the most energy efficient bearings and to document their findings. The project has been partly financed by ELFORSK (the Danish Energy Association’s R&D department), and utilised both traditional steel bearings and CeramicSpeed LongLife insulated bearings.
Measurements taken on the large 6318 bearing show that the CeramicSpeed bearings with ceramic balls achieve a significantly lower operating temperature. This applies both with and without friction generating seals. CeramicSpeed bearings have a 20 – 45° lower operating temperature, both at high and low temperatures.
The run-down time was 2-4 times longer for CeramicSpeed bearings (158-424 seconds) than for standard bearings (69-134 seconds). This clearly demonstrates that CeramicSpeed bearings absorb less energy than equivalent bearings with steel bearings (see figure 1). Bearings with friction generating seals generally absorb more energy; however CeramicSpeed bearings still achieve a lower operating temperature and a longer run-down time and absorb less energy than standard bearings with steel balls. All in all the tests carried out document that the energy lost in a 6318 bearing is reduced by at least 50%.
Measurements on the smaller 6205 bearing also demonstrated that bearings with ceramic bearings have a lower energy loss than steel bearings. This applies both for standard bearings and energy-effective E2-bearings. The lower loss in CeramicSpeed was further demonstrated by measuring the run-down time on a Grundfos-Normmotor. All in all it can be concluded that energy loss in a bearing can be reduced by a minimum of 60-70% by using CeramicSpeed bearings instead of standard bearings.
Translated to energy conversion efficiency, this means that CeramicSpeed bearings increase the energy conversion efficiency by 0.7-1.3% on smaller motors, and 0.2-0.4% on motors of 90kW and above. A calculation of the payback time based purely on energy savings on a selection of motor sizes is shown in figure 2 below:
The ELFORSK project has generated essential documentation for the fact that (among others) the CeramicSpeed LongLife Insulate bearing, which is especially designed for use in electric motors, generates the energy saving which is advertised. The detailed information about other factors, such as the consequences of different operating temperatures, run-down times, RPM and ambient temperature, which has been generated throughout the study has also allowed CeramicSpeed to optimise their standard products.