SKF in Sweden has developed a new family of bearings that reportedly reduces friction and energy consumption by at least 30%, compared to standard ISO products.
SKF President and CEO Tom Johnstone calls the new bearings an innovation that besides saving energy, matches the service life and load-carrying capacity of standard ISO bearings.
SKF researchers used sophisticated computer-modeling tools and proprietary software to attack virtually every source of bearing friction. With roller bearings, for instance, improvements resulted from tighter bearing specifications, refined internal geometry, and high-precision manufacturing. Specifically, design modifications affected the polymer cage, roller topography, raceway and guiding-flange topography, and raceway geometry.
The company also optimized the number of rollers and modified the raceway to reduce the weight of rotating parts by about 10% — without degrading performance. Lighter bearings are more efficient because it takes less power to move the rolling elements. The moving parts also have lower inertia, thus reducing the chance of skidding and smearing which affect performance and service life. In addition to lower energy consumption, the bearings generate less heat and run cooler, extending lubricant life.
One example of the bearing's potential: If every wind-turbine gearbox bearing worldwide was replaced with Energy Efficient tapered roller bearings, the turbines would generate an estimated extra 770 million kW-hr per year. That equals the monthly energy consumption of 1 million Swedish households.
SKF's Energy Efficient tapered roller bearings will initially target industrial segments where power consumption exceeds 1 MW. Such applications include wind-energy turbines, ship and train transmissions, large conveyors and extruders, and other heavy industrial applications. Initial size range will be 200 to 600-mm OD.
New deep-groove ball bearings are also said to reduce friction by at least 30% in most applications. Production will initially cover smaller-diameter sizes for light to medium-duty machinery. In particular, target applications include industrial electric motors driving pumps, compressors, fans, and conveyors.
Energy Efficient bearings meet ISO standard dimensions and can replace other bearings in most applications. The product family currently includes the two most-commonly used types: deep-groove ball bearings and tapered roller bearings. SKF may extend the technology to other designs, including spherical, toroidal, and cylindrical roller bearings and angular-contact ball bearings. Manufacturing will begin in the second half of this year.