Rolling and plain bearings are extremely important for the function, cost-effectiveness and reliability of a wide range of industrial applications. Their continuous development offers considerable potential that can be used to support higher loads, increase operating life and improve performance. For more than 10 years, X-life has been the seal of quality for particularly high-performance products from the INA and FAG brands.
X-life products are characterized by significantly higher dynamic load ratings than previous standard products. The catalog range is continuously being expanded through the addition of new and performance-optimized X-life bearings that allow customers’ requirements to be fulfilled and the overall efficiency of machines and equipment to be increased. More and more catalog products are thus being replaced by their X-life versions.
Optimized design that improves overall cost-effectiveness
Under the same operating conditions, the operating life of X-life bearings is significantly longer or, alternatively, higher loads can be applied while maintaining the same rating life values. These state-of-the-art manufacturing technologies enable a better and more uniform surface over the whole contact zone between the rolling elements and raceway. The internal construction is designed for optimum functionality using state-of-the-art analysis and evaluation methods which ensures optimized contact surface geometry and more even internal load distribution inside the bearing. As a result, there is a reduction in the stress conditions present on the rolling elements and mating track under identical load. This produces a higher dynamic load rating, longer nominal rating life, less friction, lower bearing temperatures, as well as a reduction in the strain placed on the lubricant.
Tests have confirmed that optimizing bearing positions with X-life bearings allows the overall cost-effectiveness of the relevant application to be improved. The hydraulic systems used in wheel loader travel drives with a power transfer unit, hydraulic pumps, motors, and innumerable rolling and plain bearing positions are one example, as the overall efficiency of this application can be increased by up to two percent. For a wheel loader with 140 kW drive power, this means a total saving of around 9 kW. In an application with 1,000 wheel loaders operating for approximately eight hours a day, this gives an annual savings potential of approximately 26,000 MWh or a financial saving of around five million Euros and a CO2 saving of around 16,000 tons. In addition, optimization using X-life bearings ultimately means that the hydraulic pumps and motors can be made a size smaller.
Efficient gearbox bearing solutions for agricultural machinery: FAG tapered roller bearings in X-life quality
Thanks to their innovative internal design, FAG tapered roller bearings in X-life quality are an efficient bearing variant for pinion shaft bearing supports in tractor transmissions that is particularly suitable for the highest load requirements. Specially machined raceway, roller surfaces and optimized contact geometry between the rolling element end face and inner ring rib allows power loss to be reduced by up to 50 percent.
The improved surfaces allow an elastohydrodynamic lubricant film to be formed more quickly at low speeds during the start-up process and in field operation, which means that wear and friction – and thus the generation of high temperatures – can be reduced. Aforementioned design features not only save fuel, but also reduce the aging of the lubricant at the same time. The improved surfaces in the rolling contact and the use of higher-quality materials increase the dynamic load carrying capacity up to 20 percent, which in turn allows the operating life to be extended up to 70 percent.
The contact geometry between the rollers and the raceway (so-called profiling) has been revised and counteracts harmful edge pressure, plastification in the rolling contact in the event of shock loads and severe shaft tilting in the full load range (e.g. during field operation). This protects the bearings and thus the machine from premature failure. FAG tapered roller bearings in X-life quality increase the efficiency, durability and reliability of gearboxes in mobile driven machines and make a significant contribution towards reducing their lifecycle costs.
With FAG X-life tapered roller bearings, it is also possible to downsize tractor gearboxes while maintaining or even increasing their performance, thus achieving decisive advantages in terms of costs and competitiveness.
INA radial insert ball bearings and housing units in X-life quality: For a longer bearing life
Thanks to X-life quality, radial insert ball bearings and housing units for applications in agriculture, the food processing and packaging industry, and in textile machines also benefit from a 15 percent increase in bearing life, an expanded application temperature range of -40 °C to 180 °C and a high level of anti-corrosion protection through the use of Corrotect® N coating. An improved locking collar design also ensures higher clamping forces and secures seating on the shaft, due to optimized geometry and improved material properties. Reliable seals keep the high-quality bearing grease inside the bearing and prevent the ingress of contamination and moisture. This increases the durability of the bearing and extends the operating life of the machine.
FAG axial and radial spherical roller bearings in X-life quality
FAG axial and radial spherical roller bearings in X-life quality are characterized by increased robustness and load carrying capacity, lower friction levels and greater efficiency in addition to a longer rating and operating life. They are used where very high loads have to be supported and shaft deflections or bearing seat misalignments have to be compensated.
The design measures means that on average, FAG radial spherical roller bearings have a 50 percent higher limiting speed and allow the dynamic load rating to be increased by 15 percent and the nominal rating life by 60 percent due to the design of the rollers, which is characterized by an enlarged load-bearing contact surface. At the same time, the convex form of the roller end faces ensures a low-friction contact between the rollers and the rib.
Improved performance offered by FAG axial spherical roller bearings was made possible by changes to their geometry that increase the load rating, such as longer rollers and larger roller diameters. The rolling partners’ improved surfaces ensure that a lubricant film with an even higher load carrying capacity is formed, while improved osculation conditions and additional profiling optimize the rolling contact. This increases the dynamic load rating by 30 percent, reduces friction and, with an increase of 240 percent, more than doubles the rating life.
Bearings for screw drives – significantly higher performance thanks to X-life quality
In addition to reducing energy consumption, the technical optimization using X-life increases the dynamic load rating which, at approximately 10 percent, is significantly higher than the values achieved by previous bearing designs. This in turn increases the nominal operating life by up to 33 percent. As a result, the axial angular contact ball bearings have a longer operating life under the same operating conditions. Alternatively, the bearing support can be subjected to correspondingly higher loads while maintaining the same operating life. Design engineers thus have additional options for designing the bearing support.
In addition to the improvements made to the surfaces, the bearing ring material also undergoes a special heat treatment process. This makes the raceways of the inner and outer rings more resistant to solid particles and mixed friction. This in turn extends the operating life of the lubricating grease, as the strain placed on the lubricant is reduced. This heat treatment measure means that the operating life of bearings in X-life quality is significantly longer compared to that of standard bearings and competitors’ bearings. The significant improvement in the performance of the bearing support increases its overall cost-effectiveness, which means the customer benefits from a better price-performance ratio.
INA -D machined needle roller bearings: Efficiency with downsizing
INA’s -D needle roller bearings in X-life quality feature a newly developed, profiled steel cage produced by optimized forming methods that allows a significantly higher load carrying capacity to be achieved. The cage is designed in such a way that the number of needle rollers and the needle roller length can be increased while maintaining the same bearing dimensions. The larger number of rolling elements and the increase in their load-bearing length means that the load ratings of new -D needle roller bearings in X-life quality are up to 25 percent higher. This means that bearings installed in the same mounting space can be subjected to significantly higher loads. Viewed another way, the new -D needle roller bearings in X-life quality open up new design options for downsizing, i.e. a reduction in the size of machines and units while maintaining the same performance. For example: the X-life needle roller bearing NK20/16-D with a bore diameter of 20 mm and a width of 16 mm corresponds to the existing X-life needle roller bearing NK26/16 with a bore diameter of 26 mm in terms of load carry capacity. If the new bearing is used for downsizing, the section height of the bearing is reduced by 15 percent, the weight by 20 percent and the friction by 30 percent, while maintaining the same load carrying capacity.