Looking to the future: Calculating rolling bearings' remaining useful life

At the 2016 Hannover Messe, Schaeffler will be presenting a new digital service: The calculation of rolling bearings’ nominal remaining useful life during operation and thus on the basis of real load spectra. This service from Schaeffler is new on the market and offers machine operators a predictive maintenance solution that provides a far-reaching look into the future without the need for irregularities to occur and be detected on the drives first. Specialist visitors can learn about remaining useful life calculation through the “Drive Train 4.0” technology demonstration exhibit, a generic arrangement of motor, clutch, and gearbox that also shows further products and micro services from Schaeffler in the context of “Predictive Maintenance 4.0”. The core elements of the system for calculating rolling bearings’ remaining useful life on the Drive Train 4.0 are an innovative FAG Xeleris torque measurement module, data from the machine control system, and a model for calculating the local bearing loads in BEARINX, Schaeffler’s rolling bearing calculation and simulation program. The concurrent data recording by the FAG Xeleris is linked to the BEARINX software tool via the Schaeffler cloud, in which data are processed (i.e. classified) and the load spectra derived, in addition to the implementation of the actual rolling bearing calculation. The respective nominal remaining useful life for each bearing in the machine or system is calculated by subtracting the current runtime from the nominal rating life, which is continuously re-calculated at time intervals that can be freely defined. The customer can view the resulting remaining useful life data for every bearing in the machine on his or her internet-capable end device. An alarm signal is given by e-mail once the calculated load spectrum indicates that a bearing position is within “x” operating hours or calendar weeks of reaching the end of its nominal bearing rating life. The comparison of the remaining operating life of the rolling bearings in a production facility with the next planned maintenance work allows the operator to control the load conditions in his or her production processes in such a way that the bearings will not fail before the planned maintenance interval is reached. If no bearing replacement is carried out after the calculated remaining operating life has expired, it must be expected that a bearing failure will soon occur. Combining this solution with the FAG SmartCheck condition monitoring system makes it possible to sound the alarm earlier in the event of irregularities by lowering the SmartCheck system’s alarm thresholds once the remaining useful life has expired. This gives operators and maintenance technicians a longer response time in which to implement maintenance measures. The ongoing calculation of the remaining useful life of rolling bearings and guidance systems – which frequently has the same significance as the remaining useful life of entire drives – allows maintenance work and replacement part orders to be planned early, maintenance intervals to be extended through adjustment of the machine capacity utilization, and the capacity utilization of individual axes or even entire machines to be increased until the next maintenance interval.