Extended Evaluation of Pitting Degradation Tests to Increase the Remaining Useful Life of Gear Wheels

Abstract

Within this work, the potential of an operating strategy is analysed based on test runs in laboratory environment, field tests as well as simulations. The operating strategy is used to increase the remaining useful life of gear wheel pitting by reducing the local stress at the weakened tooth. The local stress reduction is achieved by applying an adapted periodic input torque to the transmission and shift the minimum in the area of the weakened tooth. All the other teeth undergo a higher stress and therefore compensate the reduction. To analyse the potential of this strategy, the evaluation of pitting degradation tests has to be extended to all teeth using data from test runs as well as field tests. Both analyses show great potential as many teeth are totally intact. Finally, a simulative approach was carried out to quantify the potential and to show a reference value for the accuracy of the measuring system. As a result, for an increase in lifetime of 10 %, the measurement system has to locate pittings with a size smaller than 1 % based on the total tooth flank. If the pitting is located even earlier, a maximum of 38 % increase in lifetime is possible.