Calculation of power losses and cooling of an industrial gear unit

In this Master’s Thesis, different methods for calculating thermal rating of industrial gear units are introduced. Thermal rating is calculated by estimating power losses and cooling power of the gearbox. Calculation methods for power losses introduced in this work are mostly standardized methods, which are based on work done by European researchers, universities and research centers. Background for calculation of cooling power is presented by using simplified equations for heat transfer. To find a suitable calculation method for power losses, cooling power and thermal rating of Santasalo Gear’s gear units, three different types of gears were calculated. Calculations were done with different methods and results were compared and discussed. It was shown that calculated values for power loss, cooling power and thermal rating vary significantly between different methods. Conclusion was, that calculation of thermal rating according to standard ISO/TR 14179-2 is suitable for Santasalo’s gear units, but the accuracy and reliability should be confirmed with test runs