Operating behavior and performance of oil-lubricated plastic gears

Plastic gears and their numerous applications have become an integral part of industrial practice. In particular, the ability to produce large numbers of gears cost-effectively using injection molding techniques is making a significant contribution to growing market shares. Compared to conventional steel materials, however, the material properties of thermoplastics differ fundamentally. In particular, the high temperature dependence of the material properties and the lower strength pose challenges for designers. Against this background, theoretical and experimental studies on the operating and service life behavior of different thermoplastic materials have been conducted and evaluated. In addition to theoretical investigations on the tooth flank load carrying capacity, comprehensive measurements on temperature behavior were carried out and compared to common methods of temperature calculation for plastic gears. Experimental investigations on the tooth flank load capacity by means of back-to-back tests of different materials and their evaluation show the potential of thermoplastic materials for the application in power transmitting drivetrains. This contribution will give an overview of the performed research work and summarizes main results of these studies.