Hot Rolling of Large Gears

Abstract

Forming processes are generally characterized by a high degree of material utilization as well as short process times and, consequently, a decent economic efficiency. Furthermore, incremental forming enables the use of relatively low forming forces which results in a more compact design of the used machines. These conveniences are utilized in terms of roll forming with round tools to form gears and threads in a competitive way. Based on experiences gained over many years of researching rolling technologies, a cross-rolling process characterized by round tools with outer gearings was elaborated to realize a hot forming process of large gears at the Fraunhofer IWU. At actual project GEARFORM, a scaled sun gear demonstrator from wind gear application could be realized by hot rolling technology. An optimized rolling time was achieved by 32.5 seconds.