General phase-difference model of round dies for inner and external helical profile rolling processes with radial-feed and through-feed

The motion characteristics between inner and external helical profile rolling processes and between radial-feed and through-feed rolling processes are widely different. To research and establish a phase-difference model of round rolling die (PDMRRD) ensuring the well connection of rolled helical profile by different dies is important to rapid assembly of geometric models in numerical analysis and to reduce the attempting rolling tests in industrial rolling process. The PDMRRD for inner helical profile rolling process with radial-feed was modeled, and the requirements of phase difference among rolling dies for inner and external helical profile rolling processed with through-feed were studied. Based on these, a general PDMRRD for inner and external helical profile rolling processes with radial-feed and through-feed was modeled, which is related to the number of starts of the workpiece, the number of starts of round rolling die (RRD), the number of RRD, and the consistency of the rotational direction for workpiece and RRD during the rolling process. The validity and availability of PDMRRD for inner helical profile rolling process with radial-feed and inner and external helical profile rolling processes with through-feed were verified by using the numerical and experimental methods.