Design method of rolls for reshaping processes of pipes with pentagonal cross-sections

The manufacturing of the non-circular pipes made by reshaping process is becoming more and more important because of their utilizations as structural elements in almost all the industries. Despite of long history of the process, due to the complicated deformation behaviors of pipes during reshaping, the design procedures for rolls and pass-schedules mainly rely upon experience-based knowledge. In order to reduce labour and time for making new products, authors have developed a new roll design method. It bases upon the simulation technique by which analyses two-dimensional elasto-plastic deformations of the cross-sections of pipes. In this paper, the design method is used to determine all the intermediate cross-sectional profiles between the circular pipe and the pipe with the pentagonal cross-section. Through the study, useful knowledge and data concerning deformation of pipes for the design of rolls and processes are obtained. Furthermore, it is shown that there are good agreements between the results of the design method and the experimental results.