Computer aided design of rolls for reshaping processes from round pipes to “channel-type” pipes

The reshaping of round pipes into non-circular pipes is one of the most important processes in the tube/pipe industry. Due to recent industrial demands, the reshaped products have to satisfy a high level of specifications with accuracy in dimensions and variety of cross-sectional profiles. The design of rolls and pass-schedules, however, are still carried out relying on individual empirical knowledge and judgement, with the consumption of much time and labor. Under a situation like this, some kind of theory, numerical model and simulation method, which can provide reasonable knowledge and data concerning pipes’ deformations, are required for the design of rolls and processes. In this study, a two-dimensional elasto-plastic analysis method is extensively developed to investigate the deformation features of pipes’ cross-sections in reshaping processes from round pipes into non-circular pipes. It has become clear that through systematic numerical analyses of forward and backward deformation based on the developed method, roll-profiles that are suitable for making the required products, can be designed successfully. The developed method is usable to design rolls and pass-schedules for various types of reshaping.