Continuous four-roll plate bending: a production process for the manufacture of single seamed tubes of large and medium diameters

Continuous roller bending of plates is an effective process in the producti on of single seamed tubes of large and medium diameters. The process is cap able of a wide range of various tube diameters from the smallest of just la rger than the diameter of the top roller to the largest limited only by the handling capacity of the bender. It requires less investment in toolings c ompared to other bending processes. Relevant researches on roller-bending a re reviewed and referred to. Current roller-bending machines are discussed. In particular, the versatility of the four-roll bender and its ability to generate better circularity, thereby helping to reduce material wastage and amount of subsequent machining, are examined. This paper discusses not onl y the design considerations, but also the working principles and some relev ant bending mechanisms of the process. (C) 1999 Elsevier Science Ltd, All r ights reserved.