T-bar rolling process with universal and edger mills

摘要

Use of T-bars in shipbuilding has increased recently. Although T-bars having a web height of at least twice the flange width are generally required for ships, the dimensions of existing hot-rolled T-bars are not suitable. As a result, T-bars for ships are typically fabricated by welding two plates. To solve this problem, a new rolling method for T-bars using a universal mill and edger mill was investigated. Finite element analyses of universal and edger rolling were executed to investigate the characteristics of side camber. Next, multi-pass rolling experiments simulating the rolling passes at a universal roughing mill and an edger mill were performed, and straight pure lead T-bars having satisfactory cross sections were obtained. However, the web heights at the top and tail ends were larger than those of the other part. Additional vertical rolls were applied to edger rolling to enable a slight reduction of the web height, and the web height deflection was eliminated by this new arrangement. The results of this research clearly demonstrated the potential of the new rolling process for producing T-bars of ships.