In the plate bending process by line-heating, the decisions on which part of the plate should be heated and in which direction are usually made by skillful workers. However, the number of skilled worker is reducing rapidly and this becomes a serious problem in shipyard today. To solve this, the authors proposed a method to make these decisions based on theoretical analyses focussed on inherent strain in the previous report. The potential usefulness of the method was demonstrated through example problems dealing with mathematical ideal geometry. In this report, comparison between the theoretical prediction and the real practice in the shipyard to form curved members of ship hull are made and it is attempted to visualize the knowledge of skilled workers, which was unvisible, using computer graphic images showing inherent strain. Further, it is demonstrated that the same idea can be applied not only to make decisions on line-heating process but also to design the total plate bending process including those using the bending roller and the press machine.