A ship hull is largely made of curved plates, and some of them are doubly curved ones that are not developable. They are formed by the line heating method that has been used for a long time in ship construction. There have been a lot of efforts to automate the line heating process, and a practical algorithm for line heating information was developed. The algorithm, based on differential geometry and kinematics analysis of plates, was efficient in terms of computational time. Up to now, however, its applicability to the real shipyard process has not been evaluated. In this paper, we develop a software framework for heating line computation, test it with real ship hull pieces, and verify that the information from the algorithm matches worker's know-how in practice.