Atlantic Marine and Edison Welding Institute (EWI) have completed the NSRP sponsored Line Heatingproject. Based on the success of this effort, the U.S. Navy is now funding the project team for follow-on work. The NSRP project developed and demonstrated a semiautomatic method to form plates using theapplication of heat from an oxy-fuel torch. The project included a device to hold the torch, predictive software, and recommendations on heat line patterns required to produce several shapes of interest.
The current industry practice relies on manual trial-and-error work by experienced craftsmen. Widespreadinterest in the ability to accurately predict and induce curvature in plate is evidenced by the large volume of research that has been dedicated to this area and ongoing attempts both in Europe and Asia to develop and implement this technology. The streamlined finite element modeling technique developed as a part of this effort vastly improved the speed of the computation; however, the time needed to predict the desired curvature limits the process. Through the use of a line heating device, what once was a manual process taking multiple days to complete based on trial and error is now a semi-automated process that takes approximately four hours, a dramatic improvement but still short of the four hour goal of the project. This aspect of the project is being pursued in a follow-on project, CNC Thermal Plate Forming, funded by the Office of Naval Research through the MANTECH Centers of Excellence.
An additional technique used in manual line heating, which is being addressed in the follow-on project, isthe need for a torch holding device to scribe a triangular heat pattern, typically used during the manual line heating process.