Flame Bending of Pipe for Alignment Control Panel SP-7 Project Report (The National Shipbuilding Program)

Abstract : The principles of flame straightening, long in use on plate structures in shipbuilding, have been applied to the problem of precision alignment of fluid system piping in shipbuiding and overhaul. Reduction of residual stresses by elimination of mechanically applied stresses to pipes for alignment prior to welding or bolting in place is a desirable objective. This project is a first effort to develop techniques of heat control and patterns of heating to achieve alignment without adverse effects to base metal. Extensive test in has been performed and results documented to provide aata base for refinement of procedures to be used in ship production and overhaul. It was not possible within available time and funding to reach definitive conclusions on CRES pipes, however for carbon steel and copper-nickel alloys, the report shows positive results. No significant detrimental effects of repeated controlled heating were found and sufficient bending is produced to warrant use of flame bending of carbon steel and copper-nickel pipe in shipbuilding.