Narrow Gap Gas Metal Arc ( GMA ) Welding Technologies †

Copyright © 2015 JFE Steel Corporation. All Rights Reserved. Abstract: This paper describes the latest implementation status of the narrow gap welding process by the high speed rotating arc method developed by JFE Engineering in 1980s. In case of the engine crankcases, adaptive control function of the welding speed corresponding to the variation of the groove width has been newly developed. Tandem welding system by one operator without watching the two equipment has been also employed, shortening the welding lead-time to less than half that of the conventional method. Furthermore, for innovation of the narrow gap welding, another oscillation pattern of the welding torch by the circular weaving has been added to the conventional equipment. In case of the turbine members, application range has been expanded to be able to apply to the inclined narrow gap joints, and it was confirmed that the groove width could be decreased from the conventional 13 mm to about 8 mm.