TWI Industrial Member Report Summary 468/1993
By F J Blunt
Background
Single sided manual metal arc (MMA) welds in steel tend to have very poor root profiles. In particular the weld profile on the side to which access cannot be gained may be poor due to the weld metal failing to wet the sides of the preparation. While the welder has an important role to play in determining root profile other factors which are beyond his control. are also important. Previous work examined the role of flux composition in determining root soundness and profile. The present project explored the causes of poor wetting of the weld toes in the root of a single sided root run. Various methods were used to attempt to alter the behaviour of the solidifying metal in the root. These included surface coatings on the steel and powders introduced into the root gap.