The objective of this work was to evaluate a new chategory of weld support for the one-sided welding of carbon steel, using fiber glass and ceramic fiber tissues. This is a proposal of techonological innovation proposed, an evolution of the conventional ceramic support. The one-sided welding with this type of weld support was made in carbon steel with FCAW and GMAW. The efficiency of fiber glass and ceramic fiber was verified during the root weld bead. Several thicknesses and combinations of glass and ceramic fibers were tested. Working points were identified. The following variables were studied: root gap, welding current and travel speed. The results show that materials based on fiber glass are effective to support the liquid weld pool. The way the weld support was fixed in the welded joint also shown to be effective. It was possible to estimate a working range of the process, with root gap of 2,0 to 4,0 mm, heat input lower than 1,8 kJ/mm, pull welding technique with some oscilattion of the torch, thickness of the weld support higher than 1,6 mm. Macrographs of the welding joints show that there was penetration on the groove sides, adequate reinforcement in the root and no defects were observed.
One-sided welding; weld support; fiber glass; ceramic fiber
