Review of the Definition of Weld Penetration, Depth of Fusion and Throat Thickness on Fillet Welds

Abstract

In this study, definitions of Weld Penetration (WP), Depth of Fusion (DOF) and Throat Thickness (TT) in fillet welds according to related standards are evaluated. Each standard makes its own definition related to WP, DOF and TT. Moreover, when looking at these standards, it is seen that definitions are always made in terms of unit of length. In many studies, assessment of fusion or penetration (FOP) rate on fillet welds is performed as the ratio of the maximum FOP depth to the material thickness. Depth assessment taking into consideration unit of length is not ideal for accurate evaluation of FOP rates especially on fillet welds. In the evaluation made in terms of unit of length, FOP rate can be approximately 50 percent more than the evaluation made in terms of unit of area. Method taking into consideration unit of area will be more suitable as it allows accurate assessment of FOP rates in welded joints. In this review, in addition to evaluation of the definitions of standards, it is also suggested that the evaluation of FOP rate on fillet welds should be determined in terms of unit of area rather than length.