Deformation Cracking of Single Fillet Weld and Selection of Welding Procedures for Avoiding its Cracking

Abstract

Heel cracking, a kind of cold cracking, is successfully reproduced by non-restraint T-type fillet weld cracking test. This crack is likely to be caused with decreasing vertical plate thickness and increasing heat input. This tendency can not be explained by the conventional concept of restraint cracking dealing with relatively thick plate in one dimensional field, but the generation of rotational deformation on the condition of vertical plate thickness smaller than critical thickness, h_cr. " These "results lead to the fact that this tvne of crack is characterized as deformation cracking in corimparison with restraint cracking.
The large sized fillet weld cracking tests are also conducted, and their preheat temperature for avoiding cracks is compared with that of non-restraint T-type cracking test. As the results, using the results of non-restraint T-type cracking test, the diagrams are established for avoiding single fillet weld cracking for given thickness, heat input and cracking index of chemical compositions of steel plate, P_N.