Failures of Engineering Structures Caused by Weld Imperfections

摘要

The problematic of welding in terms of weld quality in dependence on service life of mechanical structures is discussed. Some examples of inadequate quality weld joints causing failure under load are described. Materials of the evaluated welds were following: S355 steel and Inconel 635 super alloy. Service conditions of homogeneous welds were different for both materials and weld quality was covered by Welding Procedure Specification. Using metallographic evaluation, the main problems were detected in a form of geometrical imperfections or insufficient penetration. These existing imperfections combined with static and dynamic load initiate the partial malfunction or failure of parts or constructions.