Characterization of welded joints with Partial penetration on S355N structural steel

Abstract

Existing standards require welded joints with full penetration. It is considered that welded joints with complete penetration minimize the stress concentration in the root passage. However, there are numerous situations in the industry in which the load-bearing capacity of the welded joint with partial penetration is satisfactory. If the tests of partially penetrated welds show satisfactory load capacity, the benefits compared to fully penetrated welds are reflected in lower costs, i.e., less time is required to prepare the joint, and less additional material is needed, i.e., less time is required to make the welded joint. The paper presents the testing of butt-welded joints of structural steel S355N, with partial penetration, achieved by the MAG welding in the overhead position (PD) in the protection of the gas mixture. The samples were welded with different welding parameters and with different joint preparation, and the tests were performed by nondestructive methods (visual inspection, testing with penetrants and magnetic particles) and destructive methods (tension and bending tests, Vickers hardness testing).