Influence of lack-of-fusion defects on load capacity of MAG welded joints
Pressure vessels operating at elevated temperatures and pressures are made of creep resisting plate and welded from individual components using the MAG welding process. The paper proposed focuses on the occurrence of lack-of-fusion defects in MAG welded plate components of pressure vessels. Lack of fusion, which is a planar defect and is, therefore, difficult to detect by common NDT methods, can result in catastrophic consequences since the latter do not only damage a pressure vessel but also jeopardize the environment and workers health. The present paper deals with a research on the influence of a welding speed in welding of plate components made of S235JR steel of 8 mm in thickness, special care being taken to deliberately produce lack-of-fusion defects and possibly other weld defects. Test pieces prepared so as to contain various lack-of-fusion defects were subjected to destructive tensile testing. The force required for a weld failure was compared to actual weld defects. In the test pieces produced with lower welding speeds, a failure occurred in the welded joint and along a lack-of-fusion defect. In the test pieces produced with higher welding speeds, however, a fracture occurred outside a weld, although lack of fusion was present in the weld. Parallel to the tensile tests, radiographic examinations of lack-of-fusion defects were conducted and relevant micro sections were analysed. The aim of the study conducted was to elaborate a guideline for quality welding of plate components of pressure vessels.
MAG welding speed lack of fusion defects tensile test radiographicexamination.
Milo(s) JOVANOVIC Janez GRUM Miro URAN
Welding Institute, Ptujska 19, 1000 Ljubljana, Slovenia.2 Faculty of Mechanical Engineering, Univers Faculty of Mechanical Engineering, University of Ljubljana, Askerceva 6, 1000 Ljubljana, Slovenia
国际会议
第十七届世界无损检测会议(17th World Conference on Nondestructive Testing)
上海
英文
379-386
2008-10-25（万方平台首次上网日期，不代表论文的发表时间）