Fatigue Life of Repaired Welded Tubular Joints

The subject of this study is to investigate the effect of repair on the fatigue life of tubular joints. six cracked specimens previously subjected to fatigue loading underwent weld repair. two of these specimens were shot peened before primary fatigue loading. it is shown that repair for the original specimens increases the fatigue life by roughly 150%. the increase of fatigue life for shot peened and repaired specimens is around 105%. the in-depth residual stresses are measured on the repaired joints before and after fatigue loading. it can be stated that repair made a remarkable improvement on the fatigue behavior of tubular joints examined in this investigation. however, where repair is not possible, shot peening can be a good alternative to improve the fatigue life of welded joints. if repair is planned to be carried out then shot peening may not be financially or technically justifiable.