Estimation of weld size of partial penetration butt welds by ultrasonic testing

Partial penetration butt welds are widely used in order to reduce their weld metal for fabrication. it is important that the weld size is estimated accurately so that unpenetrated portion acts as a crack like flaw. The method to estimate the weld size and fatigue crack in weld was studied by ultrasonic testing (UT). UT was performed using angle probes, and pulse echo technique and pulse transmission technique were examined. Results show that the pulse echo decreased and the transmitted pulse increased as the weld size was increased. Furthermore, using the weld size estimated by UT and fracture mechanics, failure load was evaluated and compared with an actual failure load.