I recently had a friends weld get rejected by xray for a concave bead. Repaired it, reshot it, and it came back rejected for IP. Two times in this last year I've heard this. Both times, same example. Is it just a bad xray tech or is it a change in the rules today?
Paul W Cameron - CWI
A friend eh?
Let me preface this by saying, "I'm no RT Guy." but, a concave bead in a radiograph could easily mask Incomplete Joint Penetration (IP).
A concave bead will appear darker (because it's thinner) than the base material around it when viewed in a radiograph. Once that concave bead is repaired (adding more weld [making it thicker then base material]) the area that was once dark is now light and any IP would be clearly visible.