"Pipe welding Root pass"
Question:
"What effect will lack of penitration of the root pass have on a 14" sch40 pipe. Welder used 6011 rod for each pass (3 passes total). Root pass does have some penitration but does not meet ASME B31.9"
Answer:
The effects of lack of penetration (lop) at the root of a pipe butt weld may be (1) none, (2) localized corrosion, (3) lack of needed strength, or, (4) fatigue cracking, depending on the service.