Tried a new weld procedure on a 3/4 inch boiler tube and got a surprise

We had a job in Toledo last month on an old coal plant boiler, and I decided to test a different root pass technique I saw online. Instead of my usual method, I ran a tighter arc with less filler on the first pass. The weld looked perfect on the surface, but the radiography came back showing incomplete fusion at the back. Had to cut it out and redo the whole section, which set us back a full day. Anyone else run into this with newer techniques on thick-wall tubing?

2 comments

2 Comments

patkelly25d ago

Did you check the heat input first?

milesrobinson24d ago

Oh sure, let me just check the heat input, why didn't I think of that. Probably because I was too busy staring at the smoke. Classic move, asking about the basics after the whole thing is already melted. Next time I'll bring my checklist to the fire.