Hot take: you don't need to grind every weld flush on pressure vessels

I keep seeing guys spend an hour grinding down welds that are perfectly code-compliant. My old foreman at the Shell refinery in Houston showed me that ASME Section VIII only requires a smooth blend if it's over 1/16 inch. We did a leak test on a 300-psi vessel last month where we left the caps on and passed no problem. Saves a ton of disk wear and arm fatigue. Am I missing something or are we just chasing looks?

3 comments

3 Comments

jana50913h ago

Your mileage may vary but that ASME Section VIII thing about 1/16 inch is actually for the weld reinforcement limit not the blending requirement. You can leave the caps on but if you have a spot that's over that height you might need to blend it or risk the inspector flagging it on your next outage. We had a similar situation with a 400 psi tower where the CWI called us out on a cap that was close to 1/8 inch. Not saying you're wrong about the disk wear and arm fatigue though, that stuff adds up fast. Just worth double checking the specific paragraph in Section VIII before you tell the new guys to skip the grinder entirely.

sullivan.quinn11h agoRising Star

Bought a cheap set of micrometers and a weld gauge from Amazon years ago and started measuring every cap over 1/16 inch before the inspector even got near it. Saved us a lot of grinding time and arm fatigue because we only blended the spots that were actually out of spec. Made all the new guys measure twice and grind once until it became a habit. Never had an inspector flag us after that. Also kept a copy of the ASME paragraph printed and laminated in the weld shop so nobody could argue about it. Just made life easier all around.

ray6138h ago

Same deal with car detailing or even woodworking. People get so focused on making it look perfect that they forget the thing just has to work and pass inspection.