AWS d1.1 /RT acceptance criteria

[bhart192]

help: according to Fig 6.2 for a 1" weld the maximum indication can be just over 5/16" , however if there are two indications at 1/8" in size they can't be closer than slightly over 1" , doesn't seem to make sense , i can have a indication 5/16" in size but not two 1/8" indications closer than 1" am I reading the chart correct.

 

[JR97]

Bhart,

That is how I read it. AWS D1.1 is very strict on adjacent indications. The only wiggle room would be if the two 1/8" indications are separated by less than 1/16. Then you could call them a single indication < 5/16 in size.

JR97

 

[Duwe6]

Don't overthink it. These are empirically derived rules *that work*. There are many thousands of man-years of experience in using this Accept/Reject criteria, and it works.

But I agree, is seems counterintuitive. In a few years [decades?], somebody will apply Fracture Mechanics to the D1.1 and D1.5 criteria. Expect a LOT of changes then, generally towards accepting larger flaws. Mild steel is very 'forgiving'.