I've been confusing about expression "Instrument with attenuation : b-a-c" in AWS D1.1 2006 Sect.220.127.116.11.Could you please explain me about it, And when we have to use the formula(b-a-c) instead of the a-b-c? As my knowledge that most UT Technicians only use the a-b-c when they evaluate every defect found.Thanks in advance for further kind explaination.
Re: Instrument with attenuation : b-a-cIn Reply to zaidi at 05:18 Jun-16-2009 (Opening).
Some of the UT instruments "in the old days" had atenuation controls rathe rthan gain controls. It would reduce gain as you turned it up rather than increase gain. I am not even aware of any modern day instrumentsthat have it.
It's just the opposite so AWS used "b-a-c=d" instead of "a-b-c=d".