UT 6dB Drop Defect Length Sizing

This video demonstrates measuring the length of a defect using ultrasonic angle beam 6dB drop method.
Equipment: Olympus EPOCH1000i UT tester, 70 degree, 4Mhz, 8x9mm transducer, carbon steel single V weld 0.625" thick base metal.
I work at Central Piedmont Community College in Charlotte, NC. Please visit our website to explore your NDE training needs.
Central Piedmont Community College NonDestructive Examination Technology Program
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[@Ace-is7ww]

you are truly an awesome Mentor
Thank you John!

[@nampoothiri1]

Awesome explanation! Really good for someone who is interested to learn UT. Thanks for the video

[@nishanttamrakar4700]

Nice explanation👍

[@umairsaeed8657]

Great explanation 👍🏼
Could you pls make a video on Beam Profile for ASNT or PCN exam ? That would be so nice of you
Thank you

[@salehinthedark7585]

thx its helpful

[@salehinthedark7585]

mr john can you do it in rounded pipe cause i face a problem when trying sizing defect in pipe not easy as the plate

[@gustavoporras5905]

Hi. How did you recognize the lack of fusion from the signal coming from the bottom of the weld? I suppose that is just happening just a bit before the end of the first leg...but I don´t know if there is other way to identify what is one or other. Thank you for your videos...I really appreciate your time and effort to explain these things.

[@johnnyb28227]

Good question Gustavo. The first thing that lets me know I am getting a signal at the root is the depth of my defect signal is at the base metal thickness. Using a 70 degree transducer I can detect this defect using the first leg, the fact that the signal is at the thickness of my base metal indicates the defect is open to the ID or root. This signal will plot just short of the weld center line and will have an identical signal from either side of the weld, this points to a lack of fusion at the root. Another thing that helps determine that the defect is a lack of fusion is slightly pivot your transducer and watch the signal, it will drop off very rapidly, this is because you are looking at a smooth machined surface, the weld prep.

[@mohamedattia633]

Nice explanation . I need full free course in ut , could you send me practical books useful in learning please ?

[@Taste_Budz]

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