Small OD Tube External UT Device 1

[TiffyEng]

Can anybody suggest some good UT devices / methods for measuring wall thickness of tube externally in the range 1/4" OD to 1" OD?

Thanks

 

[EdStainless]

My favorite is made by Dakota Ultrasonics. They are not cheep ($2k), but they run in echo-echo mode for better accuracy.
We had a small diameter med freq sensor and a med size lower freq one for doing tube from 3/16"x0.012" thru 4"x0.225".
Up to about 0.050" wall we trusted it to 0.0001".

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P.E. Metallurgy, consulting work welcomed

 

[TiffyEng]

Hi thanks for the reply. Is there anything special about the transducer for this kind of application or are they just a smaller diameter?

 

[EdStainless]

The freq that you pick is related to the material (modulus) and thickness.
If you go to them with that info they will recommend probes.
We used official couplant goo, other things work (like KY) but you would be surprised to know how much chloride is in a lot of products.
But some spare tips (delays) for your probes, as they get worn or damaged it be harder to get good readings.
Have a couple of ref pieces, ours were about 2" long and hung from the device on a cord. It lets operators know that everything is working fine.

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P.E. Metallurgy, consulting work welcomed

 

[TiffyEng]

Thanks a lot for the advice.