Ultrasound thickness gage 1

[Hercules28]

I want to measure thickness of Stainless steel tubes. (non destructively). I looked online and I found Ultrasonic thickness gages.

Does anyone here has any experience with these?
Any respected manufacturers of such equipment.?
I am interested in the best accuracy possible.
Within thousands of an inch if possible.

Thanks,

Herc

 

[JR97]

Hercules,

Ultrasonic Thickness gages are a good alternative if hard gaging is not possible. There are two phases to a measurement; calibration and measurement. During the calibration phase one or two (depends on the instrument you are using) hard gage thicknesses are determined, e.g. at the end of the tube. The instrument is adjusted to match the measured values. The ultrasonic thickness gage accurately measures the time it takes for the ultrasonic pulse to travel from the transducer, through the part, reflect off the opposite surface, and return to the transducer. When the adjustments are made you are actually telling the instrument the acoustic velocity of the material.

When you move to the measurement phase the instrument again accurately measures the time for the pulse to travel through the material. That time multiplied by the set material velocity will result in the distance or thickness of the part. The reason I went to that detail, is the accuracy of the measurement is primarily determined by how accurately the material velocity has been set. If the velocity of your material varies from where you calibrated to where you are measuring, you will get an inaccurate thickness reading. If the velocity is constant you can achieve accuracies of 1% thickness.

Another potential error source is part curvature. Be sure to calibrate on a similarly curved surface as the test part.

The two biggest players in the market in the States (at least in my opinion) are GE Inspection Technologies and Olympus NDT.

 

[blacksmith37]

I think another way to phrase it is that your calibration standards should be as similar as possible in dimension and material to the work piece.

 

[IRstuff]

And be similarly processed.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[Ron]

Krautkramer...good, reliable brand. Not cheap.

 

[dbooker630]

GE Inspection Technologies now owns the Krautkramer brand. I remember the old KBI 1102's.