NDT in yacht surveying - techniques, effectiveness, availability?

Alan ashore

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While this is an area I've wondered about for some time, the thread is of course prompted by the recent CR MAIB report.

Obviously a broad subject, but the focus I have in mind is on the use of relatively sophisticated techniques to verify a yacht's structural integrity. I can see that there are specialist companies offering services including thermal imaging, ultrasound and x-ray, but my impression is that apart from x-raying keel bolts, little application of such techniques is being made by, or on the recommendation of, the average local surveyor doing a pre-purchase survey on an AWB or MAB. He or she as I understand it will rely principally on eyes and ears - especially the latter in conjunction with a hammer, to find evidence of potential structural issues.

I imagine that, in the normal course of progress, there will be an increasing take up of more sophisticated methods - but to what extent is this already happening? Should the industry be seeking to accelerate that? What are the barriers? etc.

In any case I would love to hear views and experiences from owners, surveyors, specialists, whoever.

A.
 
Moisture meters are NDT but as for things like X ray, the issue is cost vs boat value for one, practicality for another ( just how would you Xray a hull?), and necessity since the average boat is hardly either high tech or highly stressed. Ultrasound is used on some metal hulls but on GRP I would have thought it would be useless because of inbuilt variability.

Would you use such techniques buying a second hand car? If not, why on a second hand boat?

P.S. I worked in an industry where there was extensive use of NDT so I'm familiar ( if a bit out of date) with the real life practicalities
 
GRP is inspected by ultrasonic NDT. The processing of the data produces quite clear pictures of the material and any defects. Examples below: -

http://www.ndt.esrtechnology.com/noticeboards/mms15iag/ikb/Browse/Default.asp?ST=1&SC=2&S=23
http://www.ndt.esrtechnology.com/no...ics/Introduction/UB+Introduction/Default.html

Time of Flight Diffraction is exactly the same as the seismic surveys that my teams take of the earth to establish where we want to drill for oil and gas. Over the years we moved from simple contour type maps (where the contours are returned signal times) to full 3D (and 4D now) detail. It is now possible to see all sorts of faults and hidden formations that were never visible about 15 years ago. I would assume that a certain amount of cross industry discussion and scaling of technology would naturally happen.
 
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