|Thank you to Ed Ginzel for posting at Aug-31-2015 the following topic to the forum.
About 2-3 weeks ago, one of the forum members sent me email asking me about the topic of PAUT focussing. It seems that he was at a well-known training school and the instructors there told him that he should be focussing the beam for weld inspection. No doubt he had to do this to pass the course, but it did not seem right to him so he asked me for my thoughts.
I used Civa to explain why it should not be done.
The idea that training schools are telling students to do things that are not accomplishing useful results bothered me so I thought it might be helpful to put a discussion topic out to NDT.net, with some extra details (with thanks to Civa for making the explanation much more "visual").
Perhaps typical of my explanations, the item is rather long, so not suitable to fit in the normal sized discussion box. Therefore I have uploaded the thoughts as a pdf file. To Focus or Not to Focus
|Read the Discussion in the Forum|
I would be interested to learn of other people's experience with focussed beams for general weld inspection (apart from the zonal technique).
Materials Research Institute