[charlie]

AUT tends to focus more on the bevel sidewalls as compared to RT which wouldn’t miss a 3mm Pore that AUT at times might. Both the techniques have their own advantages and disadvantages and shouldn’t be compared. Both the techniques use API 1104 for evaluation again which are basically the same. I unfortunately haven’t had the chance to work with RT and I wouldn’t be able to answer all of your questions I’m sorry.

I would recommend AUT when it comes to long pipelines, the primary reason being that if you’re running a semi automatic / automatic welding mainline setup, your biggest concern would be production in which case AUT would give you more real time results in the sense that the AUT crew would be just beyond the mainline most of the time. You can even have the welding crew informed beforehand as well for certain indications that keep repeating themselves at particular locations, the welders and the on site technician would be more than willing to fix it once you give them the depth, the location and the height and they figure out which pass it comes from. You can also have a repair crew run behind the AUT crew to fix the repairs immediately. Overall this kinda setup usually works out very well for everyone.

I hope this helps.