UT minimun thickness UT minimun thickness Joss10 (Mechanical) (OP) 14 Mar 17 21:07 Dear all, My contractor is telling me that conventional UT examination is not feasible on piping welds less than 9 mm. thickness. Is that right? Thanks for any input. RE: UT minimun thickness SectionIX (Petroleum) 15 Mar 17 09:30 Probability of detection is dependent on several factors including but not limited to material type, thickness, outside diameter, welding process, expected imperfections, Code/specification acceptance criteria, ultrasonic shear wave/PA equipment, and technician experience. I don't agree with the contractor, however, you didn't state the application. I would ask them for an explanation. RE: UT minimun thickness brimmer (Petroleum) 15 Mar 17 16:08 WTF??? Your contractor is out to lunch.... Most of the pipelines I'm involved with have a wall thickness less than 9mm, but yet we do UT everyday on the welds... Get another contractor, one that is competent, without knowing all the details here... RE: UT minimun thickness DekDee (Petroleum) 16 Mar 17 02:39 The contractor has said it is not "feasible" - they have not said it is not possible. UT under 9 mm thickness is performed daily all over the world. However, some codes require special procedures to be qualified for 8 mm and under and maybe the additional time or cost of developing these procedures leads the contractor to state it is not "feasible ? Cheers, Shane RE: UT minimun thickness Joss10 (Mechanical) (OP) 16 Mar 17 09:15 Dear mates, Allways keep in mind are talking about "conventional UT", neither phased array nor automatic or whatever more sofisticated. Thanks for all input. RE: UT minimun thickness metengr (Materials) 16 Mar 17 15:48 Keep in mind that Section I of ASME B&PV does not permit UT below 1/2" thickness. Also, keep in mid a code case was passed to allow the minimum thickness for UT to 1/4".