RT for socket welds

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Is anyone familiar with the radiographic testing of socket welds? Can someone give me some details? Thank you
Reply:It is a fillet weld. Proceed as such.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:What industry are you in? Is this just for qualification purposes? We xray many pipe butt welds, but none of our socket welds get xrayed. They do get other methods of NDT, though.Rich
Reply:I get socket welds x-rayed and we weld under ASME code. We also get O-lets shot as well. The are mostly looking for gap and and any inclusions or porosity, but have also seen folks get called for lack of fusion with TIG roots. We have mostly been doing fusion welds with TIG very hot for the first pass to avoid any issues.I hear that its not common to RT socket welds, but we do at good old Shell oil.
Reply:Originally Posted by weldwebIs anyone familiar with the radiographic testing of socket welds? Can someone give me some details? Thank you
Reply:Main thing is the gap, anything else is gravy. If you jam those up, they can fail in a hot service when things expand.
Reply:Originally Posted by TimmyTIGMain thing is the gap, anything else is gravy. If you jam those up, they can fail in a hot service when things expand.
Reply:ASME code? Section III and VIII both require surface exams for socket joints. Not sure what ASME code requires RT on socket welds? B31.1 is typically a visual for most joints. We have recently RTed and distructively examined a few socket welds just for interest and what found a few interesting flaws. The power industry is starting to require 2 to 1 tapers in order to reduce the geometric stress riser of a socket weld joint design. Many powers plants have had power outages due to failed socket welds over the last few years. I would expect some owners to elect for RTs as a way to avoid failures of critical joints. Hardest part would be to get the density of the RT to meet code requirements due to the material thickness differences or in RT words, the latitude of the joint. May need to double load the film with different film speeds to shoot the joint.
Reply:All our socket welds are visually examined, then LP (liquid penetrant) tested.For test qualifying purposes, they are also cut in half lengthwise, polished, then macro-etched and 5X examined, in addition to VT and LP.And speaking of gaps ( or "the pull" as we call it), that is so that during welding, if shrinkage causes the pipe and the socket to contract towards each other, the fitting won't crack.RichLast edited by steelsurgeon; 06-21-2015 at 08:30 AM.