Steam line noise found

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For the guys that work in the steam and power industry this may be informative.  This will probably make no sense to others.  For about a week we have has a noise in a condensate drop leg off of a 24" steam line.  The drop leg is on a 150lb. extraction line, down stream of our turbine and after the isolation valve and non return valve.  The noise sounded like steam being injected under water but the line was empty.  We waited until the weather was going to give us a day with the temps above freezing so we could shut the plant down and figure this out.  After cutting an inspection hole the source of the noise was easily found.  Pictured is a 2 1/2" fine thread nut that was laying in the bottom of the drip leg.  After looking at the drawings of the non return valve we are very sure that the nut held the valve disc to the swing arm.  The picture of the torched disc is what the inside of the pipe looked like.  A very nice looking hammered finish.  After doing UT testing on the pipe, everything was ok to put back together.  Contractors put a patch in and we started back up.  Took the about two hours after issuing lock out and work permits for the job.  Heating the plant back up was a different story.Sorry no action welding pictures because the area where two guys were working was very cramped and they stayed in there until they were done.  Not sure on the steel make up or type of rod used.Dan D. Attached ImagesManipulator Of Metal
Reply:I bet everything is nice and quiet (for steam) after taking that thing out. Was there something attached to the edge of the nut? I also noticed decimal numbers on the pipe and patch, is that the material thickness and are you required to write that down when a repair is made?TOO MANY TOOLS & NO MORE SPACE
Reply:Originally Posted by Chris T.I bet everything is nice and quiet (for steam) after taking that thing out. Was there something attached to the edge of the nut? I also noticed decimal numbers on the pipe and patch, is that the material thickness and are you required to write that down when a repair is made?
Reply:I used to do mechanical piping and we often worked in places with steam. Absolutely amazing how abrasive steam can be, used to see holes in 90's and it would find its way out of valves.TOO MANY TOOLS & NO MORE SPACE
Reply:makes sense to me. that must have made some racket bouncing around in the mud leg.i.u.o.e. # 15queens, ny and sunny fla
Reply:Was this in an awkward place to weld? It's a little hard to tell in the picture but some of that weld doesn't look that great for being a pressure weld.
Reply:That whole deal doesn't look kosher to me.Cut a hole in the pipe, then weld a patch in? On top of an existing weld to boot. And what's going on with that end cap?
Reply:If the QC guy ok'd it,  you have no worries.  It's much less costly than removing a complete section of pipe. The writing on the cap/patch is the wall thickness that the UT guy determined after testing.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:A leaking 1" weld o let determined where they cut the hole. They had about 10" of room between the patch location and three condensate lines.  The QC guy watched the entire job.  I am not sure if the patch was rolled or taken from another pipe.   The end cap is on the bottom of the drip leg.  Not sure why it looks budged but it's not. There was no good place to get my phone camera for a proper pictureLast edited by DanD78; 01-19-2015 at 09:42 AM.Manipulator Of Metal