Pipe Distorted During Welding - How to Repair / Inspect?

[AeroAlx]

I have a 3" line that had some welding done on it, but now it appears that the piping had warped due to the welding such that the connecting joint centerline(s) are off about 1" from eachother, I believe to the side and a little bit to an angle.

What specifications or procedures are out there that can help provide methods for which to correct this to bring it back to where we want it to be?

3" Carbon Steel, A106-B or API 5L-B I believe.

Any help would be appreciated.

 

[BigInch]

Cut out and replace.

"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek

 

[Duwe6]

What BigInch said. At a minimum, cut the offending weld and refit & reweld it. But 3"NPS pipe is cheaper than Fitter & Welder time. Drop a new piece in [and think about getting a better Fitter].

 

[racookpe1978]

Draw your problem: The intended layout of the 3 inch line and the "as-welded" configuration of the 3 inch line.

"Simple distortion" of the 3 inch line is unlikely to "move" the pipe that far from where it was welded, BUT (big but there!) a long 3 inch dia pipe stub welded at one end "might" see that 3 inch (small bore) pipe droop or move (if unsupported) at the far end (the open end) of the pipe.

As above, your fitter should know the movement of pipe ends from heat at the base point, and should have compensated for it. He (she ?) should also know the flexibility of pipe during assembly and should support both ends of his pipe during fabrication and cutting.

do NOT under ANY circumstances allow the pipe to be "kinked" if straightening is attempted.

 

[BigInch]

1" offset on a 3" diameter is way ,way too much to tolerate.

"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek

 

[11echo]

1" off on a 3" line? ...Sounds like the weld was not square to the pipe bore as apposed to any weld warp age. Replacing it is one option, how ever for expedience I'd look at "hot ringing" the pipe and bending it back in line.

 

[BigInch]

You'd better check on what repair methods your design code allows before things get too far out of hand.

"People will work for you with blood and sweat and tears if they work for what they believe in......" - Simon Sinek

 

[XL83NL]

To answer the poster's original question, you may refer to ASME PCC.
Although it may not be applicable 1-to-1 to new equipment [PCC-2 is for equipment after it's been place in service - I cant judge if your equipment is new or has been in service], some (major oil&gas) companies refer to it for e.g. pipe straightening, bending, weld defect repair, etc, also for new equipment. It contains some valuable info and techniques.

Now, given the quality aspect of the problem you're stating, I'd leave the solutions up to the experts, as posted above . Not having any thoughts on that ;-)