Bending Electric Fusion Welded Pipe
Bending Electric Fusion Welded Pipe
(OP)
Should I avoid bending EFW pipe and strictly use fittings? If it's OK to bend EFW pipe, what precautions should be taken versus seamless pipe? Does it matter if the weld joint is along the side of the bend or on the inside/outside of the bend? Any help and experience with this is greatly appreciated.





RE: Bending Electric Fusion Welded Pipe
Steve Jones
Materials & Corrosion Engineer
http://www.oilandgaspeople.com/cv/11499664
http://www.linkedin.com/pub/8/83b/b04
RE: Bending Electric Fusion Welded Pipe
RE: Bending Electric Fusion Welded Pipe
"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.liv
RE: Bending Electric Fusion Welded Pipe
RE: Bending Electric Fusion Welded Pipe
RE: Bending Electric Fusion Welded Pipe
"We have a leadership style that is too directive and doesn't listen sufficiently well. The top of the organisation doesn't listen sufficiently to what the bottom is saying." Tony Hayward CEO BP
http://www.youtube.com/watch?v=hpiIWMWWVco
"Being GREEN isn't easy." Kermit
http://virtualpipeline.spaces.liv
RE: Bending Electric Fusion Welded Pipe
You can check ASME B31.3 - chapter V - parag. 332 (Bending and Forming).
As BigInch said you should avoid put the longitudinal weld joint in the intrados or extrados of the bend.
RE: Bending Electric Fusion Welded Pipe
The intrados and extrados are going to be max plastic strain but on either side of neutral axis (NA) is going to be max residual stress since the NA doesn't change length. As you move farther away from the NA the material yields and this will limit residual stress after the pipe is released from the bend machine. The areas of high residual stresses will be more susceptiple to corrosion and that might have been the reason to avoid the NA.
Increased ovality will also drive hoop stresses up and it could have been a reason that the NA was also identified as a location to avoid with the weld seam on a bend.