root cause for failure of bend test
root cause for failure of bend test
(OP)
Hello,
what is possible root cause for failure of bend test from haz(crack parallel to weld seam).
bend sample taken from tranverse to weld seam in api 5l x52 material..
what is possible root cause for failure of bend test from haz(crack parallel to weld seam).
bend sample taken from tranverse to weld seam in api 5l x52 material..





RE: root cause for failure of bend test
Please can you give a lot more information about the failure at present the failure could be a multitude of things of which the following list is not exhausted:-
Hydrogen embrittlement
weld porosity
lack of fusion
weld inclusions
incorrect post or pre heat treatment
incorrect filler material
incorrect settings of weld parameters
A picture of the failure also might help you get some proper answers
RE: root cause for failure of bend test
RE: root cause for failure of bend test
RE: root cause for failure of bend test
If so, you can rule out:
Hydrogen Embrittlement (if you have hydrogen problems, you have a base metal problem and the integrity of the weld isn't going to matter)
Weld Porosity (If there in porosity in an ERW weld, again, it's a base metal problem, not a welding problem)
Lack of Fusion (ERW is a non-fusion process; there is no fusion, so it can't be lacking)
Incorrect filler metal (as with the fusion; hard to have incorrect filler when there is no filler metal)
That leaves:
weld inclusions (could show up as hook-cracks; check silicon content and weld pressure)
incorrect pre/post heat (in particular normalizing of the weld seam and cooling afterward)
incorrect weld parameters
and, not mentioned
improperly prepared faying surfaces (dirty, contiminated, or unsuitable geometery).
rp
RE: root cause for failure of bend test
we are using double side welding by tandam arc saw , woldwide used for manufacturing of line pipes as per api 5l LSAW PIPE.
before cut bend sample rt was clear,
pipe size: 18"X17.50mm
grade: api 5l x52mo
hardness come in haz area was max 200hv10
RE: root cause for failure of bend test
RE: root cause for failure of bend test