It will be suitable if the RS is evaluated not only near the weld but also on the opposite site of the pipe.
Thank you for the responses. Can you suggest some paper dealing about this?
Measuring residual stresses is challenging, and no one method is best. This community can probably give a better answer if you provide more information. How big is the pipe: diameter and wall thickness? By "opposite side" do you mean on the inside of the pipe? That is a challenge but maybe possible. Why do you want to know the residual stress? The optimal measurement can be different if you want to predict stress corrosion cracking or distortion, for example.
Diameter of the pipe is 1m and the thickness is 12mm. Yield stress is 500MPa. Sorry for confusing usage of "opposite side", I mean the place far from the weld(let´s say 20cm and more). The pipe was not used I am just comparing different measuring methods and evaluation techniques.
OK, a big pipe and not very thick. As others have mentioned, X-ray diffraction is one possibility. There are portable instruments that could be used on such a specimen. X-ray sometimes has difficulties with some steels and with weld metal, but there is a reasonable chance it would work. X-ray will give you surface stress. With electrochemical material removal and careful work, you could get a depth profile.
Other non-destructive techniques, like magnetic and ultrasonic, are much more challenging to apply in an accurate, quantitative way on such a specimen.
On such a large specimen, it would also be common to use hole drilling (or ring core), which could give you a depth profile of stress at multiple locations. Of course, that will leave behind a small hole, which may be an issue. Some people do that and fill the hole back in.
More sophisticated approaches are possible. Deep hole drilling can and has been done on large specimens like that, and would give you through-thickness stresses. At only 12 mm thick, you could penetrate that with neutrons, and there are a couple places that could probably handle something that size. Those measurements could be free at a user facility if you plan to publish the results.
Best of luck.
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