Using 316 electrode instead of 309
Using 316 electrode instead of 309
(OP)
I am working in a company which makes valves for sour gas. In our procedure we have to use 309 electrode as a buffer and 316 electrode for the final but the sub contractor has made a mistake and they used 316 for both layers. The final composition is in the range and no cracks were observed and the bending tests for 316/316 were also accepted. I want to know what I have to do for these overlays, are they acceptable, is it necessary to do any other test and …. I appreciate any helpful ideas and opinions





RE: Using 316 electrode instead of 309
RE: Using 316 electrode instead of 309
RE: Using 316 electrode instead of 309
In long term at high temp C will diffuse more rapidly through 316 than through 309.
316 may (depending on chemistry) be more prone to formation of detrimental secondary phases (sigma).
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Plymouth Tube
RE: Using 316 electrode instead of 309
If the external weld overlay meets the chemical requirement for 316 stainless, sigma formation will not be an issue. Sigma is going to happen throughout the entire overlay because the material originally selected was 316.
RE: Using 316 electrode instead of 309
RE: Using 316 electrode instead of 309
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: Using 316 electrode instead of 309
RE: Using 316 electrode instead of 309
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Using 316 electrode instead of 309
Having used 309L electrode in the first layer, martensite phase was also formed (according to my experience) near HAZ. However, after welding the second layer this phase could be tempered. Since the bending tests met the standard requirements, I think mechanical testing and martensite are not the main concerns.
RE: Using 316 electrode instead of 309
RE: Using 316 electrode instead of 309
then re-weld a new section is slightly longer to allow for weld shrink & parent material consumed.. This a standard repair when the weld is FUBAR, and not repairable. Eliminates if this is issue or not.
Mfgenggear