Alloy & Non-Ferrous ASME vessels 1

[in43y]

Hi,
I work for a fabrication shop and we only make carbon steel pressure vessels to section VIII, Div 1. I have been there 4 years now, so I have a pretty decent understanding of the code. But now my boss tells me we might start doing high-alloy and non-ferrous vessels. If we do that, they will hire someone with experience in this area. But I want to be a little ahead of the curve and learn more about these since I'm sure I'll be involved too.
I am looking for some insight how high alloy or non-ferrous materials affect the design and fabrication process, compared to just plain old carbon steel vessels.
Any help is appreciated, thanks!

 

[ndeguy]

Hi in43y

Most important is total separation of stainless from carbon (I dont think its SO critical for high alloy but perhaps still a good idea). This means separate area, spearate tools - everything to avoid carbon pick-up.

 

[metengr]

The first thing I would do is if you have ASME Section VIII, Div 1 find Part UNF and review uses (UNF-3) and material sections (UNF-5), also find Part UHA, and review similar sections.

 

[Duwe6]

And if your fab people do contaminate your stainless by rubbing it over carbon steel items, as ndeguy is warning against, you will need to spot pickel/passivate those areas as they will rust forever if not removed.