A36 normalized steel ? 1

[fedeghi]

Hi there, this is my first post here!
I have been digging in the search results for a while, but I could not find what I'm looking for, so here I am.

I'm dealing with MDMT issues, and so I have to find the exact reference on ASTM standard, stating that A36 can (or cannot?) be normalized.

On paragraph 6 of ASTM 36 it is specified that A36 can be supplied also as semi-killed or killed steel... but what about a "heat threatment" paragraph (similar to paragraph 5 of ASTM 516..) ?

The problem is that, according to UCS-66, each non-normalized carbon / low alloy steel belonging to Curve A, when normalized, shall be grouped with Curve-B materials (except for some exceptions ), thus taking an advantage on the resulting MDMT.

Now I believe that A36 can not be normalized, but the problem is that I'm using a commercial pressure vessel software that on the contrary allows me to include A36 in UCS-66 Group B materials..

So, I'm quite confused. Anybody can help me on this topic?
Thank you, CIAO !

 

[metengr]

A36 is not supplied in a normalized or normalized and tempered condition. It can be supplied in a fully killed condition resulting in a finer grain structure, but that is it and it must be specified by the Purchaser.

Also, it is not permitted for use in Section VIII, Div 1 as A 36, this material would need to be certified as ASME SA 36 and follow the useage requirements in UCS-6.

According to UCS-66, SA 36 would fall under Curve A.

 

[SnTMan]

fedeghi, you should review UCS-6 for use of SA-36.

It may or may not be practical, but PWHT when not required by Code can get you a 30 deg. F MDMT reduction, see UCS-68.

Regards,

Mike

 

[stanweld]

fedeghi,
Why would you design a vessel using SA-36, killed with fine grain melting practice when you could use SA-516 Gr70 and take advantage of the higher Code design allowables and greater temperature range?

 

[fedeghi]

Stanweld, I agree with your suggestion: we are actually using Sa-516 Gr70 for each "plate-shaped" details, such as shell courses and bended profiles.

The problem is that some reinforcing external profiles (L shaped, C shaped and IPE profile) should be bended and welded on-site, because some big vessels will be assembled on site.
We wanted to have an easy site assembly solution, thus avoiding to manufacture the C shapes in field...

At the moment we have decided to manufacture as much as possible with 516Gr70, but it would be nice to find an alternative solution...