transition temperatures for a312 stainless

[sftyvlv]

Where can I find transition temps for a312 in the code books.
I'm just starting as a level 1 welding inspector,QC (Canada) and just learning.
Thanks
Sftyvlv

 

[metengr]

I believe you are referring to 312 stainless steel weld filler metal rather than an uncommon grade of wrought 312 stainless steel. The 312 stainless steel filler metal composition because of the rather high chromium content solidifies as a two phase structure - ferrite and austenite. This is needed for dissimilar metal weld combinations and for cast stainless steel alloys of similar composition as the 312.

Because this filler has a significant amount of ferrite, the impact transition temperature will vary and is not reported in Code books. However, ASME Section VIII, Div 1 does provide some guidance relative to low temperature service and cryogenic service and impact testing requirements.

This filler metal would be limited to the impact test requirements in UHA-51 of ASME Section VIII, Div 1.

 

[sftyvlv]

Sorry Metengr, what I ment to say was A304 pipe. I thought a312 was the material group and covered a304 (304 being the grade).
Thanks
Sftyvlv

 

[MikeMet]

There are no transition temperatures in the "Code" books. Go to the ASM Metals Handbooks or an ASM Book on phase diagrams for different materials.

 

[vesselfab]

i was under the impression that A-304 was a bar specification/

are you sure you are not talking about A312-TP304 & A312-TP316 or some other tubular product?

 

[sftyvlv]

vesselfab I believe you are correct, it is a312-tp304.
thanks
Sftyvlv

 

[metengr]

sftyvlv;
Type 304 stainless steel does not have a ductile to brittle transition temperature so you will not see one published code books or otherwise. Type 304 and other austenitic grades of stainless steel can be safely used down to -320 deg F and even lower because the predominant stable phase in these metals is austenite.

 

[sftyvlv]

On welding pipe made with this material, what would should my interpass temperature be?
sftyvlv

 

[metengr]

300 deg F max.