Normalized, killed, or fine grain plate 1

[Heyner]

Hi everybody!

I'm not an expert formulating materials according applications, and I want to know the rules (if they exist) to know if a CS material (say SA516-70) must be normalized, killed, fine grain, and so on.

Other question, I want to understand how can I use A516-70 instead of SA516-70...

For instance, the vessels I'm working on are:

Hor Vessel ID=84" L=20', P=320psi, T=250°F
Ver vessel ID=84" H=100', P=300psi, T=279°F

Any help will be appreciate...

Heyner

 

[metengr]

Ok, first we must start with having you review the specific ASME SA material specifications - namely SA-515 and SA-516. These can be found in the ASME Boiler and Pressure Vessel Code, Section II, Part A (ferrous materials) and are unique to intended service conditions for the pressure vessel plates.

Both of these ASME B&PV Code material specifications address melting practices and heat treatments. They are self explanatory.

 

[Heyner]

Great, Metengr, I get it.

I'll see what I can find, and ask again if further help needed.

Thanks a lot...

Heyner

 

[JStephen]

Check with your plate supplier on some of those issues as well. For example, I think most of the modern plate is killed and fine grain, even though it may not say that on your PO. Normalizing is definitely an extra, though.

SA-516 should be essentially the same as ASTM A516. Check with your supplier to see if it meets both specs.

I don't know about ASME work, but in my field the normalized plate is usually required for low design temps or unusually thick plate.

 

[deanc]

Read the Forward in any ASME Code book. Think that will explain most of your basic questions.

 

[Heyner]

Ok, I found in ASME BPVC (SA-20 cause SA-516 address to it) the mandatory requirements, and what to do if normalizing is needed.

But my question is How can I be sure I need (or I don't) normalized plates? Is it like JStephen said, at low temperatures? Is it only one of the reasons?

Thanks for your help,

Heyner

 

[metengr]

For plates 1.5" an under, they can be supplied either hot rolled or normalized and stress relieved. IF notch toughness testing is specified by the Purchaser (you), the plates will be normalized per SA-516 (read 5.3). Plates over 1.5" in thickness must be supplied in the normalized condition per SA-516.

For low temperature service, I would prefer normalized plates because of the benefit in having higher toughness at low service temperature. Impact test requirements for your design will determine if you need to use normalized plates versus hot rolled.

 

[Heyner]

I see, think it is the key: service temp.

Thanks,

Heyner