SA-515 vs. SA-516
SA-515 vs. SA-516
(OP)
What is the difference between the two steels. Does one have a lower ductle-to-brittle transition temperature??
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RE: SA-515 vs. SA-516
Andy
RE: SA-515 vs. SA-516
RE: SA-515 vs. SA-516
RE: SA-515 vs. SA-516
ASTM A-515 Standard Specification for Pressure Vessel Plates, Carbon Steel, for Intermediate and Higher Temperature Services
ASTM A-516 Standard Specification for Pressure Vessel Plates, Carbon Steel, for Moderate and Lower Temperature Services
In ASME Section I (power boilers) A-515 can be used at higher temperatures that A-516 (1000 F vs 850 F). In Section VIII they have the same HT limit.
RE: SA-515 vs. SA-516
Please find at ASME Boiler & Pressure Vessel Code - Part A (Ferrous Material Spesification) table A1.15 for Minimum test temp. combination meeting charpy V-Notch requirements indicated. You can clearly see that the A-516 group is suiable for low temp. Please note that the A-515 group requires post weld heat treatment in order to avoid cracking.
RE: SA-515 vs. SA-516
RE: SA-515 vs. SA-516
2) The minimum Design Metal Temperature is 0°C (Design T.427°C Max.)as per our class.
3) According to ASTM A515 para.5 (2in and under in thickness mat be ordered normalized or stress relieved, or both).
4) Following to B31.3 Fig.323.2.2A (curve B) it is necessary to impact tested this material.
My question is: the material must be stress relieved or normalized.
Thank you for your help.
Ellynn
RE: SA-515 vs. SA-516
Plate material furnished under the ASME SA 515 specification is for use in components or vessels that operate above ambient temperature service because of the coarse grained structure of the material, resulting in lower impact or notch toughness properies. So yes, SA 515 plate material has poorer impact properties in comparison to SA 516 plate material, which is supplied as fine grained material. I believe the SA 515 pressure vessel plate specification replaced the original SA 285 plate specification that was used in many ASME Section I boiler components like waterwall drums, etc.
For vessels or components that operate above ambient temperature service, SA 515 is acceptable plate material because you would be above the ductile to brittle transition temperature in service. For vessels that operate at or below ambient temperature service, the SA 516 plate material would be specified because of improved impact properties or notch toughness per ASME Section VIII Div 1 or Div 2 mimimum design metal temperature requirements.
RE: SA-515 vs. SA-516
SA515 did not replace SA285. SA285 is alive and well.
Shmulik,
ASME VIII, UCS-56 covers PWHT for the P1 materials (of which SA515 is included) based primarily on a thickness criteria. P1 materials will require PWHT above 1.25 inches, unless preheated to 200F. PWHT is required for thicknesses above 1.50 inches. But, I do not recall any specific requirement that SA515 was singled out for PWHT as a Code rule. Where in the ASME Code does it say that SA515 is required to be PWHT other that when required based on thickness?
Steve Braune
Tank Industry Consultants
www.tankindustry.com
RE: SA-515 vs. SA-516
You are correct, it was SA 212 that I was thinking about not 285. That is what happens when entropy sets in after 40. By the way, I deal with NBIC/ASME issues, and I do not recall a similar requirement for PWHT of SA 515, other than PWHT requirements in accordance with UCS-56 or PW 39.
RE: SA-515 vs. SA-516
RE: SA-515 vs. SA-516