Transition Temperatures

[MIMFFS]

Does anyone know the lower and upper transition temeratures for ASME P1 materials? Specifically SA-53 GrB
and if so where is a good place to find this type of info for future reference?

 

[metengr]

The transition temperature you mention is actually the ductile-to-brittle (DBTT) transition temperature for steels. The DBTT is either determined from actual Charpy V-notch impact testing of the product form or you can use ASME Boiler and Pressure Vessel Code, Section VIII, Div 1 UCS-66 Figure for exemption of impact testing. Curve A could be used for this material.

 

[MIMFFS]

I need the lower transition temperature ( The temperature at which austenite begins to form during heating) and Upper transition temperature (The temperature at whch transformation of the ferrite to austenite is completed during heating) sorry; my question may not have included the exact type of answer that I needed
Thanks

 

[chaulklate]

If it's the high temperature range of the material you are looking for relative to pressure, check Section II Part D. I don't have my copy handy right now, can't tell you specifically what page that would be on.

 

[metengr]

MIMFFS;
Ah, Ok, you need information on the lower critical transformation temperature. For P-No 1 materials, per ASME B31.1 (Table 129.3.2) use 1340 deg F.

 

[metengr]

For the upper critical, use 1550 deg F or higher, to assure formation of 100% austenite in P-No 1 materials.