ASME 2011A section II-D table 1A General Notes(e)

[Tony1t]

Hi everyone,
ASME 2011A section II-D table 1A, General Notes(e) said that Stress values for −30°C to 40°C are applicable for colder temperatures when the toughness requirements of Section III, VIII, or XII are met.
If impact test is exempted per ucs-66,ASME SECTION VIII-1, is't need still to do impact testing for the material? thks!

 

[RTSRI]

Hi Tony
this is my interpretation:
In general Tensile and Yield strength increases at lower temperatures, this is characteristic of metals and alloys.
At low temperatures your main concern for safety is brittle fracture.
So if your design conditions allow UCS-66 impact exemption, your design sattisfies the safety requirements of the ASME VIII Div-1, regarding brittle fracture and therefore no additional tests for allowable stress values is required. The table 1A values specified for -20 to 100 F can be used for strength calculations
See also BPVC UCS23 of section VIII Div-1