Enter the allowable stress for the element material at operating temperature. The operating temperature for most vessels is defined to be the same as the design metal temperature for the internal pressure. You can find this value in the ASME Code, Section II, Part D, Table 1A, 1B, and 3.
If you enter a valid material name in Material Input, the software searches its database, determines the allowable stress for the material at ambient temperature, and populates this field.
The software also determines the allowable stress when you select a material name
from the Material Selection window.