PASS/START-PROF calculates the Minimum Design Metal Temperature per ASME B31.3 para. 323.2.2 (a), (b), (d), (e), (f), (g), (h), (i), and (j).
The minimum temperature values come from the material database. When a curve type is specified, the program determines MDMT from the diagram below based on component wall thickness.
Per ASME B31.3 323.2(g), when you enable "Use MDMT Allowable Reduction" in project settings and the stress ratio r < 0.3, MDMT defaults to -104°C (-155°F).
Per ASME B31.3 323.2(h), with "Use MDMT Allowable Reduction" enabled for carbon, low alloy, or intermediate alloy steels, PASS/START-PROF reduces MDMT according to Figure 323.2.2B. The reduced temperature cannot drop below -48°C (-55°F) for base metal or -29°C (-20°F) for weld metal. The program automatically calculates stress ratio "r" from all operating cases per 323.2.2(b).
After analysis, the report shows "Impact Test" if the minimum design or ambient temperature from any operating case falls below the calculated MDMT. It shows "OK" if temperatures remain above MDMT.
After analysis: Output > MDMT, Impact Test