When welding pressure vessels, required preheat and PWHT are specified on ASME VIII. When welding piping, required preheat and PWHT are specified on the appropriate section of ASME B.31.
Giovanni S. Crisi
Sao Paulo - Brazil
Prof Crisi,
True, maybe he needs the pre heat information for WPS preparation.
ASME recommends metals should be heated to a temperature at least warm to the hand [estimated to
be above 60°F (15°C)] before welding is started.
Regards
Joey
Dear
You have preheat calculator with Hydrogen Control method for example or IIS for determiner minimum preheat
In ASME section VIII Div 1 Apen. no mandatoy R suggested preheat for Pnumber.
But you have the calculate minimum preheat.
AWS D1.1 have a excellent method for determiner preheat.
DAYANARA
ASME Section IX does not have a Table as you intend. This is because ASME Section IX is not a specific code of construction.
ASME Seciton IX addresses general qualification requirements.
Specific preheat requirements will be specified in the codes of contruction such as Sections I, VIII, 31.?, etc.