Preheat

Date 08-07-2009 13:40

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

By Joey

Date 08-17-2009 05:40

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

By DAYANARA (**)

Date 08-10-2009 04:00

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

By js55

Date 08-10-2009 12:50

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.

By ssbn727 (*****)

Date 08-16-2009 06:30

Hi Everybody!

Here's a preheat calculator for online use:

http://www.gowelding.com/weld/preheat/preheatcalc.htm

I also have one from lincoln electric which one can purchase through this site link:

https://ssl.lincolnelectric.com/lincoln/apdirect/item.asp?prodnum=WC-8

Respectfully,
Henry