pre heat 1

[EngrRodri]

Mates.
Good day1
Please inquire how to calculate pre-heat temperature using only CE value regardless of thickness.
Any references in ASME can be use as guide or other particular book.

Thankyou

 

[metengr]

Preheat temperatures are listed for guidance in various ASME Boiler and Pressure Vessel Code book sections (I, IV, VIII), also in ASME Piping Codes. They are based on base material grouping. You don't need any calculations.

 

[weldstan]

Minimum preheating temperatures are also provided by piping Codes like B31.3.
Preheat requirements are not only a function of base metal C.E., but also the welding filler metals' composition, welding process (low hydrogen), and thickness welded.

 

[gtaw]

I often refer to Annex I in AWS D1.1. It is a rather conservative approach that takes into consideration the chemistry of the base metals, the level of hydrogen control exercised, the thickness of the base metal, and the degree of restraint. The resulting preheat is typically higher than that required by ASME construction codes or NAVSEA fabrication standards.

Best regards - Al

 

[EngrRodri]

Thank you mates..

@ gtaw (Structural)
in AWS D1.1 TABLE X1-2 & X1-1
only the CE is up to .38, however the still it lack
because my CE value is 0.46

@ weldstan (Materials
my smaw will be E7018-1H4R


@ metengr (Materials
Because most of new materials encounter in this project they used is non listed in material grouping. I don't know why is this project is stressing a lot

 

[metengr]

Fair enough, If that is the case, there are tables where the CE range is provided and a recommended preheat temperature is provided;

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