Ductile Iron pipes to Lugs (made of Ductile iron) standard cooling rate after welding

[hashanw007]

HI,
I need to know the standard practiced cooling rate for welded joints (Ductile Iron pipes and Lugs) I could find some information that says air cooling is better,However my senior engineer wants to be able to prove it. ie, it has to come from a reliable source. I tried hard but couldn't really come up with a standard. It would be great if any of you guys could help me out with this.
Thanks

 

[arunmrao]

You may find the link helpful.

Field welding and cutting Ductile Iron pipe.

http://www.dipra.org/publications/guidelines.cfm

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