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Re: [MW:12942] Pre heating

By Materials & Welding
Good day Ramana,
after root pass has been finished, the weld shall not be allowed to fall under room temperature. What you need to do is to keep temperature between first and next passes. This is always associated with metallurgical structure. I suggest you to proceed with the new.

Rgds

2011/11/10 venkat ramana <venkatgps.ramana@gmail.com>


Dear All,

While welding of ASTM A335 Gr P11, what to do if welding was stopped after Root 
Pass ,Hot Pass and One Fill-Up done without completing the job? Can we do immediately Post Heating for the un-finished job and continue welding next day? or Should we cut and re-weld the joint?

I have one more doubt... In the above situation what if welding and Pre-heating(coil heating) was stopped due to power failure for 2 to 3 hrs and the joint has to come to room temp. Should the joint be cut and re-welded?

Regards
Venkat (QC Inspector)
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