Dear Experts,

As we know,Only the minimum preheat temp is specified in the WPS,however QC personnel found that the actual preheat temp. exceeds the max. interpass temp.during the welding, is that acceptable? BTW,the WPS referred have the toughness requirement.

Thanks for your advice!!!

This is a very strange sounding situation and more information is necessary to give a good answer. What is the material type, preheat minimum and interpass maximum? Also useful but not necessarily required, what constructing code?

An immediate answer seems to be "no, this is not okay" but it sounds like something may be wrong with the maximum interpass???