D1.4 question?

Date 01-13-2009 19:38

Hey guys heres a question just for fun.
Given: the ambient temperature of the base metal is approximately -18 C. the rebar to be welded is a #9 bar. The carbon equivalent is known to be 0.55. what is the minimum allowable preheat temperature need to weld this bar?

By jwright650 (*****)

Date 01-13-2009 20:07

Hopefully someone with a newer D1.4 will chime in but in my 98 edition Table 5.2 it says in Note 2 that welding shall not be done when the temp is BELOW -18C, you are right there, so make a judgement call on that one....and for #9 w/ .55CE it has 200F/90C listed as the min preheat.

By swnorris (****)

Date 01-13-2009 20:16

My 2005 states the same.

By jwright650 (*****)

Date 01-13-2009 20:39

Thanks Scott

By clutch

Date 01-14-2009 02:57

I was thinking along the lines of a trick question. assuming the base metal is below 0 then the atmospheric temp is the same and therfore welding is not allowed. So your right on!

By 803056

Date 01-14-2009 20:09

If you can enclose the area in a shelter so the ambient temperature can be rised, the preheat listed is fine.

Best regards - Al