minimum welding temperature??

By dee

Date 10-10-2002 19:19

Are you asking if the temperature should be below or above the liquidus temperature of the material being welded?

Give us a little more information and we may be able to help

By Niekie3 (***)

Date 10-10-2002 19:25

When welding steel, the minimum temperature is around 1600°C. This is approximately the temperature at which steel melts.

I do however believe that you are not looking for the welding temperature, but probably the pre-heat temperature. Am I right? If so, we need some more info like:

1) What material?
2) How thick?
3) What welding process and filler?
4) What service? (e.g. fatigue, Stress corrosion cracking service, Impact service)
5) Is the question aimed at the interpretation of code requirements? If it is, what code?
6) Is the question aimed at preventing hydrogen cracking?

We really need more info to answer this question.

Regards
Niekie

By kevinlindsey Date 10-10-2002 19:28

We have a contractor who will be welding a steel post to a 1 1/4" thick steel base plate. The work will be during the winter months in TN. We had concerns with cracking.

By jwright650 (*****)

Date 10-10-2002 20:35

Follow the Table 3.2 in AWS D1.1:2002 and match your materials in the group Categories ie. A, B, C and D and on the right hand side of the chart are the thicknesses and preheat temps you are looking for.

ie. Category B
A36 mild steel >3/4"; SMAW w/ low hydrogen rods; material thickness over 3/4" thru and including 1 1/2"; minimum preheat and interpass temperature is 50 degrees F.; and the interpass temp. shall be maintained during welding.

Hope this helps

By kevinlindsey Date 10-11-2002 13:39

thankyou, yes this helps a lot

By kpauley (*)

Date 10-11-2002 14:00

Don't forget about the "Zero to 32 Degrees" clause.

By jwright650 (*****)

Date 10-11-2002 14:27

You're right, I failed to mention section 5.12.2 AWS D1.1:2002. (Also see C5.12.2, for the commentary on this section)
Thanks kpauley, I didn't mean to mislead anyone.