Dissimilar Metals, Specifically, A36 to A7 steels

By bullet Date 08-24-2015 13:06

We have to weld electrical support brackets with a fairly low overturning moment to A7 plate girders, The new brackets will be fabricated of A36 angles.What is the proper procedure, electrode, heat setting etc. to get a successful weld with good penetration. The plate girders have 3/8" webs and the brackets are L3x3x 5/16" Welds will be done vertically and are near side/far side detail.

By 803056

Date 08-24-2015 22:08

Difficult to predict until you have a chemical analysis for the A7 that is to be welded. They didn't control carbon, sulfur, or phosphorus back then. There was no need to control those elements because they were either bolted or riveted.

Al

By Len Andersen (***)

Date 08-30-2015 14:34 Edited 11-24-2015 16:14

Ladies and Gentlemen,
Worked with A7 as NYCDOT employee until out on my head for excess honesty ! My guess is 7018 SMAW with 250 preheat and welder doing in out of puddle technique. Said steel is over 100 years old without concern about preheat. The light loading mentioned and chemistry is concerns.
Sincerely
Len Andersen Engineer Member ASME IGTI
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