Addendum: weld guys get nervous cause if they use too hard enable weld rod, too high heat input, and don't pre and post heat, their welds can crack with the higher thermal cycling with wrapping.
All this means is they don't want to control their welding processes and materials consistently, or want a common weld rod for all their work.
Back to original point - the steel tubes don't care - the welding has to be done correctly not to have a hardenable weld joint prone to thermal cycling cracking.
We now take you back to your normal program with
@Wild one