They where all flat welds as this was a new bridge. We did repair some older bridges and there we had to weld out of position on most of those welds. These we usually used 9018 and 10018 3/16 rods. Set the welder usually at 175-200 amps.
When we where doing those flat welds they sure created some heat. I sure pitied anyone that had to do them in the summer. We where welding in the winter. You kept warm.