This requirement is for three mobile, engine-driven welding machines and three trailers, capable of performing Stick, MIG, flux-cored, and DC TIG welding without manual reconfiguration. The systems must provide simultaneous weld output and high-capacity generator power (12,000 peak/10,000 continuous watts) without derating, and support air carbon arc gouging. The welders must be diesel powered. No timelines, budget amounts, or performance location are specified in the description.