A Structural Welder joins metal components to build or repair large structures like buildings, bridges, and pipelines by cutting, shaping, and welding metal according to blueprints and specifications. Key responsibilities include preparing metal, operating various welding machines (MIG, TIG, stick), inspecting welds for quality and safety, maintaining equipment, and adhering to strict safety regulations. They are essential for ensuring the strength and safety of structures, often working at heights and in collaboration with other construction trades.