A "6G CS Welder" is a highly skilled welder certified to perform welding in the most demanding position, known as the "6G" position, specifically on Carbon Steel (CS) pipes and components, requiring precise control and adherence to strict quality standards, typically used in industries like oil and gas, where complex pipeline welding is necessary; their responsibilities include reading blueprints, preparing weld joints, performing welding operations in the 6G position using various welding techniques (like TIG or MIG), and meticulously inspecting welds for quality assurance.