Prefabricate steel structure Workshop GAS sheielaed are welding welding wire flongation the welding wire elongation relates to the wire diameter,the welding electric current and the welding voltage. during the welding process,the distance between contact tube to the base material is generally as 10-15 times as the welding wire diameter. wire electric current stick up the principe that base materials are in the well welding penetretion,welding current should be accurately selected in accordance with thickness of base materials,joint type and the wire diameter. the range of welding electric current in common use variety of variety of welding diameters shown in table A2 diameter 0.5 0.6…