One-metre-long seam welding of aluminium sheets by applying magnetic pressure: introduction of new connection method of long sheet metal ends

Thin aluminium sheet, which is characteristically light and has high strength per unit weight and good workability, is widely used in, for example, industrial products, household products, and soft drink cans. In a production line capable of continuous surface treatment and heat treatment of thin aluminium sheet, it is necessary to join the rear end of the preceding aluminium sheet to the leading end of the next aluminium sheet coming onto the line. There are various methods of performing this joining technique, which is known as ‘sheet connection’. In many cases, the ends of the sheets are brought to a temporary halt to be joined. Electromagnetic seam welding – 8 is used for sheet connection and this has the extremely short welding time of 10ms. Here, we report on basic experiments in electromagnetic seam welding of long aluminium thin sheets of 1 m or longer, on various sheet connection methods, the fabrication of connections for experimental line treatment and, finally, on a new sheet connection method.