Production of double finned tubes by resistance welding - has spaced tubes inverted intermittently to exchange positions for successive weld stages

摘要

The production of double-lined tubes is carried out by electrical resistance butt-welding at the fins. The spaced tubes are arranged parallel to each other and held above each other. They are turned through 180 deg. about the centre of their connecting line after a given number of welding operations, so that the tubes exchange positions. There is a transport table which moves with the stroke of a welding machine. A rotatable tensioning device is arranged at both ends of the table. This table holds the tubes to be finned at equal spacings from the axis of rotation. The tensioning device drives are produced synchronously by motors which are operated via an adjustable counter from the stepping equipment of the welding machine.