Longitudinal seam welding is one type welding process used to produce linear welds on a wide variety of parts. This process is used for many industrial applications to form the material into a desired shape (e.g. a cylinder or rectangular tube), by welding the abutting edges to form a rigid structure. The traditional method of doing this is to manually hold the edges in alignment, tack weld them and then complete the linear weld. This is done manually or by use of a simple carriage carrying the welding torch.
Longitudinally Finned Tubes provide 8 to 12 times the heat transfer area of bare tubes. It offers smaller exchangers due to increased heat transfer area. The fins are 'Cut & Twist' to increase shellside fluid turbulence and improve heat transfer. Longitudinally finned tubes are used in low capacity boilers.