... sheet ,thickness 0.53-2.5m 2,Seam width no more than 3mm 3,Welding speed no less than 1000mm/min 1 ... sheet ,thickness 0.53-2.5m 2,Seam width no more than 3mm 3,Welding speed no less than 1000mm/min 4 ... WATER HEATER ACCORDING TO CUSTOMER’S REQUIREMENT AND NEED. straight seam welding machine for inner and outer tanks of solar Water heater