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