The pressure device of the seam welder adopts a cylinder, which can evenly adjust the welding pressure and will not change the welding pressure due to the fluctuation of the pressure of the compressed air source and the wear of the welding wheel, thus simplifying the cumbersome mechanical structure. Adopting anti-parallel SCR, it has high power and high stability. The welding speed of the welding machine is adjusted by frequency conversion, and the transmission part adopts ball screw, which has the advantages of speed feedback, stepless speed adjustment, high welding accuracy and simple operation.
Equipped with an integrated digital circuit controller, the heat is regulated by changing the secondary voltage of the welding transformer and the magnitude of the current per half cycle in the controller, and the continuous stopping time of the current can be adjusted within 1-99 cycle waves to a level of weekly waves to integrate the provisions of different welding specifications.
The electrode used for seam welding is a circular roller, usually 50 to 60 mm in diameter, usually 180 to 250 mm in diameter. The thickness of the roller is 10 to 20 mm and the contact surface is available as a cylindrical surface or a circular surface, in some cases a conical surface is chosen. Cylindrical rollers are widely used for welding of various steels and high temperature alloys. Due to the too uniform heat dissipation pressure, circular rollers are usually used for welding of light alloys.
Rollers are usually cooled externally. When welding non-ferrous metals and stainless steel, clean, everyday tap water can be used. When welding the usual steel, an aqueous solution containing 5% borax is often used for cooling to avoid rusting. Rollers are sometimes cooled using internally circulating water, especially for welding aluminum alloys, but their construction is much more complex.