Seam Welding Electrodes is a circular wheel, wheel diameter 50-600 mm and a common diameter of 180-250 mm. Wheel thickness of 10-20 mm, the contact surface shape of a cylindrical surface and two circular surface, conical surface in the individual case. Cylindrical surface rollers are widely used for welding of steel and high temperature alloy wheel of the circular surface is easy to heat indentation excessive uniform, commonly used in light alloy welding.
 The roll plate commonly used external cooling. Welding the general steel welding non-ferrous metals and stainless steel, with clean tap water can, to prevent rust, commonly used in aqueous solution containing 5% borax cooling. The roll plate is sometimes internal circulating water cooling, especially Aluminum Electrodewelder, but its structure is much more complex.