Arc Welding

ARC WELDING

Arc welding is a process that uses an electric arc to join the metals being welded. A distinct advantage of arc welding over gas welding is the concentration of heat. In gas welding the flame spreads over a large area, sometimes causing heat distortion. The concentration of heat, characteristic of arc welding, is an advantage because less heat spread reduces buckling and warping. This heat concentration also increases the depth of penetration and speeds up the welding operation; therefore, you will find that arc welding is often more practical and economical than gas welding. All arc-welding processes have three things in common: a heat source, filler metal, and shielding. The source of heat in arc welding is produced by the arcing of an electrical current between two contacts. The powersource is called a welding machine or simply, a welder. This should not be confined with the same term that is also used to describe the person who is performing the welding operation. The welder (welding machine) is either electric- or motor-powered, there are two main types of arc-welding processes with which you should become familiar. They are shielded metal arc welding and gas shielded arc welding.