What is GMAW?
• Pros and Cons of GMAW • Metals Welded with GMAW • GMAW Equipment • GMAW Gun • GMAW Electrodes • Shielding Gas Characteristics • Types of Shielding Gas • Amperage • Voltage • GMAW Joint Preparation • Starting the Arc • Short Circuit Transfer Method • Globular Transfer Method • Spray Transfer Method • Pulse Arc Transfer Method • GMAW Electrode Orientation • GMAW Travel Speed • Running a GMAW Bead • Summary
Gas metal arc welding (GMAW) is an automatic or semi-automatic welding process. Shielding gas and a continuous, consumable wire electrode are fed through a welding gun. GMAW uses a constant power source such as voltage or a direct current to weld together materials such as steel and aluminum. GMAW is popular in industries such as car manufacturing due to its speed and versatility. GMAW was first developed at the turn of the 19th century, when carbon were used. By the late 19th century, metal electrodes had been invented, and by 1920, General Electric invented the early predecessor of GMAW. By 1953, the use of carbon dioxide to weld was developed. It quickly gained popularity, as it made welding more economical. GMAW is widely used by the sheet metal industry. Arc spot welding has replaced resistance or rivet welding. It is also used in robot welding, in which robots operate the welding gun and the sheet metal in order to save on time and cost. GMAW is not generally suitable for outdoor
