Essential Factors in Gas Shielded Metal Arc Welding

Nowadays, gas shielded metal arc welding (GSMAW) is widely used in various constructions such as steel structures, bridges, autos, motorcycles, construction machinery, ships, offshore structures, pressure vessels, and pipelines due to high welding efficiency.

This welding process, however, requires specific welding knowledge and techniques to accomplish sound weldments. The quality of weldments made by GSMAW is markedly affected by the welding parameters set by a welder or a welding operator.

In addition, how to handle the welding equipment is the key to obtain quality welds. The use of a wrong welding parameter or mishandling the welding equipment will result in unacceptable weldments that contain welding defects.

The Essential Factors in Gas Shielded Metal Arc Welding states specific technologies needed to accomplish GSMAW successfully, focusing on the welding procedures in which solid wires and flux-cored wires are used with shielding gases of CO2 and 75-80%Ar/bal.CO2 mixtures (GSMAW with Ar-CO2 mixed gases is often referred to as MAG welding to distinguish it from CO2 welding). In accordance with the AWS standard, GSMAW with solid wires is designated as gas metal arc welding (GMAW), whereas GSMAW with flux-cored wires, as flux cored arc welding (FCAW). GSMAW processes are popularly used for welding various kinds of metals such as mild steel, high strength steel, low temperature steel, heat-resistant low-alloy steel, and stainless steel; however, this textbook has been edited with focus on mild steel, high strength steel, and low-temperature steel, in which as many figures and photographs are employed as possible in order to help the beginners fully understand the specific technologies for GSMAW.

The information contained in this textbook includes those from the references listed below.