Submerged arc welding, gas tungsten arc welding, and gas shielded welding differ significantly in their welding methods, application areas, and characteristics.

Submerged arc welding is a method of welding that uses welding wire and flux. The flux buries the arc like sand during the welding process, primarily used for thick plate welding. It offers high production efficiency, excellent welding quality, and is easily mechanized and automated. However, submerged arc welding has certain requirements for welding position and component assembly accuracy, thus its application is somewhat limited.

Argon arc welding is a welding technique that utilizes argon gas as a shielding medium. It can be used to weld almost all metalwork, particularly high-quality materials such as stainless steel and titanium alloys. The welding process is smooth and produces minimal spatter, although it is relatively expensive. Moreover, argon arc welding poses potential hazards such as high-frequency electromagnetic fields and arc light injuries.

Gas shielded welding, including CO₂ gas shielded welding, is a welding technique that uses gases (such as carbon dioxide or argon) as a shielding medium to prevent contamination of the weld seam by oxygen and nitrogen from the air during the welding process. This method is suitable for welding high-alloy materials like stainless steel and aluminum alloys, as well as for components that require high welding quality. CO₂ gas shielded welding is less likely to produce cold cracks after welding, and it offers low cost and high efficiency. However, the electric arc and dust produced during gas shielded welding may have a significant impact on the welder's health.

In summary, each of these three welding methods has its own characteristics and applicable fields. When selecting a welding method, it is necessary to consider various factors, such as specific welding requirements, material types, and working conditions, among others.