The Gas Metal Arc Welding Process occurs when an arc is formed between a wire electrode and the workpiece, melting both and creating a molten pool. The wire is continuously fed, and a shielding gas is used. This process is considered semi-automatic because wire feeding and arc length are power controlled, while travel speed and positioning are manually controlled by the welder.
To be successful, the welder must learn to properly guide and clean the welding gun, and optimize voltage, flow, and wire feed speed. The welder's travel speed affects the quality and shape of the weld. The Gas Metal Arc Welder must judge the relationship between the size of the molten pool and the thickness of the joint to determine the correct travel speed.
What Gas is Used in Gas Metal Arc Welding? Gas Metal Arc Welding requires a shielding gas because it is used to protect the weld pool from contaminants in the air. The most commonly used types of gas in this process are argon and helium, which are both inert gases, meaning they will not have a chemical reaction.
Gas Metal Arc Welding Temperature: In Gas Metal Arc Welding, the base metal melts at around 3,000 degrees Fahrenheit and fuses with the filling metal.
Gas Metal Arc Welding Power Supply: Most Gas Metal Arc Welding and other semi-automatic processes use a Constant Voltage (CV) power supply. The power supply provides a constant voltage to the arc length in this process. There is a self-correction arc length function that helps to produce stable welding conditions.
Gas Metal Arc Welding Polarities: Gas Metal Arc Welding process uses reverse polarity operation, where the wire electrode is the positive pole. This generates more heat and helps to reduce the possibility of defects caused by non-fusion.
There are many advantages to using Gas Metal Arc Welding which makes it one of the most widely used welding processes:
Easy to Learn: Compared with other welding processes, Gas Metal Arc Welding process is considered a simple, single-handed operation that is easy to learn.
Wide Applications: Gas Metal Arc Welding can be used to weld various metals and alloys, and there are many types of filler wire electrode materials, achieving multiple types of welding.
Less Cleaning Work: The shielding gas in Gas Metal Arc Welding protects the arc, which means that spatter and slag production is minimal, and there is less cleaning work after the job is done.
Control: There are many settings on the Gas Metal Arc Welding machine that allow the user to control polarity, wire feed speed, and current intensity.
Efficient: Gas Metal Arc Welding is not only efficient in cleaning but also in single-handed operation, which improves control, increases welding speed and automation, making it easier for welders to work.