Welding Processes 101: Arc and Gas Welding  

WeldingWelding is an industrial process wherein two or more metal pieces are fastened together with the use of extreme heat and pressure. As heat softens the metal, pressure is applied to effectively attach the separate pieces together as one.

There are different welding processes for different applications. Structural steelwork engineers and contractors can recommend the best solution, depending on the type of job. Two of the common processes used in the construction industry are arc and gas welding.

Arc Welding

Popularly used because of its low cost, arc welding involves a device that discharges electric current. The process is called arc welding due to the arc formed across the gap when the device and the electrode tip get close to the pieces to be attached. At the electrode tip, the arc produces extreme heat that is about 6,500 degrees Fahrenheit. This melts both the metal piece and the electrode, creating a pool of molten metal that experts refer to as the crater. When the welder moves the electrode along the joint, the crater hardens behind it. This results in an effective fusion bond.

Gas Welding

This form of welding involves oxygen and acetylene. Used by welders since the early 1900s, oxy-acetylene welding produces an extreme temperature that reaches over 6,000 degrees Fahrenheit. This amount of heat is useful not just for welding, but for cutting as well. Combining the gases creates a flame that melts the surfaces of the metal pieces to be joined and allows them to flow together. Welders usually add a filler alloy to avoid the incidence of oxidation, as well as to make the attachment process smoother.

Arc and gas welding processes are highly effective in joining any metal pieces together. Choosing which process to use would depend on a couple of factors, though. You need to take into account the thickness of the metal and the complexity of the job in general.