Welding is a process that involves melting and then forging metals together which is basically the most common types of welding do.
The welding process has evolved from the oldest method of heating metals in a forge and then hammering the pieces together, to the invention of the gas welding torch that melts metals faster through a more intense heat, and eventually, to more efficient melting processes that employ more focused heating methods.
Current types of welding include plasma arc, gas, laser, Mig, Tig, and stick welding.
All of these processes are efficient in joining metals together, but the last three are the most popular welding processes for building and fixing things made from metal and metal alloys.
The Most Common Types of Welding Used Today
Tig, Mig, and Stick welders are what we find in most homes, construction, and other metal processing sites.
These three popular welding types focus intense heat to the exact point where metal components are to be joined, resulting to more precise, clean weld.
Tig, Mig, and Stick welding utilize different processes that produce similarly good results.
Each process has limitations that make it excel in some welding applications and alternatively, produce poor results for other jobs.
This means that there is not one welding type that will work for all applications.
The type of welding most appropriate for a job depends on the characteristics of the materials to be welded and the welding environment.
Stick welding is a robust process that is appropriate indoors and outdoors because it is not affected by wind and rain.
It employs an electric current that flows through a gap between the welding stick and the metal being worked. The welding stick is called the arc-welding electrode, which can join most metal alloys.
Though one of the oldest welding types, it remains a popular process because it is economical and effective in creating excellent bonding even when the metals being worked are not too clean, for example, metal frames that are covered by rust, oil and dirt deposits.
Stick welding machines include the simplest model with a single setting for amperage, to a unit that runs on AC or DC current with an amperage setting and a polarity selector.
Operating the machine simply requires connecting the arc-welding electrode, choosing the settings, and then proceeding with the weld.
While the process sounds simple, it is a skill that is not easy to master because of the difficulty involved in perfecting the ability to strike and maintain an arc.
Metals weld through this process produces a considerable amount of spatter that must be cleaned to produce a smooth finish.
Stick welding is appropriate for 18-gauge and thicker materials. Common applications of Stick welding include bridge construction and pipe works, maintenance chores around the home, repair of farm implements, and outdoor welding hobbies.
The proper appellation for Mig (Metal Inert Gas) welding is GMAW (Gas Metal Arc Welding). The process employs a wire welding electrode that automatically feeds from a spool at a constant, pre-selected speed.
A welding arc is produced by the electrical current that runs between the wire and the base metal, melts the wire to produce a puddle, and then the molten puddle is used to join the pieces of metals together.
The process yields a strong, clean weld that is appropriate on both thin and thicker plate materials.
A Mig welder employs an inert gas mixture supplied from a tank that creates a protective cloud around the welding arc.
A variation of this process is the Flux Cored Arc Welding (FCAW) that does not require a shielding gas but uses instead a flux-cored wire to shield the arc.
The Mig welding process is sensitive to wind and rain and requires the correct power or voltage setting and the appropriate speed of the wire feed to produce a proper weld.
Too much voltage can burn through the metal being worked, while a low setting will not produce good penetration for creating a deep weld.
To get a good weld, the correct wire feed rate and power setting must be established through trials done on scrap metal to avoid wastage. To simplify the process, there are available models of auto-set machines that determine the wire feed rate and voltage when the wire diameter and metal thickness have been factored in.
Mig welding is appropriate for thin 26-gauge and thicker steel, aluminum, and stainless steel materials. This easy to learn process produces a clean weld with minimal spatters and is most applicable to general fabrication work.
Tig welding is employed when working with alloys of copper and nickel, stainless steel, aluminum, cobalt, titanium, and magnesium.
The process requires clean materials to get a proper weld and with the preparation time, it can be a slow process.
Tungsten Inert Gas (Tig) welding employs a non-consumable tungsten electrode, an inert shielding gas such as argon to protect the weld area from contamination, and the filler metal.
The Tig welder operates with a constant current that supplies the energy that flows across the welding arc through the plasma column.
The plasma is composed of metal vapors and the highly ionized gases used in the welding process.
Tig welding is a complex process that involves many parameters, such as polarity, amplitude, pulse, type of tungsten electrode, the choice of shielding inert gas, and many others.
Compared with Mig and Stick welding, Tig creates stronger and higher quality welds, and the welder exercises more control over the process.
Because the process is complex, it is significantly slower and more difficult to master. However, it is the most versatile welding type since it can be used to weld most metals and metal alloys.
The Tig welder has numerous components, which include the welding lead cable with an electric Tig torch, a work lead or ground cable with a clamp for holding the workpiece, and the cable that holds the inert gas supplied from a tank equipped with a regulator.
The tungsten rod is held by a copper collet, which attaches to a holder with holes for gas flow. The machine itself is equipped with foot operated controls for setting the amperage and knobs for choosing the negative electrode, balance control, and pulse mode.
Tig welding is preferred by manufacturers of aircraft parts, cars components, and engine parts. Its applications are numerous and varied, ranging from the production of simple bicycle parts and exhaust pipes to the more precise work of joining tubing and piping for power plants, and the fabrication of aircraft engine parts.