Modern welders are a demanding group in today's culture. Various factories and work environments require the help of welders to build, repair, and fix numerous types of machinery and complete metal fabrication projects.
The welding process is not easily taught and demands a lot of knowledge and hard work to do daily.
Arc Welding is a difficult skill for many to grasp but can be incredibly useful when learned.
This article will teach you the basics of arc welding, its advantages and disadvantages, and the different types that exist.
- What is Arc Welding?
- Other Types of Welding Processes
- 8 Arc Welding Types
- Advantages and Disadvantages of Arc Welding
What Is Arc Welding?
The general definition of welding involves fusing two separate parts through heat, pressure, or a combined effort between the two.
Arc welding follows a similar process but uses electricity to generate the heat.
An electrical arc forms between the base metal and electrode stick, or wire, through a reliable power source.
With this type of welding, the power source can come from a direct or alternating current, depending on the style you pick.
A direct current points the electricity in one direction. Magnetic fields have time for form and provide a consistent flow of electric currents.
An Alternating current can carry the electricity in multiple directions. It can carry electrical currents over long distances but doesn't have a consistent flow like a direct current.
This is all a very brief explanation of how arc welding works. We’ll get into the specifics in another post.
Other Types of Welding Processes
The welding process can differ with equipment, technique, and materials used.
Arc welding is only one of the many welding processes that exist in the industry.
Before we get into the different types of arc welding, here are some other welding processes that are most used today.
Oxyfuel Gas Welding
This type of welding relies on the combined power of oxygen and acetylene to create hot flames.
Through a hand-held torch or blowpipe, the flame can be as hot as 3,200 degrees to weld strong material like steel.
This welding is perfect for repairs like fixing broken pipes and loose fixtures. At the right temperature, it can also handle bronze and silver soldering.
This type of welding is very cost-effective since it doesn't rely on other materials to create the bond.
The metals join through applied pressure and passing currents from manufactured electrodes made from copper-based alloy. The electrode extracts heat to form a nugget at the welding point and waits for applied pressure.
Resistance welding is a common process in the automobile and aerospace industry.
This welding process is unique from the others because the temperature is always below the melting point. There is no use for molten metal, and it avoids defects like porosity or slag inclusions.
The metals join through applied pressure or pressure plus heat, without a filler metal. Diffusion, friction, and ultrasonic welding are the three variations of resistance welding that combine metal through coalescence.
You can recognize solid-state welding by the lack of nuggets and deformities to the base metal.
Welders find the application for this process in most aerospace industries and maintenance for leaking tubes.
This type of welding is precise and uses charged electrons through an electron gun. Electrical fields accelerate the speed of electrons to create kinetic heat and join the workpieces.
The entire process happens in a vacuumed space because any gas can disrupt the beam and cause the electrons to scatter.
The welding happens through an operating computer system for its pinpoint accuracy.
Laser Beam Welding
This no-contact process uses intense light to form a laser beam and melt two pieces of metal together. The welding takes a couple of milliseconds to generate enough heat for proper mixing and solidifying.
Two different forms of laser beam welding depend on the laser's intensity – Conduction uses low energy for a shallow weld, while penetration pierces through the metal to create holes.
This welding process uses a liquified slag to conduct an electrical current on the welding surface. The slag remains molten while heat generated from the current and joins the two workpieces together.
Electroslag welding shortens the time it takes to weld metal and increases productivity. This type of welding applies to work that involves steel plates and other heavy metals and machinery.
Arc Welding Types
Now that we’ve covered other welding processes, let’s get into the different types of arc welding.
Arc welding branches off into different sub-categories of the process. There are many applications, and the use depends on the job and its difficulty.
The type of metal also decides what arc welding process to use. Some pieces require more energy than others, and the outcome shapes the specific weld.
Here are the different types of arc welding.
Carbon Arc Welding
Most welders consider this process an old technique, though it is still used today by some. Low voltage electricity heats the two workpieces together with this variation of arc welding.
Technological advancements have made this process (created in 1881) ancient and mostly carried on through expert welders. Welders who use this technique equip hand pieces to handle the high temperatures from the electrodes.
In the past, this welding process was great for repairing defective welds, gouging cracks, and other damages.
Flux-Cored Arc Welding (FCAW)
Also known as dual shield welding, this process uses a continuous wire-fed electrode with constant voltage power applied to the welding point.
When welding, a shielding gas protects the weld pool from oxidation and possible slag formation. This technique was developed for welding structural steel.
You can find this process performed on construction sites as it handles welding that requires surfacing and hard facing.
Gas Metal Arc Welding (GMAW)
Also known as Metal Inert Gas (MIG) welding, this process is similar to the flux-cored arc welding process since it uses a metal wire as the filler material and the electrode.
The wire creates an electrical arc that comes into contact with the workpiece and melts both materials together.
The GMAW is a high-speed process that is easier to learn than, say, TIG welding. It is reliable for welding carbon steel, aluminum, and titanium metals.
Gas Tungsten Arc Welding (GTAW)
Also known as Tungsten Inert Gas (TIG) welding, a process that is challenging and requires years and training to master the craft.
This arc welding produces the weld with the tungsten material as an electrode. Argon and helium gasses protect the welding area from contamination and continuously conduct energy across the arc.
You’ll find many welders experienced in gas tungsten arc welding work in shipping yards, aerospace, and military.
Plasma Arc Welding
Plasma welding is similar to GTAW as it uses tungsten as an electrode. The difference between the two processes comes from a nozzle used to cover the electrode.
Ionized gasses create hot plasma blasts and weld the metals with a narrow precision. The high-speed heat concentrations make up for the low electrode consumption.
This process is good for automatic welding, and used for fillet welds and eliminating spatter.
Shielded Metal Arc Welding (SMAW)
Also known as stick welding, this process uses a flux-coated electrode with a metal rod as its core piece. The coating disintegrates during the weld and releases a vapor that offers a shielding gas and an extra slag layer.
The welding speed is slow compared to other arc welding techniques but offers customization for penetration size and the amount of spatter.
Very useful in work areas with tight spaces. This type of arc welding is often used for repairs, in construction, and welding aluminum.
Submerged Arc Welding
This type of arc welding is similar to SMAW as they both require some form of coating. In this case, the arc is covered under a layer of powdered flux.
This blanket of granular material provides electrical conduction between the joining metal and the electrode. It requires a steady hand since the welder can't see beyond the coating.
This process can only be done in flat and horizontal positions. It is often used in fabrication work using heavy steel plates.
Atomic Hydrogen Welding
This arc welding process uses two tungsten metal electrodes within a hydrogen atmosphere. The electric arc breaks up the hydrogen molecules in the process and combines them again through extreme heat.
This process produces one of the hottest flames, between 3400 and 4000°C . That heat is hot enough to melt through tungsten.
Like carbon arc welding, this is another process that many welders consider outdated.
Advantages and Disadvantages of Arc Welding
These processes have their uses and drawbacks. It requires the right amount of electricity to function properly, and, depending on the job, the correct voltage level.
Here are some pros and cons of using the arc welding process.
One of the best things about arc welding is how cost-efficient the process is, compared to other welding techniques.
In most cases, this type of welding is relatively easy to learn, with the right instruction and plenty of practice, and can apply to most types of metals.
The equipment needed for arc welding is portable and can be easily carried around the necessary spots.
The production rates outweigh the cost of units per weld and provide a strong yield.
Arc welding should only be used on sturdy materials that can handle the high intensities of heat. Soft materials and thin metals can be ruined. It’s best to work on strong metals.
As well as this, residue and waste the process leaves behind can be too toxic for exposure. What follows after arc welding is a sterilizing clean-up procedure.
While this is definitely something that can be learned at a professional level, arc welding is difficult for most people to learn on their own.