What Is Arc Welding?
Arc welding is the process of joining metal pieces together with high heat from an arc that is generated and sustained by an electric current. There are many types of arc welding, and popular types include stick welding, metal inert gas welding (MIG), tungsten inert gas welding (TIG), and flux-cored welding.
How Does Arc Welding Work?
Arc welding uses an electric arc to generate heat and join together two metals. The power supplied to the electric arc can be alternating current (AC) or direct current (DC). DC arc welders offer a smoother arc that works better on thin materials but are more expensive than AC arc welders.
All arc welding uses an electric arc to weld and uses the following materials:
- An electrode
- An electrode cable
- A work cable and clamp
- Power supply
- Metals to join
- An arc
Arc welding uses two types of metal:
- Parent material: These are the metal parts that are joined together during the welding process
- Consumable material: These are the additional materials that are heated up in the arc and deposited over the joints to create a stronger bond
In a basic arc welding process, the power supply is switched on, and the electrode is brought near the base material. Then, intense heat is generated to produce the electric arc. This heat melts the base metal, electrode core, and flux coating. The flux coating provides a shielding environment to weld.
The molten metal is deposited between the two metalwork pieces to join them together. Once it solidifies, it forms a strong bond between the two materials. The metal workpieces are then left to cool down.
What Is Arc Welding Used For?
The most common and simplest form of welding is arc welding, so it is used across all industry sectors, including the automotive, aerospace, oil and gas, manufacturing, power, and construction sectors.
Arc welding can be used to build vessels, pressurized vessels, pipes, tanks, ships, bridges, railroads, automobiles, farm equipment, metal art sculptures, trailers, and more.
Master the Art of Welding
Types of Arc Welding
The different types can be divided into two categories: consumable and non-consumable electrode methods. Consumable electrodes undergo significant changes to their structure during the welding process. Non-consumable electrodes are not consumed during the welding process.
Consumable Electrode Methods
1. Gas Metal Arc Welding
The two types of gas metal arc welding (GMAW) are metal inert gas welding (MIG) and metal active gas welding (MAG). GMAW uses a shielding gas to protect the base metals from contamination.
The shielding gas typically comes in the form of carbon dioxide, oxygen, argon, or helium.
2. Shielded Metal Arc Welding (SMAW)
Shielded metal arc welding is also known as manual metal arc welding (MMA or MMAW), flux-shielded arc welding, or stick welding. During this process, the arc is struck between the electrode flux-coated metal rod and the workpiece, and both the rod and workpiece surface melt to form a weld pool. Simultaneous melting of the flux coating on the rod will form gas and slag, which protect the weld pool from the surrounding atmosphere. This is a versatile process that is ideal for joining ferrous and non-ferrous materials with a range of material thicknesses in all positions.
3. Flux Cored Arc Welding
Created as an alternative to SMAW, flux-cored arc welding uses a continuously fed consumable flux-cored electrode and a constant voltage power supply. This provides a constant arc length. This welding process uses either a shielding gas or just the gas created by the flux to provide protection from contamination.
4. Submerged Arc Welding
Submerged arc welding is a frequently used process with a continuously fed consumable electrode and a blanket of fusible flux that biomes conductive when molten. This provides a current path between the part and the electrode. The flux also helps prevent splatter and sparks while suppressing fumes and ultraviolet radiation.
Non-Consumable Electrode Methods
1. Gas Tungsten Arc Welding
Also known as tungsten inert gas welding (TIG), gas tungsten arc welding (GTAW) uses a non-consumable tungsten electrode to create the arc and an inert shielding gas to protect the weld and molten pool against atmospheric contamination.
2. Plasma Arc Welding
Similar to GTAW, plasma arc welding (PAW) uses an electric arc between a non-consumable electrode and an anode, which are placed within the body of the torch. The electric arc is used to ionize the gas in the torch and create the plasma, which is then pushed through a fine bore hole in the anode to reach the base plate. During this process, the plasma is separated from the shielding gas.
3. Carbon Arc Welding
During carbon arc welding (CAW), the oldest welding process, an electric arc is formed between a non-consumable carbon electrode and the workpiece, joining the metals and creating a solid bond. The use of this welding process has decreased because of the enhanced safety and convenience of modern welding techniques.
Become a Certified Welder in Erie, PA
If you’re interested in putting these different welding methods into action, you should consider taking a welding training program at a technical school in Erie.
Erie Institute of Technology offers a Welding Technology Program to prepare you for a career in the welding field. During this 12-month program, you’ll become experienced in gas metal arc welding, gas tungsten arc welding, pipe welding, and more.
Upon completion of the program, you’ll understand the common welding processes and applications at the foundation, intermediate, and advanced levels and be qualified for entry-level positions such as Welder, Welding Specialist, Welding Technologist, and Welding Engineer.
Apply online today or visit our website to learn more about our other skilled trades programs.
FAQ
What Are the 4 Processes of Arc Welding?
The four main types of arc welding are gas metal arc welding (GMAW), gas tungsten arc welding (GTAW), shielded metal arc welding (SMAW), and flux-coated arc welding (FCAW).
What Does SMAW Stand For?
SMAW stands for shielded metal arc welding, also known as stick welding.
Why Is Arc Welding Used?
Arc welding is used to join together materials that need a strong bond, especially for precision work.
Is Arc Welding the Same As Stick Welding?
Arc welding is a broad category of welding using an electric arc, while stick welding is a specific type of arc welding. Stick welding is also known as shielded metal arc welding (SMAW), manual metal arc welding (MMA or MMAW), and flux shielded arc welding.
Is An Arc Weld Stronger Than a MIG Weld?
For heavy-duty construction projects or repairs requiring high levels of bond strength, arc welding is preferred.
Manual metal arc welding uses a consumable metal electrode that has strong adhesion properties, and it requires more skill than other forms of welding because the electrode must be constantly manipulated to maintain even heat distribution throughout the welded joint.
During the metal inert gas welding process (MIG), a spool gun feeds wire into the weld puddle while an electric current maintains an even temperature throughout the joint. This prevents excess heat from being applied to one area and causing warping or distortion. It requires less skill than manual metal arc welding because there is no need to manually manipulate an electrode during the process.
MIG is better suited to projects where you need neat-looking results without too much post-weld cleanup.
Is Stick Welding the Strongest Weld?
Some argue that stick welding is the strongest weld because it penetrates thicker materials well. But TIG is widely considered the strongest weld because of the extreme heat it generates and its slow cooling rate, which results in high strength and ductility. MIG welding is a close second and is better suited for joining thinner materials with a good finish and less risk of burn-through.
Author Bio
Ross Aresco
CFO
Ross Aresco is the CFO of Erie Institute of Technology. Erie Institute of Technology (EIT) is an Erie Pennsylvania technical/trade school providing training programs for medical, computer, electronics, manufacturing, and technology careers. EIT offers programs in many different areas to suit your interests and talents.