Arc welding is an electrical heat-based metal jointing process. It is commonly used in different industries including aerospace and automotive industry. So, knowing arc wedding basics is important to working on precision arc welding projects.
In this guide, we will detail the basic principle of arc welding. If you are finding a comprehensive guide about arc welding then it is right for you.
So, let’s move on-
What Is Arc Welding?
Arc welding means melting and jointing welding materials by applying an electric arc. An electric arc is created by using high heat from AC or DC power source. This electric arc melts the jointing edges of workpieces and strengthens bonding after the melted edge is solidified.
How Does Arc Welding Work?
Arc welding requires some essential things to complete a welding project. These things are
- a ground cable
- an electrode cable
- AC or DC power supply and
- an Arc
Arc welding works based on AC or DC electrical energy. The current flow through the wire to the torch and creates high heat generating the electrical arc. Due to the intensive heat, the arc heats up and melts the metal workpieces.
The welding arc needs to be heated up to about 6,500°F temperature. Remember that, arc welding produced at high temperatures can react with the air. The reaction of the molten metal with air can cause various defects on the arc welding surface. That’s why it is advised to use some protective things to prevent the air reaction such as mask or helmet.
There are two core ways to prevent air reaction while welding. The first effective way is shielding gas to protect the hot weld area from atmospheric contamination. The second way is to use flux that works as shielding gas when get in touch with the atmospheric air reaction.
Advantages and Disadvantages of Arc Welding
- This welding process is very speedy and increases the production rate in larger-scale.
- It is cost-effective because very little equipment is required in this welding.
- Arc welding accessories are portable. So, you can go anywhere for arc welding without transporting heavier equipment.
- It is Compatible with dirty metal, windy and rainy weather while welding
- It is easy to do arc welding on versatile materials, including steel, aluminum, and cast iron.
- The high electric force created by intensive heat helps for deeper penetration into workpieces and makes welding durable.
- Arc welding may result pollution with huge sparks, fumes and heat.
- The finished welding surface may get faulty with porosity and spatters because of intensive heat. Besides, the workpieces may get deformed due to intensive heat.
- It requires to use shielding gas or flux to eliminate the atmospheric gas reaction.
- Difficult to move in wide range of areas when welding on a large scale
- The electric power supply is mandatory in arc welding, which may not available in some places.
Application of Arc Welding
Arc welding is a popular welding process that is used in plethora of sectors. Let’s see some common applications of arc welding-
- Repairing: Arc welding is an effective way to repair metal components. It can perform well to make stronger joints between cracks and patches of old and distorted metals. Also, it helps to join new metal components.
- Ship Building: It is excellent for building fundamental base of the ship. One special water-tight seal is used to apply arc welding in shipbuilding.
- Piping: The uses of arc welding have increased much in various piping industries.
- Automotive: Arc welding is used for joining car parts and other vehicle parts. So, it plays a great role in the automotive industry.
Different Types of Arcs Welding
There are several types of arc welding based on their uses, effectiveness and conveniences. It can be classified into several types for example: stick welding, mig welding, plasma welding, tig welding, and more.
Among the various types, some arc welding requires consumable electrodes, and some require non-consumable electrodes. Let’s know about them-
Arc Welding With Consumable
Arc welding done with consumable electrode material is called consumable.
- Mig Welding (GMAW)
Another name for mig arc welding is Gas Metal Arc Welding. Like plasma arc welding, an electric arc is created between the electrode and workpieces in mig welding. As a result, the workpieces get melted and creates a strong joint.
Shielding gas is used in MIG welding to protect the molten welding materials from atmospheric reactions. Carbone di oxide, Argon or mix of them are used mostly in Mig.
- Flux Core Welding (FCAW)
Flux core arc welding (FCAW) requires a DC power supply to generate heat. The arc stays stuck between the continuously feeding electrode and workpieces in this process. And consequently produces high heat and melts the workpieces to make join strong.
Flux is used in stead of shielding gas to protect the arc from contamination. That is why the welding is called flux core welding. I have covered the term flux in another blog provided you don’t know what flux is.
- Stick Welding (SMAW)
Stick welding is also known as Shielded Metal Arc Welding (SMAW). It is one of the most commonly used and easily accessible arc welding method. A hand-held consumable electrode material is used in this welding process.
This hand-held electrode comes with a flux coating at the tip that can melt the metal while coming to the touch. AS a result, it produces shielding gas and slag to protect the welding surface from oxidation.
- Submerged Arc Welding (SAW)
Submerged arc welding means creating an electrical arc between workpieces and electrodes. Generally, powdered flux and alloy elements are used in this welding process. The powdered flux works as a shields gas and slag to protect the welding surface from air reactions. The core advantage of using submerged welding is preventing splashing welding materials from around the working area. Besides, it prevents the emitting of radiation.
- Electro Gas Arc Welding (EGW)
Electro-gas arc welding is mainly used to weld on vertically positioned metal. It requires consumable electrodes to create an electric arc for melting the workpieces. Moreover, electro-gas welding needs to be more stable than other welding because it is used to penetrate through thicker metals.
- Arc Stud Welding (ASW)
Arc stud is also known as drawn arc stud welding. It needs a consumable electrode to complete the welding task. This procedure helps to join fasteners with the base metals through the electric pressure.
With stud welding, it is easy to weld a large-diameter fastener on thicker and rougher metal workpieces. There are several types of applications where arc stud welding is used. The types of metal might be threaded, unthreaded and tapped.
Arc Welding With Non-consumable
Arc welding done with non-consumable electrode material is called non-consumable.
- Tig Welding (GTAW)
TIG arc welding is also known as Gas Tungsten Arc Welding. Usually, the non-consumable electrode is used in this arc welding process. The non-consumable electrode passes electric power through the arc to create the required heat. Since tungsten is an electrode, you must use filler wire and shielding gas for this method. Filler metals get melted and joins the workpieces using seamless welding.
- Plasma Arc Weld
Plasma arc welding is very similar to tungsten gas arc welding. Electric pressure stayed in the electrode and workpieces in the plasma welding process. The main difference between tungsten and plasma arc welding is using a torch. In a plasma arc, a torch holds the electrode to join metal.
We hope you got the crucial points on arc welding basics. Now, you can easily decide which arc welding process is required for which purpose. Arc welding mainly works based on an electric power supply.