What is Electric ARC Welding : Working Principle & Types

The first arc welding method was developed in the 19th century, and it has become commercially significant within shipbuilding throughout II-World War. Nowadays it remains a significant process for vehicles as well as steel structure fabrication. This is one of the famous welding methods which are used for joining metals in industries. In this type of welding, the joint can be formed by melting the metal with the help of electricity. So due to this reason, it is named an electric arc. The main benefit of this welding is, a high-temperature can be easily developed for welding. The arc welding temperature range will be 6k degrees centigrade to 7k degrees centigrade. This article discusses an overview of electric arc welding.

What is Electric Arc Welding?

The definition of arc welding is a welding process that is used for welding the metals with the help of electricity to generate sufficient heat for softening the metal, as well as when the softened metal is cooled then the metals will be welded. This kind of welding uses a power supply to make an arc among a metal stick & the base material to soften the metals at the end of the contact.

These welders can utilize either DC otherwise AC, & electrodes like consumable otherwise non-consumable. Generally, the welding location can be defended with some kind of shielding gas, slag, otherwise, vapor. This welding process could be manual, fully, or semi-automated.

Circuit Diagram

In Arc welding process, heat can be generated through an electric arc struck among an electrode as well as the workpiece. The electric arc is glowing electrical discharge among two electrodes using ionized gas.
Any type of arc welding technique depends on an electric circuit that mainly includes different parts like power supply, workpiece, welding electrode & electric cables to connect the electrode as well as workpiece toward the power supply.

The electric arc winding circuit can be formed by an electric arc among the electrode as well as the workpiece. The temperature of the arc may arrive at 5500°C (10000°F), which is enough to combine the edges of the workpiece.

Once a long join is necessary then the arc can be moved through the joint line. The weld pool of the front edge dissolves the welded surface once the back edge of the pool hardens to form the joint.
Once a filler metal is necessary for enhanced bonding, the wire can be used outside of the material which is fed to the arc region, which dissolves & loads the weld pool. A filler metal’s chemical composition is related to that of the workpiece.

Molten metal within the weld pool can be active chemically & responds through the nearby atmosphere. Consequently, the weld may be infected through oxide as well as nitride inclusion to weaken its mechanical properties. So, the weld pool can be protected through Neutral shielding gases like helium, argon & shielding fluxes from contamination. Shields are supplied for the weld zone in the form of a flux coating for the electrode otherwise in other forms.

Working Principle

The working principle of arc winding is, in a welding process the heat can be generated with an electric arc strike among the workpiece as well as an electrode. This is glowing electrical discharge among two electrodes throughout ionized gas.

The arc welding equipment mainly includes an AC machine otherwise DC machine, Electrode, Holder for the electrode, Cables, Connectors for cable, Earthing clamps, Chipping hammer, Helmet, Wire brush, Hand gloves, Safety goggles, sleeves, Aprons, etc.

Types of Arc Welding

Arc welding is classified into different types which include the following.

• Plasma Arc Welding
• Metal Arc Welding
• Carbon Arc Welding
• Gas Tungsten Arc Welding
• Gas Metal Arc Welding
• Submerged Arc Welding
• SMAW – Shielded Metal Arc Welding
• FCAW (Flux Cored Arc Welding)
• ESW (Electro-Slag Welding)
• Arc Stud Welding

Plasma Arc Welding

Plasma arc welding (PAW) is similar to GTAW or gas tungsten welding. In this kind of welding process, the arc will generate among the work part as well as the tungsten electrode. The major dissimilarity between plasma arc welding and gas tungsten welding is that the electrode is located within the torch of Plasma arc welding. It can be heated the gas at the temperature of 30000oF & change it into the plasma to attack the welding region.

Metal Arc Welding

The metal arc welding (MAW) process mainly uses a metal electrode for the welding process. This metal electrode can be either consumable otherwise non-consumable based on the requirement. Most of the used consumable electrode can be covered with flux, and the main benefit of this type of welding process is that it requires low temperature compared with others.

Carbon Arc Welding

The Carbon arc welding (CAW) process mainly uses a carbon rod like an electrode for welding the metal joint. This kind of arc welding is the oldest arc welding process and requires high current, low voltage for generating the arc.  In some cases, an arc can be generated among two carbon electrodes which are named twin carbon arc welding.

Gas Tungsten Arc Welding

The gas tungsten arc welding (GTAW) is also called Tungsten inert gas welding (TIGW). In this type of welding process, a tungsten electrode that is non-consumable can be employed for welding the material. The electrode which is used in this welding can be enclosed with gases such as argon, helium, etc. These gases will guard the weld region against oxidization. This kind of welding can be used for welding thin sheets.

Gas Metal Arc Welding

Gas metal arc welding (GMAW) is also called Metal inert gas welding (MIGW). It uses a fresh metal electrode that is protected by gas like helium, argon, etc. These gases will protect the join area from oxidation and generates multiple welding material layers. In this type of arc welding process, a filler wire can be fed constantly using a non-consumable metal electrode for welding the metal.

Submerged Arc Welding

The Submerged arc welding (SAW) can be extensively utilized within an automatic welding method. In this kind of welding process, an electrode is completely submerged by the granular coating of flux, and this flux can be an electric conductor that will not oppose the electric supply. The solid coating of flux stops the melted metal from ultra-violate radiation and atmosphere.

SMAW – Shielded Metal Arc Welding

The term SMAW stands for “Shielded Metal Arc Welding” which is also called stick welding; flux shielded arc welding or manual metal arc welding (MMA/MMAW). This kind of welding is used where the arc is struck among the workpiece as well as the metal rod. So the surface of both of these can dissolve to form a weld pool.

When the flux coating melts immediately on the rod then it will form slag & gas to protect the weld pool from the surroundings. This is a flexible method and suitable for connecting the materials like ferrous & non-ferrous through a thickness material in all locations.

FCAW (Flux Cored Arc Welding)

This kind of welding is an alternative to shield metal arc welding. This flux-cored arc welding works with an electrode as well as a stable voltage power supply so that it provides a stable arc length. This method works by using a shielding gas or the gas which is formed through the flux to give safety from contagion.

ESW (Electro-Slag Welding)

In this kind of welding, the heat is produced through current and passes among the filler metal as well as the workpiece using a molten slag to the surface of the weld. Here, welding flux is used to fill the gap between the two workpieces. This kind of welding can be started through an arc among the electrode as well as the workpiece.

The arc generates the heat to melt the fluxing powder & makes molten slag. Here the slag includes less electric conductivity that can be maintained within liquid condition because of the heat generated through the electric current. The slag gets a 3500°F of temperature and it is adequate for melting the edges of the workpiece and consumable electrode. Metal droplets will drop toward the weld pool & connects the workpieces. This kind of welding is mainly applicable to steel.

Arc Stud Welding

This type of welding is extremely reliable and used in a wide range of applications. This method is used to weld any size of metal with a workpiece through the highest weld penetration.

This type of welding can create tough, welds on a single side over base metals with 0.048-inch thickness. This arc can be formed by using a DC power supply; metal fasteners; ferrules & a stud welding gun. In this welding, there are three common methods used like drawn arc, short arc stud & gas arc stud welding.

The drawn arc method works with flux by fixed within the stud to clean the surface of metal throughout the welding. Throughout arcing, the flux can be vaporized & responds through the polluting elements within the environment to maintain the weld region clean.

The short arc method is similar to drawn arc, apart from that it utilizes no flux load otherwise ferrule. So, this method gives the shortest welding times of the arc stud welding techniques. The gas arc stud method works through static shielding gas with no ferrule or flux which makes it easier to automate.

Other Types of Arc Welding

We know that most of the industries use metal design and the most commonly used weldings are discussed above. But, several other methods can also weld two or above metals together like the following.

Electronic Beam Welding

The EBM or Electronic beam welding is used to join metals wherever electron waves get fired up at high velocity for welding one metal surface to another. Once the electron wave strikes its objective, then the affected spot will melt just sufficient to combine the adjoining part into place.

This kind of welding is very popular in the industrial area. The technique is particularly useful for the manufacturers of aerospace & automotive, who use this welding to combine several metal parts within trucks, cars, planes & spacecraft. Because of the nature of electronic beam welding based on vacuum, the method is secure for crisis work in vacated houses and buildings.

Atomic Hydrogen Welding

The AHW or Atomic hydrogen welding is an old technique for connecting metals that has frequently fallen through the edge for more efficient techniques like gas metal arc welding. One region where automatic hydrogen welding is still familiar is in tungsten welding. Because tungsten is extremely responsive to heat, this welding is secure for this method.

Electroslag Welding

This is fast welding, invented during the 1950s. This kind of welding connects heavy metals to use in equipment and machines in industries. As the name suggests, it is taken from the copper water holders enclosed in the tool which is used for electroslag welding. The water discontinues liquid slag from seeping into other regions throughout a welding session.

Carbon Arc Welding

The CAW or Carbon arc welding is a bonding technique, used to connect metals by applying above 300 degrees Celsius temperatures. In this type of welding, an arc can form among the electrodes as well as the surfaces of metal. This technique was popular once, but now it was outdated by twin-carbon-arc welding.

Oxy-Fuel Welding

This kind of welding is a method that uses oxygen & liquid fuel to fuse metal into form. French engineers Charles Picard & Edmond Fouché was invented in the 20th century. In this process, the oxygen-generated temperature is used in metal surface areas. This welding takes place in an indoor atmosphere.

Resistance Spot Welding

Resistance spot welding is used where heat connects the surfaces of metal. The heat can be generated from the resistance of electrical currents. This kind of welding belongs to a collection of welding techniques called electric resistance welding.

Resistance Seam Welding

Resistance seam welding is a technique that produces heat among the metal faying surfaces through related properties. This kind of welding begins on one face of a joint & works its mode to the other end. So, this method mainly depends on twin electrodes which are normally made of copper material.

Projection Welding

Projection welding is a method that restricts heat in a precise region for placing. This method is very common in projects that use studs, nuts & other threaded metal fasteners, wires & crossed bars.

Cold Welding

An alternate name of this welding is contact welding. This type of welding is used to connect the surfaces of metals without melting through heat.

Advantages of Arc Welding

The advantages of Arc welding mainly include the following.

• Arc welding has high speed as well as welding efficiency
• It includes a simple welding apparatus.
• It is simply moveable.
• Arc welding forms the physically powerful bond between the welded metals.
• It provides reliable welding quality
• Arc welding offers a superior welding atmosphere.
• The power source of this welding is not costly.
• This welding is a quick and consistent process.
• The welder can utilize ordinary domestic current.

Disadvantages of Arc Welding

The disadvantages of Arc welding include the following.

• A high expert operator is necessary to perform arc welding.
• The rate of deposition can be incomplete as the electrode covering tends to burn and decrease
• The length of the electrode is 35mm and needs electrode changing for the entire production rate.
• These are not clean for reactive metals such as titanium & aluminum

Applications

The applications of Arc Welding include the following.

• Used in the weldings of sheet metals
• For welding thin, ferrous & non-ferrous metals
• Used to design pressure & pressure vessels
• The developments of piping in industries
• Used in the domains of automotive and home furnishing
• Industries of Shipbuilding
• Used in the manufacturer of aircraft & aerospace
• Auto body restorations
• Railroads
• Industries like construction, automotive, mechanical, etc
• Gas Tungsten Arc Welding is used in aerospace industries to connect many areas like sheet metals
• These weldings are used for repairing dies, tools, and mostly on metals that are made with magnesium & aluminum.
• Most of the fabrication industries use GTAW to weld thin workpieces, particularly nonferrous metals.
• GTAW weldings are used where extreme resistance to corrosion as well as cracking over a long period of qualities are required.
• It is used in space vehicles manufacturing
• Used to weld small-diameter parts, thin wall tubing, making it applicable in bicycle industries

Thus this is all about electric arc welding, and it is the flexible welding method. The electric arc welding applications involve in manufacturing industries for generating powerful joints worldwide because of their features like ease & superior welding efficiency. It is most broadly used in different industries for the protection otherwise renovate works such as automotive, construction, shipbuilding, and aerospace. Here is a question for you, what is the range of arc welding temperature?