What Is Arc Welding: Advantages And Disadvantages?

Arc welding is a common type of welding that involves using an electric arc in order to join two or more pieces of metal together. It finds widespread application across various industries, including automotive, construction, and manufacturing. Welding by the arc is a technique that is well-known for its adaptability as well as its efficiency in forming bonds between metal components that are powerful and long-lasting.

In this blog, we will discuss how arc welding works and the benefits and drawbacks associated with using this method.

What Is Arc Welding?

In arc welding, electricity is used to create enough heat to melt the metals being joined, and the resulting junction hardens once the metals have cooled. Using a welding power supply to generate an arc between a metal rod (called an "electrode") and the base material, the metals are melted at the point of contact. Welding arcs can be operated with disposable or permanent electrodes and direct or alternating current.

Welding areas are typically shielded from flying sparks, spatter, and other debris by gas, vapour, or slag. Manual, semi-automatic, and fully-automatic arc welding methods all exist. Arc welding, which had its origins in the late 19th century, became widely used in the shipbuilding industry during World War II. Even now, it plays a crucial role in the production of steel buildings and vehicles.

What Is The Process Of Arc Welding?

Arc welding is a technique whereby the material being worked on is melted by means of an electric arc. The process begins with securing a ground wire to the substrate. The welder then touches the electrode's lead to the metal being worked on.

The welder creates an arc, or continuous plasma discharge, by electrically breaking down gas as the electrode is pulled away from the material. Direct current (DC) or alternating (AC) arc welders produce pinpoint welds in specific locations.

Metals can be fused using the arc welding technique. The electric arc created by an AC or DC power source can reach roughly 6500 degrees Fahrenheit, enough to melt the metal at the joint between two workpieces.

The electrode can either carry the current or conduct the current and simultaneously melt into the weld pool, feeding filler material to the joint as the arc is guided along the joining line by hand or machine.

When the arc heats metals to excessive temperatures, they chemically react with the oxygen and nitrogen in the air. To prevent this, a protective gas or slag is used to limit the amount of time the molten metal spends in contact with the air. Once the molten metals have cooled, a metallurgical bond is formed.

Advantages Of Arc Welding

Many different types of welding use arc welding because of its many benefits.

Versatility In Applications

Arc welding's adaptability makes it useful in many different contexts. Arc welding is adaptable for a wide range of welding applications because it can join metals of varying thicknesses.

High Productivity

As arc welding can produce high-quality welds rapidly, it can boost production significantly. Welding speeds have increased, and output has improved as a result of technological developments in arc welding machines. For this reason, it is highly recommended for time-sensitive projects.

Metal Compatibility Is Broad

Carbon steel, stainless steel, aluminium, and other metals can be welded using an arc welder. Because of its adaptability, arc welding is frequently used for a wide variety of projects.

Various Positions For Welding

Positions for arc welding range from flat to horizontal to vertical to overhead. This versatility allows for greater design freedom in welding projects involving complex geometries and contrasting metals.

Wide Range Of Arc Welding Processes

There are various arc welding techniques, each with its benefits. Flux-Cored Arc Welding, Gas Metal Arc Welding, Shielded Metal Arc Welding and are all types of arc welding that see regular use (FCAW). Because of this variety, welders can select the procedure that best meets their needs.

Cost-Effective

Arc welding is one of the most economical techniques available. Arc welding is popular among DIYers and small businesses because the necessary equipment is cheap and easy to come by. Arc welding is cost-effective because it requires minimal setup and requires inexpensive consumables like electrodes.

Appropriate For Outdoor Welding

Arc welding is preferred on construction sites and in the field because it can be done in a variety of weather conditions. Arc welding's electric arc is immune to weather effects, so that it can produce strong welds even in harsh conditions.

Strong And Long-Lasting Welds

Arc welding creates welds that are strong and long-lasting, guaranteeing the quality and durability of the joined metal pieces. The electric arc's fusion creates welds with exceptional mechanical properties, making this welding method ideal for uses where structural integrity is of the utmost importance.

Disadvantages Of Arc Welding

While arc welding has many benefits, there are also drawbacks.

Limited Applications

Arc welding's primary drawback is the narrow scope of its potential uses. Since plastics and other non-conductive materials do not conduct electricity, they cannot be welded using an arc welder. Arc welding is also not ideal for welding thin metals because the intense heat from the arc can easily warp the material.

Welding Spatter And Fumes

Welding fumes and spatter are produced when the electrode melts during arc welding. In light of the potential danger these waste products pose, inadequate precautions should be taken. Welding fumes and spatter can cause serious health problems, so it's important to protect yourself with proper ventilation and PPE.

Time Consuming

It takes a lot of time to complete an arc weld because of the extra care that must be taken with each joint. When time is of the essence, having to devote several hours to the welding process alone can be very frustrating.

Specialised Training Is Required.

The need for specialised training is another drawback of arc welding. Becoming proficient at arc welding requires many hours of training and experience. To perform welding safely and effectively, welders need a solid grasp of the underlying science.

High-quality welds produced by arc welding require training and experience. The welder must be well-versed in all relevant welding theories and safety procedures. Weak welds can compromise the structural integrity of the welded parts if the welding process is followed properly or if the welder needs to gain the necessary skill.

Surface Cleaning And Preparation

Successful welds from arc welding necessitate thoroughly cleaning and prepping the welding surface. Rust, dirt, oil, and other contaminants can lower the quality of the weld, so it's important to make sure the metal surfaces are clean before welding. Weld defects and weakened weld strength can occur if the surfaces are improperly cleaned and prepared.

Can Be Dangerous

If you use the right safety equipment, arc welding can be safe, too. Burns are possible due to the arc's high temperatures, and eyes are vulnerable to UV radiation. Arc welding produces toxic fumes, and breathing them in can be dangerous.

Different Types Of Arc Welding Process

Arc welding comes in a variety of forms. Arc welding techniques vary greatly depending on the metal being welded. Here's a rundown of the various arc welding methods.

Gas Metal Arc Welding (MIG Welding) 

In gas metal arc welding (GMAW), also known as MIG welding, the electrode is a wire fed continuously through the welding gun. A shielding gas, usually composed of a combination of argon and carbon dioxide, acts as a guardian for the molten weld pool, shielding it from the presence of atmospheric oxygen and nitrogen. 

This protective gas cloak ensures the weld's integrity and quality, like a watchful guardian defending its precious treasure from harm. The wire is slammed against the workpiece and withdrawn to create an arc in MIG welding. Gradually feeding the wire out of the welding gun as the arc is established effectively bonds the neighbouring materials.

The advantages of MIG welding include its quick welding speed, high-quality welds, and the ease with which the welding process can be controlled. On-demand welding is more challenging due to the bulkiness of welding equipment, such as gas canisters and welding equipment. 

Another drawback of MIG welding is that it can only be done in limited settings and can easily burn through materials of 1/16" or less in thickness. Because of its fast cycle times and high weld quality, MIG welding is a popular choice in the aerospace industry.

Submerged Arc Welding

Submerged arc welding (SAW) is unique among the several methods of arc welding because it keeps the arc submerged under a covering of flux particles. SAW involves constantly covering the electric arc formed between the electrode and the workpiece with solid flux material.

Once the weld pool is created, the flux undergoes melting and partial vaporisation, forming a protective liquid slag covering the weld. A shielding gas is also generated, preventing the workpiece material from reacting with atmospheric gases like oxygen and nitrogen.

The blanket of flux prevents spatter and sparks, which is great for keeping things tidy in the workplace. The flux blanket also mitigates the effects of toxic air and UV rays. The SAW process has some drawbacks, including its inability to be used in vertical or overhead orientations, its inability to be used on materials other than ferrous ones, and the need to remove slag between passes. Pipelines and other pressure vessels often employ SAW to create butt welds.

Flux-Cored Arc Welding (“FCAW”)

When compared to MIG welding, flux-cored arc welding is very similar. The machine automatically feeds a wire to the gun, which serves as the electrode. The welding process consumes the wire, but this also makes it suitable for use as filler.

When compared to solid MIG wire, this electrode's core is hollow and loaded with flux and other chemicals. When heated, the flux produces shielding gas and slag, protecting the weld from contamination, in contrast to MIG welders requiring bottled gas.

Plasma Arc Welding 

To perform plasma arc welding (PAW), a consumable tungsten electrode is housed inside the torch (welding gun) body. To create plasma, an electric arc ionises a gas (not the shielding gas) and causes it to escape from the torch. The location of the electrode within the weld gun, along with the shape of the nozzle through which the plasma is expelled, separates the plasma from the surrounding shielding gas.

PAW's benefits include a high rate of production and the potential for automation thanks to its ability to create deep, precise welds. PAW also allows the workpiece to be approached from any direction, an added bonus. The equipment used for PAW can be quite pricey, and it also produces ultraviolet (UV) radiation and necessitates water-cooling for some of its components. PAW's precision and speed make it useful in various fields, including electronics and medicine.

Gas Tungsten Arc Welding (TIG Welding)

The welding process known as gas tungsten arc welding (GTAW) uses a consumable tungsten electrode to join metals in an arc. During welding, a shielding gas (usually argon or nitrogen) is released while a torch is encased in a shroud to prevent the gas from escaping and damaging the weld.

TIG welding provides greater operator control over the welding process, produces the strongest bond possible with an arc welder, and results in a weld that is free of contaminants. TIG welding's drawbacks include its slower speeds, higher operator skill levels, and inability to be automated. TIG welding is frequently used when joint strength and flexibility are equally important.

Electro-Slag Welding (“ESW”)

When joining two pieces at least 1" thick, ESW can only be used in vertical joints. Flux fills the space between the pieces, and a wire electrode fed automatically into the gap is then embedded in the flux.

The arc is produced when a current flows. However, once the flux melts, the weld's heat, around 3,500°F, is generated by the electrical resistance of the molten flux.

This application is limited to vertical joints because flux must be used to fill the joint and then be held in place while welding. Additionally, a backer or starting plate must be installed at the base of the joint to retain the flux prior to arc lighting.

Shielded Metal Arc Welding (SMAW Or Stick Welding)

Stick welding, also known as shielded metal arc welding (SMAW), is an arc welding technique that involves melting together a flux-coated consumable electrode rod and the surface of the workpiece to create a weld joint. The arc is created in stick welding by bringing the rod close to the workpiece.

The welder then carefully moves the electrode rod clamped to the workpiece to create the arc and complete the weld. The flux-coated rod is used and eventually replaced as the weld is made.

Stick welding is advantageous because it may be performed in various settings, such as outside on windy days, with no investment in specialised equipment. Stick welding, however, is not recommended for thin materials because the electrodes wear out quickly. Stick welding is widely used in many fields, from construction to mining, heavy machinery, oil and gas industries, and beyond.

Arc Stud Welding (“SW”)

This specialised method is made for welding in anchors (or "studs"). A unique fastener that doubles as an electrode is used.

Using a specialised gun designed to produce an arch at the stud's point of attachment, the stud is pressed downward into the melting pool. It produces a bolt that is securely welded to the metal below it.

Concentrating the heat and corralling the molten metal, a special ferrule is placed around the weld, with or without shielding gas. Once the weld is complete, the ferrule is taken off and thrown away.

Conclusion

Arc welding is a common practice in many fields, including building, manufacturing, and the automobile industry. Welding is the process of joining metal parts using an electric arc to create strong, long-lasting connections. Welders attach a ground wire to the substrate and then touch the electrode's lead to the metal they're joining. The arc can reach temperatures of around 6500 degrees Fahrenheit, which is hot enough to melt the metal at the seam between two pieces of work.

Whether working with carbon steel, stainless steel, or aluminium, arc welding can adapt to your needs. Welds made using this method are durable, long-lasting, and exceptionally strong, all at a reasonable price. Limited uses, welding gases and emissions, time waste, and specialised training are only some of the disadvantages.

Thin metals are particularly susceptible to warping from arc welding because of the high temperatures involved. The hazards of welding gases and spatter necessitate the use of protective gear and adequate ventilation.

Rust, dirt, oil, and other impurities can degrade the quality of an arc weld, thus, careful surface cleaning and preparation is necessary before starting. Since burns, ultraviolet light, and toxic gases are all potential hazards, it's important to have the right protective gear on hand.

In conclusion, arc welding is a flexible and effective welding method with many benefits and drawbacks. However, it is crucial to utilise the correct safety equipment and adhere to suitable protocols to guarantee the safety of the welded components. The molten weld pool in gas metal arc welding (GMAW), commonly known as MIG welding, is protected from ambient oxygen and nitrogen by a shielding gas that is constantly delivered through a welding gun. This method guarantees the durability and quality of the weld. However, it is more difficult and restricted to specific locations because welding equipment is so large and heavy.

Submerged arc welding (SAW) is a one-of-a-kind technique in which the arc remains submerged beneath a blanket of flux particles. This method generates a shielding liquid slag that protects against spatter and sparks and lessens the impact of harmful gases and sunlight. However, it has downsides, such as the requirement to remove slag between passes, the impossibility of using it in vertical or above orientations, and the inability to use it on materials other than ferrous ones.

Similar to MIG welding, flux-cored arc welding (FCAW) employs a flux and chemical-filled hollow electrode core. As a high-speed, precise welding method, PAW permits entry from any side of the workpiece. But it can be pricey, and some parts need to be water-cooled.

To fuse metals together in an arc, gas tungsten arc welding (TIG) employs a disposable tungsten electrode. TIG welding allows for more precise manipulation by the welder, creates the strongest possible weld, and eliminates the possibility of contamination. The flux fills the space between the components, and a wire electrode is implanted in the flux, making ESW applicable only to vertical joints.

Shielded metal arc welding, also known as stick welding, is an arc welding method that involves melting a flux-coated electrode rod and the surface of the workpiece. It's useful in a number of contexts, although thin materials shouldn't use it because of electrode wear.

Using a specific fastener that also functions as an electrode, Arc Stud Welding (SW) is a specialised technique for welding in anchors.

Content Summary

• Arc welding is a common method for joining metal pieces together.
• Electric arc is used to melt the metals in arc welding.
• It is widely used in the automotive, construction, and manufacturing industries.
• Arc welding creates powerful and durable bonds between metal components.
• In this blog, we will discuss the process of arc welding and its advantages and disadvantages.
• Arc welding involves using a welding power supply and a metal rod called an "electrode."
• It can be operated with disposable or permanent electrodes and direct or alternating current.
• Welding areas are shielded from flying sparks and debris by gas, vapour, or slag.
• Manual, semi-automatic, and fully-automatic arc welding methods exist.
• Arc welding originated in the late 19th century and became crucial during World War II.
• It still plays a vital role in steel building and vehicle production.
• Arc welding works by melting the material with an electric arc.
• A ground wire is secured to the substrate, and the welder touches the electrode's lead to the metal being worked on.
• The electric arc creates a continuous plasma discharge, melting the metals at the point of contact.
• Arc welding can fuse various metals together using an AC or DC power source.
• A protective gas or slag is used to prevent chemical reactions with the air during welding.
• Arc welding is versatile and can join metals of varying thicknesses.
• Its high productivity boosts production for time-sensitive projects.
• It is compatible with carbon steel, stainless steel, aluminium, and other metals.
• Arc welding can be done in various positions, offering design flexibility for complex geometries.
• There are different arc welding processes, such as Flux-Cored Arc Welding and Gas Metal Arc Welding.
• Arc welding is cost-effective, making it popular for DIYers and small businesses.
• It is suitable for outdoor welding even in harsh weather conditions.
• Arc welding produces strong and long-lasting welds, ensuring the durability of metal pieces.
• The primary drawback of arc welding is its limited application for non-conductive materials.
• Welding fumes and spatter pose health risks and require proper precautions.
• Arc welding can be time-consuming, especially for intricate projects.
• Specialised training is necessary to perform arc welding safely and effectively.
• Surface cleaning and preparation are crucial for successful welds.
• Arc welding can be dangerous without the use of proper safety equipment.
• Different types of arc welding processes include Gas Metal Arc Welding and Submerged Arc Welding.
• Flux-Cored Arc Welding utilises a wire electrode with a hollow core filled with flux.
• Plasma Arc Welding creates deep and precise welds with the potential for automation.
• Gas Tungsten Arc Welding provides greater control over the welding process.
• Electro-Slag Welding is limited to vertical joints in thick materials.
• Shielded Metal Arc Welding involves melting a flux-coated electrode and the workpiece surface.
• Arc Stud Welding is specialised for welding anchors or studs securely.
• Arc welding is adaptable for various welding applications.
• High welding speeds and improved output are benefits of arc welding.
• It can join carbon steel, stainless steel, and aluminium, among other metals.
• Arc welding offers versatility for welding in different positions.
• There are various arc welding processes with unique advantages and drawbacks.
• Flux-Cored Arc Welding uses a hollow core electrode with flux for shielding.
• Plasma Arc Welding allows precision and speed in welding.
• Gas Tungsten Arc Welding produces strong and contaminant-free welds.
• Electro-Slag Welding is limited to vertical joints and thick materials.
• Shielded Metal Arc Welding is a versatile method used in various industries.
• Arc Stud Welding is specialised for welding anchors or studs securely.
• Proper safety measures are crucial to avoid risks associated with arc welding.
• Arc welding plays a crucial role in different industries due to its adaptability and efficiency.