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https://weldguru.com/mig-welding-safety/

This article cover safety precautions that need to be taken when using the GMAW process.

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Affiliate Disclaimer: This post may contain links that will earn us a commission at no cost to you. This helps keep Weldguru a free resource for our readers.

MIG welding safety should be taken seriously as the welder needs to be protected against the forces of heat, gas, electricity and light that MIG welders produce.

The principles of safety are fairly straight forward and focus on:

Cleanliness and organization, locate welding machine in a dry location on floor of a welding booth

Adequate lighting

Checking for gas leaks

Ventilation per OSHA standards (also check MSDS for each metal being welded). Use a respirator when required by the MSDS.

Safe storage of flammable gases and liquids such as in a specially designed storage locker

Check integrity of electrical cords

Protect against burns caused by metal heating, electrodes and from ultraviolet light

Regular equipment maintenance and proper installation

Keep a first aid kit on hand

Use proper welding gear that includes eye protection and protective clothing (shoes/boots, gloves, long sleeve shirt, pants over tops of shoes with optional shoe covers (called spats), hat or welder beanie, leather jacket or apron.

Keep a fire extinguisher on hand

When thinking about safety also think about those around you. A welding arc should not be seen by the naked eye closer than 20 feet away.

Precautions

Ventilation, Fumes and Gases

Can harm you, keep your head out of the fumes. Use general ventilation, respiratory protective equipment or local exhaust ventilation as recommended in the MSDS for the material being welded.

Do not weld on a dirty plate or plates contaminated with unknown material. Remove all paint and galvanized coatings before welding.

Be careful when working with carbon dioxide shielding since it can be hazardous. Use appropriate ventilation.

Use a higher percentage or argon gas along with the pulse-spray transfer method to reduce gas-related hazards.

Be especially cautious when welding with the following metals since they have toxic vapors:
Keep Degreasing Away From Welding Area
Keep any degreasing away from welding area. Degreasers are made with carbon tetrachloride, perchloroethylene and trichlorethylene can break down into phosgene when exposed to arc rays.

Arc Rays and Spatter

Beware of arc rays and mig spatter when reviewing MIG welding safety plans.

Arc rays and spatter can injure eyes and burn skin. Wear eye, ear, and body protection to prevent this.

Electric arc radiation can burn eyes and skin the same way as strong sunlight. Electric arcs emit both ultraviolet and infrared rays. Use the correct filter.

Electrical Shock

ELECTRIC SHOCK can kill you. Do not touch live electrical parts. Turn off the machine when doing any repair work on the gun. Unplug the machine when doing any repair work inside the machine. Shock can occur if you touch the electrode and work or ground at the same time.

When you pull the trigger the coil can shock

Never touch the metal parts of the electrode holder and the electrode with wet clothing or skin

Keep insulation between the metal being welded or ground

Wire Feeder Safety

When adjusting or aligning drive rolls turn off the power. There are also multiple points where fingers can get pinched.

Do not point wire at the body.

Protective Equipment

The following welding protective equipment is called for when Mig welding process:

Welding mask: as a general guideline a top-rated MIG welding helmet with a lens rated number 6 is for work up to 30 amperes. Number 14 should be used when using more than 400 amperes (see table below). As a rule of thumb, close your eyes immediately after welding, if you still see the arc then you need to go to a darker lens shade.

Steel capped boots or other appropriate footwear

Eye protection and safety glasses - protects against a condition called welders flash that can permanently damage eyesight. GMAW typically uses shade numbers 11 - 12.

Long hair covered

Protect the back of the head and neck from problems caused by reflected radiation

Protective clothing or leather apron

Leather gloves

Welding sleeves or long sleeve dark color shirt: the dark color reduces reflection.

Knee pads - if you plan to be working low down for long periods

Materials that withstand radiant energy include wool, leather and aluminum-coated cloth.

As a rule of thumb, start with a shade that is too dark to see the weld zone. Then go to a lighter shade which gives a sufficient view of the weld zone without going below the minimum.

In oxy-fuel gas welding or cutting where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light of the (spectrum) operation.

Experience has shown that lighter filters may be used when the arc is hidden by the workpiece. (Information taken from ANSI Z49.1.2005.)

Safe Welding Space

Fumes and sparks are two of the hazards that need to be accounted for when designing a space to weld. Consider the following:

Lighting: to make sure that you can see your work.

Flame Retardant Room: Check the walls and floors for flame retardant qualities. Floors should be concrete and cinder blocks for the walls are the types of materials that are needed. Plan out where each piece of equipment will be stored or kept.As a rule of thumb, anything flammable should be at least 35 feet from anything being welded.

Electrical: Anticipate the types of equipment and number of machines that will be running to plan your power needs. Many types of welding equipment will run on 110 single phase service, which is the type found in U.S. homes backed up by 20 amp circuit breakers. You may also want access to 220 phase service (same as what is used for a home clothes dryer) to equipment that requires this type of service.

Ventilation: The gasses and smoke created by welding can be harmful if not properly ventilated.

MIG Welding Safety Operations

Pre-Operation

Use this as a basic Mig welding safety checklist:

Clean and organized work area

Remove flammable liquids from area

Check ventilation

Remove any jewelry and loose clothing

Inspect gas lines for leaks

Operating MIG Equipment

Clear work area from unauthorized personnel

Position the flash blind in order to protect any nearby personnel

Check cable position to avoid any damage due to sparks or materials that can fall

Check all equipment settings

Much of the risk from welding fumes and smoke can be reduced by using a shielding gas with a higher percentage of argon and pulse-spray mode of transfer

Remember that wire feeder pushes wire, no need to push gun into arc

Keep nozzles free of spatter - MIG pliers can help with this. Spatter can build up and electrically connect the insulated nozzle to contact tube. A clean nozzle will have spatter fall off on its' own. You can use an anti-spatter compound on nozzle and gun and contact tube end. Whatever you do, do not clean the nozzle by pounding it on a hard surface. It can break and become damaged.

Post Operation

Turn off machine

Firmly close gas cylinder

Return the welding gun to storage

Gas Cylinder Safety

Gas is also a concern when planning for MIG welding safety. High-pressure bottles or cylinders are used in the MIG welding process.

Bottles must ALWAYS be chained. Bottles not being used must be capped.

Most cylinders need to be periodically tested and re-certified. Every cylinder should have markings that indicate its' certification status. OSHA sets standards for acetylene, LPG, oxygen and hydrogen.

Store cylinders in a protected area away from hazards such as grease, cold and fire. They should be secured so that they will not be knocked over.

Be sure to use the correct flow-meter and regulator for the cylinder being used.

Empty cylinders are stored upright with a closed valve.

High-pressure bottles have double seated valves and should be ALL ON or ALL OFF.

Also read: Choosing The Right Size Gas Cylinder for MIG & TIG

Fire Safety

For MIG welding safety do not weld near flammable materials or fumes. For example, keep welds away from areas where materials are painted or dipped.

Also do not use flammable flooring or tables. Keep welding equipment away from flammable walls.

If welding a container. ensure that any flammable materials have been adequately removed.

For Additional Reading
OSHA Welding Standards

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Mig Welding Safety: Guide and Pictures - Weld Guru

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Affiliate Disclaimer: This post may contain links that will earn us a commission at no cost to you. This helps keep Weldguru a free resource for our readers. MIG welding safety should be taken seriously as the welder needs to be protected against the forces of heat, gas, electricity and light that MIG welders produce.

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https://weldingpros.net/mig-welding-applications/

This article provides a brief overview of some of the applications of the GMAW welding process.

There are many applications for the GMAW process as it is one of the most versatile forms of welding. This article gives a few examples of what can be done with this process.

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WeldingPros - Welding Career Guide, How To and Gear Reviews

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Arc produces heat, which leads to melting the base metal. Molten metal finally makes a perfect welding joint. The MIG gun also supplies shielding gas, protecting the welding bead from defects. Therefore, you can efficiently utilize it to join dissimilar metals, and the weld pool is not contaminated by interacting with the air in the atmosphere.

This simple explanation may serve you as a reminder, but if you want to learn about the MIG welding process in detail, feel free to check out our extensive how-to article.

MIG Welding Machines

Today, the welding market is overflowed by MIG welders due to low prices and high versatility. You can buy a cheap MIG welder for a couple of hundred bucks or opt for an industrial-grade machine suitable for heavy-duty use.

Before you make a purchase, you should make your goals straight. Hobart and YesWelder assemble one of the best for money MIG welders, and you won't have to break a bank. Handler 140 and MIG 250DS are among the best MIG welders for hobbyists.

On the other hand, Miller and Lincoln machines will do their part if you look for a real workhorse. However, you will have to be ready to pay more than quite a few bucks for Millermatic 211 or Lincoln Pro MIG. Our best MIG welder article can assist you in choosing the suitable machine for you.

Common GMAW or MIG Welding Applications

Even though MIG welding takes part in countless industries, it thrives in several branches. It is most commonly used in automotive, construction, and high production manufacturing.

Automotive Industry and MIG Welding

In addition, results are satisfying since the weld is almost invisible and long-lasting. Some companies, such as Eastwood, even design their machines for auto-body repair and maintenance.

Welders are designed to provide the right amount of heat to stop the thin metal from bending and changing properties. Therefore, you can see the relation between MIG welding and the automotive industry.

There is no doubt this bond will last, but technology advances significantly. As a result, some manufacturers today use a hybrid process called laser MIG welding. These two processes result in enhanced welding possibilities, weldability, and welding reliability for many different materials and constructions. However, the automotive industry is still unimaginable without MIG welding.

Construction and MIG Welding

In addition, the US government invests money in infrastructure repairs, meaning job opportunities will continue to rise. So if you are considering a welding career, construction might be the right choice.

Mass Production Manufacturing and Metal Inert Gas (MIG) Welding

The US Bureau of Labor Statistics shows that machine manufacturing employs the highest number of welders 5.530. Next on the list is motor vehicle parts manufacturing with 4.900.

Particular MIG welding tasks may include working with fabricated metal products, mining machinery and agricultural products, and many more.

Robotics and MIG Welding

Due to low prices and high productivity, MIG welding is often used in assembly lines. In addition, companies have found it cheaper to install robots in recent years than training and employing MIG welders.

MIG welding robots are capable of welding in all-position, adding flexibility to the welding system. Some of the advantages that companies see following MIG welding automation are: safety from dangerous fumes, higher quality welds, and more efficient processes are just

MIG welding robots are economical and easy to incorporate into an assembly line. That's the reason why they found their way into the automated automotive and manufacturing industry.

Nonetheless, they only justify the cost if the MIG welding is fully compatible with the industry goals. On the other hand, complex applications require complex solutions, and the MIG welding robots might be left out. you can read more about robotic welding in this article.

Railroad Repair

Those are some of the drawbacks which will make you think it doesn't work well in the pipeline or railroad repair.

Yes, you cannot use MIG welding to join railways, but you can use it to deal with defects that negatively impact the integrity of the rail track. Most commonly, those are wear of metal, broken plates, broken bolts, wheel burns, and rail end batter.

As a matter of fact, railroad rolling stock manufacturing holds the highest concentration of employment in welding. Welders take 2.5% of industry employment.

Pipeline MIG Welding

Despite Stick welding (Shielded Metal Arc Welding) being the most common pipeline welding process, MIG welding is often used due to higher productivity. You can work much quicker than SMAW, and GMAW beads are cleaner.

So, you can do it faster, there is less spatter, but the job is usually prefabricated in indoor conditions. Due to cleanliness, MIG welding is used to join sewage or water system pipes. That's why you can drink the water safely.

In the past, many welders were worried about the strength of the MIG welds, especially when dealing with thicker metals. Stick welds were drastically stronger back then, and you didn't have to carry bulky equipment around.

However, technical advancement increased the strength to match SMAW electrodes, so now MIG wire has a tensile strength of 55.000-70.000 PSI. Despite various technical improvements, many believe GMAW operator skills can easily impact the quality of the weld. That's why some still prefer Stick welding over inert gas MIG welding in a large-scale pipeline systems.

Final Thoughts

MIG welding is one of the most straightforward welding methods, making it perfect for beginners. However, advantages such as low prices and high productivity made it suitable for industrial service.

Today, MIG welding is an essential part of the automotive, construction, manufacturing, and some industries with mass production. The ability to weld metal of variable thickness and type (carbon steel, stainless steel, aluminum, etc.) makes it suitable for different applications.

On the other hand, MIG welding comes short when working in windy outside conditions and dealing with extra thick metals. Flux-cored arc welding takes its part there.

Some prefer TIG welding when dealing with aluminum, and MIG and tig welding are the most popular methods. However, MIG welding is easier to learn compared to Tungsten Inert Gas welding. TIG welding includes non-consumable tungsten electrodes, but you still buy filler material just like MIG wire welding.

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Arc produces heat, which leads to melting the base metal. Molten metal finally makes a perfect welding joint. The MIG gun also supplies shielding gas, protecting the welding bead from defects. Therefore, you can efficiently utilize it to join dissimilar metals, and the weld pool is not contaminated by interacting with the air in the atmosphere.

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https://weldinganswers.com/modes-of-metal-transfer-globular/

Globular GMAW is probably the least common of the three main metal transfer types and is explained here.

This article covers the Globular mode of metal transfer in depth. This mode of metal transfer is the third most common type and should be known to anyone leaning about GMAW.

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https://weldinganswers.com/modes-of-metal-transfer-spray/

Spray transfer is one of the types of GMAW that is used extensively to this day.

Spray transfer is probably the second most common form of GMAW metal transfer after short circuit. This article covers spray transfer in depth.

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https://weldinganswers.com/modes-of-metal-transfer-short-circuit/

Short circuit GMAW is one of the most popular forms of the welding process. This article covers short circuit GMAW in depth.

This source also contains links to the other modes of metal transfer associated with GMAW. The article even covers the shielding gas needed and the use of the different mixes.

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The modes of metal transfer refer to the different ways in which the filler metal (electrode) is transferred through the welding arc and into the weld puddle. We can write a book on this topic but we’ll keep it simple to provide an understanding of the different modes of transfer, what they require…

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The effect of voltage and current in the GMAW process

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The effect of voltage and current in the GMAW process

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https://ewi.org/gas-metal-arc-welding-basics-welding-current-welding-voltage/

This article provides an overview of the effects of changes in voltage and current in the GMAW process.

This article provides a good explanation of the effects of voltage and current in the GMAW process with diagrams included. More terminology is also introduced to the reader providing a deeper understanding of a tough topic.

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Gas metal arc welding (GMAW) is a welding process that has been commercially available for around 60 years. The basic operation of the GMAW process occurs when an electrical arc is established and maintained between a base material and a continuously feed wire electrode. The molten weld pool is shielding from the atmospheric conditions by an envelope of shielding gas that is flowed continuously around both the wire filler metal feeding in the weld pool and the weld pool itself.

The heat of the electrical arc serves to locally melt the base metal as well as melt the wire filler metal that is being fed into the weld. There are two entities at play in the GMAW process:

1. Burn Rate: This refers to the rate, inches/minute (in/min) or meters/minute (m/min), at which the wire filler metal is melted or consumed by the thermal energy of the welding arc. The primary variables that control the thermal energy of the arc are the welding current, welding voltage, and shielding gas composition.
2. Feed Rate: This simply refers to the rate, again in in/min or m/min, that the wire filler metal is feed into the weld.

For a stable welding arc, the burn rate and feed rate need to equal each other. For instance, if the burn rate is higher than the feed rate, the wire filler metal would melt back to the contact tip and cause issues. With the exception of short circuit metal transfer, if the feed rate is higher than the burn rate, the wire filler metal would feed into the molten weld pool, again, causing issues.

There are four main variables of the GMAW process that affect both the penetration profile into the base material and weld bead profile above the base material for a given weld:

1. Welding Current
2. Welding Voltage
3. Contact To Work Distance
4. Travel Speed

The information below observes thevery basic effects that the welding current and welding voltage variables have on the weld penetration profile in the base material and the weld bead profile that lies above the base material. The base material used in for the following welds is cold rolled 1018 bar stock and the shielding gas is 90% Argon - 10% CO2.

GMAW with Constant Voltage Power Supply
The GMAW process commonly uses a constant voltage power source (GMAW-CV) that allows for a relatively constant welding voltage output over a range of welding currents. For GMAW-CV the welder selects the wire feed speed (WFS) on the wire feeder unit and an appropriate voltage on the welding power supply. The internal circuitry of the power source then supplies an appropriate amount of welding current necessary to maintain a stable arc. The GMAW process variables of current and wire feed speeds are interrelated so one cannot be independently adjusted without affecting the other byjust altering the WFS selector setting on the power supply itself.

Welding Current
The variable of welding current primarily controls the amount of weld metal that is deposited during welding. As discussed earlier, the process variables of WFS and current are directly related so as one increase so does the other and vice versa. Welds 1-5 demonstrate this relationship, Figure 1 & 2. Holding all other variable constant, the WFS was incrementally increased from Weld 1 through Weld 5 which consequently increased the welding current. Remember, the welder sets the WFS not the current level on a GMAW-CV power supply, so the primary way of adjusting current is by adjusting the WFS. Table 1 show the welding data from these welds.

The welding current also affects the weld penetration profile. Holding all other variables constant, as the welding current increases the further the weld will penetrate into the base material. This increase in weld penetration is seen in Welds 1-5, Figure 1. The driving force behind the fingerlike penetration in Welds 3-5 is that the metal transfer mode in the welding arc was spray metal transfer mode. This metal transfer mode typically transitions from globular to spray mode transfer above approximately 190 amps of welding current for certain metal and shielding gas combinations.
Table 1: Welding Current Data

Welding Voltage
Welding voltage primarily controls the arc length which is the distance between the molten weld pool and the wire filler metal at the point of melting within the arc. As the voltage is increased, the weld bead will flatten out more and have an increasing width-to-depth ratio. Welds 7-11 in Figure 4 show this widening of the weld beads as the voltage is increased. Table 2 shows the weld data for these welds.
Table 2: Welding Voltage Data

Note that the penetration remained relatively constant for Welds 7-9. Despite the change in voltage, the welding current did not change therefore weld penetration did not appreciably change. Welds 10 & 11 both exhibited an increase in fingerlike penetration as well as in increase in welding current. As the arc length increases proportional to an increase in voltage, the electrode extension, distance from the contact tip to the point where the welding wire is melting in the arc, consequently decreases, Figure 3.

As the electrode extension decrease so also does the resistance to the welding current flowing through that portion of the wire. Using Ohm's law and holding the voltage constant, the welding current would consequently increase. The current was indeed increased and enough so to change the transfer mode from globular to spray which is evidenced by the increase in fingerlike penetration. This phenomenon will be further explained in the next blog that will look at the affect of the variables of contact to work distance (CTWD).

Next time we will look at the variables of contact to work distance (CTWD) and travel speed and observe how they affect the weld bead profile and base material penetration.

For any questions on the basic operating principles of GMAW, please contact Nick Kapustka at nkapustka@ewi.org.

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Gas Metal Arc Welding Basics: Welding Current & Welding Voltage - EWI

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Gas metal arc welding (GMAW) is a welding process that has been commercially available for around 60 years. The basic operation of the GMAW process occurs when an electrical arc is established and maintained between a base material and a continuously feed wire electrode. The molten weld pool is shielding from the atmospheric conditions by ...

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What you should know about a welding career

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What you should know about a welding career

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https://waterwelders.com/reasons-why-welding-is-a-great-career-choice/

This article provides Pros and Cons to working in the welding field.

If you are looking into types of welding, such as GMAW, you should also know what career opportunities come with the process. The article covers what I consider the major Pros and Cons in the welding field.

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10 Reasons Why Welding is a Great Career Choice - WaterWelders

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Are you thinking of becoming a welder? There are many reasons to steer clear of a career change, but we’ve got 10 great reasons for making the switch into a welding career.

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https://www.uti.edu/blog/welding/gmaw-mig-welding

This article from Universal Technical Institute answers many of the basic questions surrounding the GMAW welding process.

This source provides a basic intro into the the terminology associated with GMAW. Everything in this article is relevant to anyone who wants to learn about the GMAW process and it's capabilities.

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Gas metal arc welding (GMAW), also known as wire welding, is one of the most common types of welding. In the GMAW process, an electric arc is formed between the metal and a wire electrode, applying heat to the metal pieces. This action melts and fuses the parts together to form a permanent bond.

As we covered in our history of welding blog, the GMAW welding process emerged in the late 1940s when a continuously fed electrode wire replaced the tungsten electrode in the gas tungsten arc welding (GTAW) process. It quickly became popular because it was more cost-effective than GTAW. Today, GMAW is used in industries ranging from construction and manufacturing to car racing and vehicle production.

Another term for GMAW is metal inert gas (MIG) welding. In the MIG and GMAW processes, a continuous solid wire electrode travels through the welding gun along with a shielding gas, which protects against contaminants in the air. This welding process can be used on both thick and thin sheets of metal, as well as aluminum and other nonferrous materials.

Types of GMAW Welding

When it comes to GMAW welding, there are a few different techniques that can be used to transfer weld metal from the arc to the base metal. These transfer modes are:

Short Circuit

The coldest form of GMAW welding is short circuit, which uses low voltage. The welding wire touches the metal, electricity goes through the gun and a short circuit is created. The effect is a wet metal puddle that quickly solidifies and fuses the materials together.

Spray

In a spray transfer mode, wire gets melted into fine droplets that get sprayed or misted into the weld joint. This is a constant voltage process that uses a high heat input and sends a constant stream of weld metal from the arc to the base material.

Globular

The globular transfer method is similar to the short circuit method. An electrode wire arcs and touches the base material. However, there is a higher heat input and the wire is heated for a longer period. This creates a larger weld puddle, which collects at the tip of the gun and drips into the joint.

Pulse Spray

The pulsed spray transfer is similar to the spray arc method but modified to remove potential disadvantages. The welder will pulse the voltage many times per second, allowing a droplet to form at the end of the wire that gets pushed across the arc into the puddle. It is the most functional and flexible transfer time but can be the most expensive as it requires a high-end MIG welding machine.

What is GMAW Welding Used For?

GMAW welding has many applications in some of the world's biggest industries and can be used for:

Manufacturing

Automotive maintenance and production

Construction

Aerospace

Pipe welding/pipe joints

Shipbuilding

Custom fabrication

Railroad track repair and construction

Underwater welding

The versatility of GMAW welding makes it a popular choice among locations ranging from small repair shops and businesses to large industrial facilities.

Advantages of GMAW Welding

A number of advantages exist for those using GMAW welding, making it one of the most widely used welding processes:

Easy to learn: Compared with other welding processes, GMAW welding is considered simple to learn and is a one-hand operation.

Versatile: GMAW welding can be used to weld a range of metals and alloys. There is a range of filler wire electrode materials, allowing for a range of welds.

Less cleanup: A shielding gas protects the arc during the welding process, meaning there is minimum spatter and slag production and less cleanup after the job is done.

Control: There are a number of settings on GMAW welding machines that allow users to control the polarity, wire speed and amperage.

Efficient: Not only is GMAW welding efficient when it comes to cleanup but also the one-hand operation helps improve control, which increases welding speed and automation while making it easier for the welder.

Disadvantages of GMAW Welding

While there are many pros to GMAW welding, it's also important to know what some of the cons might be:

Cost: The cost of a GMAW welding machine is relatively high upfront with the need for proper maintenance and replacement of parts.

Indoor-only use: GMAW welding machines are not built to be portable. Wind can blow away the shielding gas that is necessary to protect the arc, making it an unsuitable process for the outdoors.

Burn-through: There is the potential to burn through materials that are less than 0.5 mm thick, making the process a less suitable choice for use with certain thin metals.

Limited welding positions: High heat input and fluidity of a welding puddle that comes with a GMAW welder makes vertical or overhead welding difficult with the spray transfer mode.

How Does GMAW Welding Work?

Now that you know some of the uses and types of GMAW welding techniques, here are more details about the process.

GMAW Welding Process

The GMAW welding process happens when an arc is created between a wire electrode and the work piece, which melts them both to form a pool. The electrode is continuously fed and a shielding gas is used. The process is considered semi-automatic since wire feed and arc length are controlled by power, but travel speed and positioning are controlled manually.

To be successful, welders must master how to properly guide and clean the gun and optimize the voltage, flow rate and wire-feed rate. The travel speed a welder employs will influence the quality and shape of the weld. GMAW welders need to judge how the weld puddle size relates to the joint thickness in order to determine the correct travel speed without getting out of range of the welding procedure limitations.

Gases Used In GMAW Welding

Shielding gases are required for GMAW welding as they are used to protect the weld pool from contaminants in the air. The most common types of gases used during the process are argon and helium, which are both inert gases. This means they will not undergo chemical reactions.

However, active gases such as carbon monoxide can also be used. This is called metal active gas welding. Some welders combine active and inert gas together.

Inert, active and a combination of the two all protect the weld pool from contamination while providing unique penetration profiles.

Power Sources for GMAW Welding

Constant voltage power sources are used for the majority of GMAW welding and other semi-automatic processes. The power source provides constant voltage to the arc length during the process. There is a self-correcting arc length feature that helps produce stable welding conditions.

GMAW welding processes operate with reverse polarity when the wire electrode is positive. This is because more heat is generated, which helps reduce the chance of defects from a lack of fusion.

Tools Used

Some of the basic tools used for GMAW welding include:

Safety equipment like auto-darkening helmets, gloves and protective clothing are also used during GMAW welding.

GMAW Welding FAQs

What Does GMAW Stand for in Welding?

GMAW stands for gas metal arc welding. The term is representative of the process.

During the GMAW welding process, an electric arc forms between the electrode and metal to melt metal pieces together. The process also requires a shielding gas to protect the weld pool from contaminants.

What Does MIG Stand for in Welding?

MIG welding stands for metal inert gas welding. "Inert" defines the type of shielding gas used during the process.

Is GMAW the Same as MIG Welding?

GMAW and MIG welding are the same, and the terms are used interchangeably.

What Is the Difference Between GMAW and SMAW?

The shielding agent is the primary difference between shielded metal arc welding (SMAW) and GMAW welding. As previously mentioned, GMAW requires a shielding gas.

However, SMAW, also known as stick welding, uses a flux-covered electrode connected to a power source to create a weld. As the flux around the metal electrode heats up, it melts and produces a gas shielding agent, removing the need for a separate gas source.

What Is the Difference Between GMAW and MAG Welding?

MAG welding stands for metal active gas, so the only difference between MIG and MAG is the type of shielding gas that is used.

GMAW Welding Classes

In the Welding Technology program at Universal Technical Institute (UTI), students learn GMAW processes, equipment and applications in courses like Gas Metal Arc Welding I and II and Welding Applications. ¹ Students learn skills that include:

How to set up and use GMAW equipment and the required welding accessories

Modes of metal transfer

Different gases available to shield a weld

How to produce groove-style joints and steel fillet welds in the horizontal and flat planes

Basic maintenance of a GMAW-style welding machine, including gas hookup and wire spool replacement

How to perform overhead and vertical welds

How to change out whips/guns, correctly maintain a GMAW machine, set up different shielding gases and replace rollers

How to build specific projects and perform various weld types in all positions

UTI students are also taught welding safety, blueprint basics and mathematics used in fabrication. Brian Masumoto, a welding instructor at UTI Rancho Cucamonga, says the main advantage of UTI's program is the breadth of instructor experience.

"Our instructors have 70+ years of experience in welding and fabrication," Masumoto says. "As instructors, we find out what type of welding career the students want to get into and apply what's in the curriculum to that specific job."

Welding Program Locations

Students aren't only taught about GMAW at UTI. They learn about the three other major arc welding processes when they choose to attend one of these campuses nationwide:

Whatever location you choose to attend, you'll receive the hands-on training and experience you need to pursue an entry-level job in the industry. Click the links above to find out more about each individual campus.

Find out more about the Welding program offered at UTI by requesting more information online or by calling us at 1-800-834-7308.

Universal Technical Institute of Illinois, Inc. is approved by the Division of Private Business and Vocational Schools of the Illinois Board of Higher Education.

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What Is GMAW Welding (MIG) & How Does it Work? | UTI

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Gas metal arc welding (GMAW): one of the most common welding processes, utilized across various industries. Interested in how it works and how you can learn it? Check out our blog post linked here!