What Is Welding & How Does It Work?
Welding is a fabrication process that joins materials, usually metals or thermoplastics, by applying high heat, pressure, or both. As the materials cool, they fuse together to form a permanent bond known as a weld. While often associated with steel and aluminum, welding can also be used with plastics and, in rare industrial applications, engineered wood.
This guide explains what welding is, how it works, the different types of welding methods, safety concerns, and what makes each process ideal for specific applications.
Explore Dimar Manufacturing’s certified welding and assembly services for industrial and custom fabrication needs.
How It Works
In most welding processes, a heat source such as a torch or gun melts the base materials, creating a molten pool that allows for the addition of filler material to form a joint. Some methods utilize pressure alone or a combination of heat and pressure, depending on the materials involved and the desired strength of the joint.
Heat and Pressure Mechanics
In most welding operations, heat is applied using an arc, torch, or laser to melt the base materials. A filler material is often introduced to bridge the gap between pieces, while shielding gases or flux coatings protect the molten pool from contaminants.
Fusion and Cooling
Once the materials reach the proper temperature, they begin to coalesce. As the weld cools, it forms a solid, durable joint. The result is known as a weldment.
Key Benefits of Welding
- Strong, long-lasting bonds for high-load applications
- Cost-effective for small and large production runs
- Compatible with a wide range of metals and alloys
- Excellent for both thick and thin materials
- Clean, professional appearance with proper technique
Welding supports both low-volume custom jobs and high-volume manufacturing operations like those performed at Dimar Manufacturing.
Types Of Welding
Understanding the different types of welding can sometimes be overwhelming. Although each type of weld has its own procedure, many may fall under the same umbrella process.
Tig Welding
TIG welding employs a non-consumable tungsten electrode to produce the weld. An inert gas, typically argon, shields the weld area from contamination. This method is known for its precision and is ideal for thin materials and applications requiring high-quality welds.
Mig Welding
This is also known as metal inert gas. This particular welding technique is used for thick, large materials. It often contains a consumable wire that acts like an electrode and filler material.
Compared to TIG welding, it is much quicker and often results in shorter lead times and lower production costs. A lot of the time, it produces welds that require little to no cleaning and finishing. Although these can be used for more extensive material, these welds are less precise, firm, or clean, like something a TIG weld would do.
Arc Welding
This uses an electric arc to create heat to melt and join metals. A type of power supply makes an electric arc between an electrode that is consumable or non-consumable and the base material using either direct or alternating currents. This type of welding is more of a fusion-based process and can create heat intensities up to around 6500°F.
Pipe Welding
As you may have guessed, this type of welding joins two pipes together. A lot of the time, the specific techniques used include MIG & TIG welding. Pipe welding relates more to metal pipes.
Often, you can find this process used in the construction industry, obviously metal fabrication shops like Dimar Manufacturing, power stations, the water industry, and more.
Spot Welding
This is sometimes referred to as resistance spot welding, and is used primarily for welding two or more metal sheets together by applying a particular amount of pressure and heat from an electric current to a specific weld area. A lot of the time, low-carbon steels are used as a material with this.
Stick Welding
Also known as shielded metal arc welding, is a popular term in the industry because the electrode that welds the metal comes in the form of a stick. Stick welding uses a consumable electrode coated in flux to lay the weld. It’s a straightforward and cost-effective method suitable for outdoor applications and thicker materials.
Tube Welding
This is a significant and integral part of steel processing and has been around forever! Like pipe welding, this is where two components are welded together for the part’s life. It’s often a process to create complex type structures.
Popular Welds
Let’s take a look at some of the more popular welds in the industry.
Metal
A lot of the time, heat and pressure are used over a base material. A shielding gas protects the molten metal from getting any contamination or oxidation.
Plastic Welding
After surface preparation, heat and pressure are applied, and the materials are cooled at the end.
Wood
The material has to be exposed to pressure before using the same heat that the linear friction movement creates.
Welding Test Types
It’s important always to check the quality of a weld. Each testing procedure ensures the quality is top-notch and suitable for the weld.
NDE
NDE, also known as non-destructive evaluation, is used to look at the sophistication of welds and base metal. It’s a simple examination and is popular because it’s a cost-effective solution. NDE can determine material specifics compared to NDT, which we will discuss next.
NDT
NDT, also known as non-destructive testing, inspects components or different assemblies for discontinuities or abnormalities in characteristics without destroying the serviceability of the part or system.
Let’s Get To Welding
At Dimar Manufacturing, our team of certified experts is waiting for your next welding project. For more information on what we have to offer, check out our services page or get a custom quote today.
Frequently Asked Questions About Welding
What is welding?
Welding is a fabrication process that joins materials by melting the workpieces and allowing them to fuse as they cool. It’s primarily used for metals and thermoplastics.
What is TIG welding?
TIG welding (Tungsten Inert Gas) uses a tungsten electrode and inert shielding gas. It offers precise, clean welds and is ideal for thin materials or non-ferrous metals.
What is MIG welding?
MIG welding (Metal Inert Gas) uses a wire electrode and shielding gas to quickly produce clean, strong welds. It’s commonly used for high-volume production and thicker materials.
What is stick welding?
Stick welding, also known as Shielded Metal Arc Welding (SMAW), uses a consumable electrode coated in flux. It’s favored for outdoor and structural applications.
What is arc welding?
Arc welding uses an electric arc to generate heat between an electrode and base material. This high-temperature method is effective for thick metals and structural welds.
What is flux core welding?
Flux-cored arc welding (FCAW) is similar to MIG but uses a tubular wire filled with flux instead of external shielding gas. It performs well outdoors and on dirty or rusty materials.
What gas is used for MIG welding?
MIG welding commonly uses argon, carbon dioxide (CO₂), or a mix of both to shield the weld from contaminants.
What is lift TIG welding?
Lift TIG initiates the welding arc by briefly contacting the tungsten electrode with the base metal, then lifting off. It’s useful for low-frequency environments or sensitive electronics.
What toxic substance is released when welding stainless steel?
Welding stainless steel can release hexavalent chromium (Cr(VI)), a toxic and carcinogenic substance. Proper ventilation and personal protective equipment are required.
What is undercut in welding?
Undercut is a groove that forms along the edge of the weld bead and reduces the strength of the joint. It’s typically caused by excessive heat or poor technique.
What is porosity in welding?
Porosity refers to gas pockets or voids within the weld metal, often caused by contamination or inadequate shielding gas coverage.