Many consider welding to simply be an activity that requires multiple pieces of metal to be joined together by some form of heat. This is typically true. The application of heat to metal allows them to have enhanced malleability which also allows them to be joined together in a single joint – don’t forget that when the heat is applied, one must also apply pressure to the pieces of metal to make sure that they are joined. Welding has been around for quite some time. Before it was known as the “welding” that we know it as it was called “forge welding” which basically meant that 2 pieces of metal were being joined together.
In short, forge welding required the welder to use an open flame to develop enough heat to make the metals that were meant to be welded malleable. Eventually, this method of welding began to die out. As energy sources were harnesses gas and electric welding methods were harnessed to keep the welders safer in the workplace. More tools than we care to think about have been created by welders. This is because of the wide applications that welding has in construction as well as in everyday life.
Welding is a process that has a wide variety of application to everyday life. It’s important to keep in mind that these applications also require that each of the welding processes be diversified.
The most widely known welding types are Electroslag, Arc, Gas Metal-Arc, Plasma Arc, Metal Inert Gas, Gas Tungsten Arc, Shielded-Metal Arc, Tungsten Inert Gas, and Submerged Arc. However, these are all Arc welding processes – there are a variety of processes including,
- Oxyfuel Gas Welding
- Resistance Welding
- Solid-State Welding
As well as a few others. Below, we’ll go over each type of welding (the broad type) as well as a few subcategories.
What is Arc Welding?
Arc welding is a fusion process that uses an electric arc from power supply (either AC or DC) that creates a heat around 6500 degrees Fahrenheit which melts the metal at the joint. One can guide an arc mechanically or manually along the joint.
Metals used in arc welding react to the nitrogen and oxygen in the air when they’re heated to the degrees possible by the arc. To help prevent the negative effects of the reaction to the metal, a slag (protective shielding gas) is used to reduce the weld’s contact with the air. The weld is finished to once it cools and solidifies.
Video credits to Weld.com. It’s a very thorough introduction to arc welding.
Arc Welding sub-types
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What is Oxy-fuel Gas Welding?
Oxy-fuel welding is a blanket term uses to describe welding processes that use the combustion of both Oxygen and fuel to produce enough heat for fusion welding. Oxy-fuel processes entail the use of a flame (that’s produced near the end of the welding torch) to melt the parent metal with / without filler metal. The actual fuel and gas are placed inside of a chamber where they’re mixed (this chamber is a part of the welding torch.
With oxy-fuel welding you may relinquish a few of the benefits that you get with arc welding but, you receive some of the following benefits:
- Welders get decent control over the heat input, filler metal addition, and temperature (all independently)
- The flame chemistry can be altered from carburizing through neutral to oxidizing.
- Equipment is relatively inexpensive and portable
Oxy-fuel Welding sub-types
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What is Resistance Welding?
Resistance welding is the process of joining metals through the application of pressure and a current for a period. The advantage of resistance welding is that one doesn’t need anything other than the materials used to create the weld (it’s an economical choice).
Resistance Welding sub-types
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What is Solid-State Welding?
Solid State Welding is a joining process that doesn’t have either a vapor or liquid phase. Not only that but it uses pressure and doesn’t have to use temperature. For solid state welding to take place the cohesive forces between atoms and metal are used.
Solid-State Welding sub-types
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