Welding is one of the most important industrial processes for fabrication and repair. It is useful to know the basics about the most important types of welding. You may never pick up a welding torch, but with background knowledge you'll be able to better engage with suppliers and craftsmen when the time comes for a welding repair or new build.
Revolution Paint & Panel maintains a high standard in heavy equipment and truck welding repair. Our specialists are certified and experienced, and our shop can handle very large vehicles. We are equipped with the most modern and efficient tools, ready to be your go-to source for commercial truck repairs, truck body repairs and truck smash repairs. Call us on 07 3266 1387 or email enq@revolutionpaintpanel.com.au and we'll discuss your needs.
Different Kinds of Welding Explained
From the Bronze Age
Welding really got started in remote history, when metals began to be worked with heat. When a blacksmith joins two pieces of red-hot metal by hammering them together, that is known as forge welding. Many different kinds of welding have been used commercially - these are the most commonly encountered today.
Gas Welding
Oxy-acetylene welding - oxygen and acetylene gas are fed to a hand-held torch with control valves. The mixture produces an intensely hot, concentrated flame. A filler rod is used - it is consumed and becomes part of the weld bead. The flame shields the weld as it is being formed, so there is no slag to be chipped off later, making this a clean and efficient process. Gas welding dates from the early 1900s. It can produce welds of very high quality and strength, in ferrous and non-ferrous materials. It is used in applications where its precision and fine controllability are needed. It is also the only practical way to weld when no electrical power is available.
Stick Welding
The first successful form of electrical welding, beginning in the 1920s when welding rods (informally called a "stick") were developed that were coated with a shielding material meant to melt onto the weld bead. The consumable welding rod is clamped in a rod holder, which is hand-held by the operator. An arc is struck between the welding rod and the workpiece. The coated rod deposits a layer of slag on the hot weld bead, protecting it from contamination. Slag must be chipped off when the weld cools, making this a slow process. Stick welding can be used to build large structures. It is best suited for ferrous materials. Stick welding is still in use, generally in heavy applications.
MIG Welding
MIG stands for Metal Inert Gas. Developed in the middle of the 20th century, it is a more exact electrical welding process. A spool of solid metal wire is used as both the electrode and the filler material, fed by a small motor in the power pack through a flexible cable to a hand-held electric welding gun with a copper tip to electrify the wire. An arc is struck between the wire and the workpiece. The welding gun also blows a shielding gas, usually argon, onto the hot weld pool, protecting it from contaminants.
The wire feed and gas flow are turned on and off by a trigger on the welding gun. Setup is required to match the wire and gas to the speed of welding. MIG is used to weld non-ferrous materials and high-alloy steels. When welding ferrous materials, it may be called MAG welding (see below). It needs a clean workpiece, but little post-weld cleanup because there is no slag. MIG is probably the easiest welding process, but making strong welds requires experience and skill.
MAG Welding
This is a newer term for MIG welding on most ferrous materials. The only physical changes are a compatible wire type and the use of CO2 shielding gas - everything else is the same, using the same equipment as MIG. MAG stands for Metal Active Gas.
Flux-Core Welding
Flux-core welding is a variant of MIG (and MAG) welding, where the welding wire is hollow and filled with material that will deposit slag over the weld bead. No shielding gas is used. Flux-core can make good welds, but its primary advantage is that it can be used in windy outdoor environments where shielding gas could be blown away.
TIG Welding
TIG stands for Tungsten Inert Gas. Developed in the 1950s for use in aerospace, it is the most precise welding process in common use, and one of the strongest. It is for non-ferrous materials, particularly aluminium. TIG uses a non-consumable tungsten electrode in an electric welding torch controlled by a foot pedal. The torch blows argon or helium gas to protect the hot weld pool. To form the weld bead, the operator manipulates the torch and a filler rod, depositing an overlapping series of small weldments. The resulting weld bead has been likened to an overlapped row of coins. There is no slag, so it is very clean. TIG tends to be a slow process, so it is usually reserved for use where the best possible weld quality is prioritised.
Spot Welding
A specialised resistance welding process for joining of sheet metal components, used widely in the construction of car and truck bodies. Two arms with tungsten tips are brought together from either side of the workpiece, pressure is applied, and heavy current passes between the tips, creating a spot of weldment at the contact point. Many spot welds are made along the pieces to be joined.
Bringing Welding (and all the rest) to You
Revolution Paint & Panel has very broad capabilities in many different kinds of welding, and all the other processes needed for comprehensive repair of trucks and heavy machinery. Truck welding repair is a steady practice and a major specialty for us.
We can handle very large vehicles in our modern, well-equipped shop - located in Narangba, convenient for large vehicles to reach. Give us a call on 07 3266 1387 or email enq@revolutionpaintpanel.com.au and find out how we can assist you. Our trained and certified staff are ready to make your vehicles look and perform at their best.