Welding might seem like an easy task – heating two parts of a pipe to such a temperature that one part can fit into the other one and once they are cool, they stand inseparably. However, that is not the case and professional welders prove that there is a lot of skill involved in the pipe welding process. Depending on the type of material that the pipe has been made from, there are different techniques and requirements that have to be taken into consideration, all to achieve a perfectly welded pipeline that serves its purpose for a long time. So what is pipe welding, how is it done and what materials can be welded?
The TIG, STT, MIG/MAG and many others pipe welding standards
Welding pipelines is a lot different than what handymen know from their at-home workshops. There are many methods of welding that serve industrial purposes and they are all used for different materials and purposes.
TIG, which stands for Tungsten Inert Gas, is mostly used to weld copper, titanium or two dissimilar metals and it is especially good on weldings at tricky points, likes-curves and around welding. TIG generates heat via an arc of electricity that jumps from an electrode the welded surface and uses a non-consumable tungsten electrode to produce the weld. The weld area is, similarly to the MIG method, protected from oxidation by an inert shielding gas. Some metals require the use of a filler metal in order to weld, but there are also autogenous welds that do not require any additions.
TIG is used in smaller welding points and is usually used whenever there are thin sections of pipes. The process allows much more control over the welding process than techniques such as shielded metal arc welding and gas metal arc welding. The welds made by TIG are strong and high quality, although they require more work than any other welding method.
MIG/MAG
This one is one of the most common welding techniques which uses an external gas to protect the welding point from environmental factors, such as oxygen. While MIG stands for Metal Inert Gas, MAG stands for Metal Active Gas. The difference here is that MIG uses only inert gases or gas mixtures, such as argon and helium. MIG is mostly used for welding aluminum and other non-ferrous metals, such as stainless steel, magnesium, copper, and nickel. MAG, on the other hand, has been developed for welding steel.
STT welding, otherwise known as Surface Tension Transfer process, is a great improvement compared to older pipe welding methods. The welding current in STT welding is set automatically, which makes the process safe for the pipe. The STT method makes the welding time shorter than ever before. The fact that the arc current is set automatically and can be controlled eliminates the violent and explosive nature of traditional welding techniques, which in turn gets rid of rough arc and splatter around the welding point.