Metal inert gas welding — or MIG welding, as it is known for short — is one of the most common forms of stick welding used today. This popularity stems from the fact that MIG welding produces excellent results with a minimum of effort. An electrical impulse generated by the power source supplies the energy needed to fuse together two or more pieces of metal.
MIG welding utilizes a solid wire electrode, which feeds through the welding gun. This wire melts as it reaches the weld pool, forming the weld joint. MIG welding also relies on the presence of a shielding gas, which protects the weld area from oxidation that would otherwise lead to rust and other problems.
While the central principles of MIG welding haven't changed much in the last several decades, new options have arisen in terms of the power source used. If you would like to learn more about how the power source affects MIG welding, read on. This article will outline three key things to know about MIG welding power sources.
1. Two Main Power Sources Exist
MIG welding power sources can be broken down into two main categories: transformers and inverters. For many decades, transformers were the only choice for those interested in welding. Manufacturers have had nearly 100 years in order to refine transformers to optimize the performance of MIG welding set-ups.
Inverters, by contrast, represent a fairly new option for powering a MIG welding set-up. Inverters were developed in recent decades as computer technology advanced by leaps and bounds. Inverters use computer software to control the energy output, thus allowing automated control of the MIG welding arc for more efficient and uniform results.
2. Inverters Promote Better Welds
Transformers allow welders to create functional, long-lasting welds when working with mild steel. Yet ensuring consistent results becomes more difficult when it comes to welding other metals. Even when working with steel, the results welders get with transformers simply may not be good enough.
One common problem is weld spatter — in other words, droplets of molten wire fly out of the weld area and harden elsewhere on the base metal. To a certain extent, weld spatter is an unavoidable aspect of MIG welding, especially when using a transformer as a power source.
Weld spatter often happens as the result of excessive amperage or insufficient voltage. Even experienced welders have a hard time responding quickly enough to changing circumstances to prevent these issues when working with a transformer. An inverter, on the other hand, can automatically adjust variables to reduce the likelihood of weld spatter.
Furthermore, an inverter can limit weld spatter by varying the waveforms it produces. Pulsed waveforms allow the inverter to control the likelihood and speed of weld spatter. As a result, the welder bears less of the responsibility for limiting weld spatter by varying the wire feed speed.
3. Transformers Are Usually More Durable
Transformers retain one key advantage when it comes to their longevity. Simply put, the simpler nature of a transformer makes it better able to withstand the rigors of daily use. This advantage stems from transformers' relatively longer history. Manufacturers have been able to analyze lifespan data and make changes to promote better durability.
Inverters, by contrast, simply haven't been around long enough to allow such detailed analysis. Of course, future inverters will likely boast much better lifespans than those currently on the market, making them more and more attractive as time goes on. For more information about what it takes to ensure the best results from MIG welding or to get welding work done, please contact the experts at Sam's Welding, Inc.