MIG vs. TIG Welding Robots
MIG and TIG welding are two of the most common types of industrial welding and have both had a great deal of success with robotic automation. Both are types of arc welding applications involving the use of an inert gas in order to shield and protect a weld from contamination. However, that is where their similarities end as they are quite different from each other.
MIG welding, also known as gas metal arc welding (GMAW) for its technical name, uses a continuously fed consumable wire electrode as a filler material. This wire electrode forms an electric arc between the wire and the metal workpieces. The workpieces are fused together due to the melting of the filler wire between them. Integrating a FANUC Arcmate 120ic with a Lincoln Powerwave R350 welding supply can fully automate MIG welding applications.
TIG welding, or gas tungsten arc welding (GTAW) for its technical name, uses a non-consumable tungsten electrode to form a weld arc that then heats and melts two workpieces in order to join them together. A Motoman MA1400 integrated with a Miller Auto Axcess 450 welding supply is a popular choice for automation of TIG welding.
MIG welding robots are best suited for joining thick metals or large objects together. Since this process uses a wire electrode as a filler material, metals do not have to be heated all the way through in order to be joined. This makes MIG robots like the FANUC M-710ic/20L ideal for thick metals because the filler is melted instead of the metal, allowing thicker workpieces to be welded more efficiently and in less time. The use of a filler material also makes MIG welding robots capable of joining dissimilar metals together, providing manufacturers greater flexibility in their operations. MIG robots are best for welding metals with very high melting points, some of which include: aluminum, stainless steel, and mild steel.
TIG welding robots excel at joining thin metals and small, intricate parts together. Metals that are electrically resistant are best for TIG welding applications since they tend to heat and melt at faster rates. TIG robots, such as the FANUC Arc Mate 120ib/10L, offer greater versatility with metal types as they can be used to weld more metals than MIG robots. Some of these types include: titanium, magnesium, copper, and steel.
MIG welding robots are capable of running weld guns continuously, providing greater speed than TIG robots. Their faster speed means increased productivity, particularly with large workpieces.
TIG welding in general is a slow process that takes about one quarter of the weld speed as MIG welding. Automation of TIG welding with robotics helps to reduce the cycle time of this process, but the main focus remains on fine, detailed work over speed.
The automation of both of these processes with robotics increases weld quality, however TIG robots still hold an advantage in this area over MIG robots. TIG robots generally create clean and even welds since they do not typically use a filler material.
With MIG welding robots the use of a filler material increases the risk of spatter occurring during the weld. This could lead to the need for additional steps in order to clean up the workpiece.