1. TIG vs (MIG & MAG)
1) In TIG welding, the welding torch is held by one hand and the Tig rods in the other, which is suitable for manual welding of small-scale operations and repairs.And it is the most important welding method in pipe welding.
2) In MIG and MAG welding, the welding wire is fed through the welding torch by the automatic wire feeding machine, which makes it suitable for automatic welding, featured with very high welding efficiency and of course it can be used in manual welding.
3) The difference between MIG and MAG is mainly in the shielding gas while the equipment for both welding method is similar. The former is generally protected by argon, which is suitable for welding non-ferrous metals; the shielding gas for the latter is generally argon mixed with some positive carbon dioxide, and it is suitable for welding high-strength steel and high-alloy steel.
4) TIG and MIG are inert gas shielded welding. The inert gas can be argon or helium, but as argon is cheaper, it is more commonly used, so inert gas arc welding is generally called argon arc welding.
2. MIG vs MAG
1) MAG welding is metal inert-gas welding using melting electrodes. In MAG welding, the inert shielding gas (He or Ar) is used as the arc medium and to protect the metal droplets, welding pool and high-temperature metal in the welding zone formed by the molten solid wires. MAG welding is the same as TIG welding except that a wire is used as electrode in MAG welding instead of the tungsten rods as electrode in TIG welding. The wire feeder feeds the welding wire from the spool to the welding torch according to the welding parameters. The welding wire is melted by the heat of DC arc. But the polarity is just the opposite of that used in TIG welding. The shielding gas used is also different, and 1% oxygen is added to the argon to improve the stability of the arc. Like in TIG welding, it can weld almost all metals, especially suitable for welding materials such as aluminum and aluminum alloys, copper and copper alloys, and stainless steel, etc. There is almost no oxidation burning loss in the welding process, only a small amount of evaporation loss, and the metallurgical process is relatively simple.2) TIG welding (Tungsten Inert Gas Welding), also known as non-melting inert gas tungsten shielded welding. Whether in manual welding or automatic welding of 0.5-4.0mm thick stainless steel, TIG welding is the most commonly used welding method. If smooth TIG rods feeding is difficult for you, Fox Alloy Tig rods feeder will help a lot. TIG welding is often used in backing welding of pressure vessels, because of better air tightness & anti-porosity performance in TIG welding.
3) The heat source of TIG welding is DC arc, the working voltage is 10-95 volts, but the current can reach 600A. The correct connection method of the welding machine is DC positive, the workpiece is connected to the positive pole of the power supply, and the tungsten electrode in the welding torch is used as the negative pole. The inert gas, typically argon, is blown through the torch to form a shield around the arc and over the weld pool. To increase the heat input, 5% hydrogen is generally added to argon. However, when welding ferritic stainless steel, hydrogen cannot be added. The gas flow speed is about 3-8 liters per minute. In the welding process, in addition to blowing inert gas from the welding torch, it is better to blow the shielding gas from back of the weld pieces to protect the back of the weld. If necessary, the weld pool can be filled with welding wire with the same composition as the austenitic material to be welded. In welding ferritic stainless steel, type 316 filler metal is usually used. Due to the protection of argon, the harmful effect of air on the molten metal is avoided. Therefore, TIG welding is widely used for welding easily oxidized non-ferrous metals such as aluminum, magnesium and their alloys, stainless steel, high-temperature alloys, titanium and titanium alloys, and other not-easliy-molten metals (such as molybdenum, niobium, zirconium, etc), so TIG welding is generally not used for ordinary materials such as carbon steels and low alloy steels because of lower efficiency and higher costs, unless in some very demanding welding jobs.