TAG & MIG Welding
These two methods are the most commonly used welding processes in the sheet metal and general fabrication industry.
The Tungsten Active gas (TAG) system uses an electrode of tungsten and an inert gas shield of argon or helium.
The TAG process was originally developed for welding magnesium and it is now widely used for the welding of aluminium, copper, mild steel, stainless steel, and a wide range of other metals that are difficult to weld such as brass. TAG welding can also be used to weld Alloy castings such as gear box covers and other various automotive engine and transmission parts. Consumable rods also referred to as filler wire may be used depending on the type of weld and the thickness of weld.
The Metal Inert Gas (MIG) Process uses a consumable electrode of wire form normally in a coil and an inert gas shield of carbon dioxide when welding carbon steel most commonly referred to as argon Co2 mix. The coiled electrode wire provides a continuous feed of filler metal allowing welds of any length without stopping. The inert gas shield eliminates slag spatter and allows for a cleaner and stronger weld. This process is used widely for general fabrications where weld aesthetics are less important. Generally MIG welding is a quicker process than TAG welding.
Spot welding utilises a high current at a low voltage which passes through a spot on two pieces of metal, usually sheet metal, for a short period of time melting the lapped materials together. This process is done using a spot welder. Resistance to the current flow results in localised heat generation which melts the metal between the copper electrodes. The electrodes or welding tongs exert a modest pressure forcing the two metal pieces together at the spot. The weld spot results at the interface.
Projection welding is a modification of spot welding. In this process, the weld is localized by means of raised sections, or projections, on one or both of the workpieces to be joined. Heat is concentrated at the projections, which permits the welding of heavier sections or the closer spacing of welds
Hank Rivet Bushes (Hanksert or Hankbush) provide a simple solution to the problems associated with producing a deep tapped hole in thin sheet materials such as steel, stainless steel, aluminium and plastics. They can be fastened by a simple squeezing operation by hammer or press, thus obviating the need for expensive tooling. When installed they provide a strong anchorage against torsional resistances and pull out loads.