Welding

Spot welding machine

Conventional Welding machine

Spot welding of sheet metal

Spot welding of a bracket

Welding is a method of joining metal parts permanently and strongly with minimal setup costs. Three popular types of welding include:

• MIG welding - an arc is created between a consumable wire electrode and a work piece. In MIG welding the electrode melts within the arc and is deposited as filler material. A shielding gas is provided throughout the process to protect the weld from atmospheric contamination during solidification. Shielding is provided by an inert gas, hence MIG for Metal Inert Gas.
  
• TIG welding - an arc is created between a non-consumable tungsten electrode and the work piece. Filler material is supplied via a wire or rod. Shielding is provided by an inert gas, hence TIG for Tungsten Inert Gas. 
  
• Spot welding - contacting metal surfaces are joined by the heat obtained from resistance to electric current flow. Workpieces are held together under the pressure exerted by electrodes and then an electric current is applied.
  

Example of parts that use welding during their manufacture include metal boxes, trays, brackets, mechanisms, tanks, etc. Welding allows to join edges in almost any shape configuration. Tooling used during welding are generally stock items, though custom jigs are used at times.

Cost optimization options for welding include reducing the total weld length, reducing the number of weld joints and designing shapes that are practical to work hold.

Welding Design Considerations

• MIG welding can join most types of metals.
• TIG welding is suited to thin metals, exotic materials and small parts for high quality precision welds.
• TIG welding often is used to join aluminum, magnesium, stainless steel, titanium and nickel alloys.
• Spot welding is among the lowest cost welding methods.
• Spot welding usually joins aluminum, brass, cast iron, mild steel, stainless steel and magnesium.