Metal Fabrication and Welding
Metal Fabrication by definition is the building of metal structures by cutting bending and assembly processes. it is a process that involves the creation machines parts and structures from various raw materials.
The Cutting element of fabrication is done by a variety of manual and machine processes, the likes of sawing, shearing, oxy fuel torches, plasma torch as well as laser mill router and water jet.
Bending is also done by a variety of manual and machine ways, hammering hydraulic, electric or manual counter weight press in the form of brake press, pan brake and cnc controlled back gauge presses. oxy and other form of heating are also used to bend and twist steel to desired shapes by hand or assisted.
Assembly is one of the final parts of metal Fabricating, assembly can range from adhesives to threaded fasteners and riveting but the most common practice for assembly is welding, there are many ways is which welding can be done and the technology is constantly changing and allowing more automation into these processes but the most common are:
GTAW (Gas Tungsten Arc Welding) also known as TIG Welding is a process that uses a non consumable electrode (Tungsten) to create an arc and weld pool to which filler wire is added. The arc and Weld area is shrouded and protected from the atmosphere by an inhert gas usually argon.
Tig is used mainly for thinner stainless steel as you have better control over the weld and the heated area but it is slower
GMAW ( Gas Metal Arc Welding) also known as MIG Welding, is a process that uses an automatic feed consumable wire electrode to create the arc and weld metal, as it feeds the wire that creates the arc there is no need for filler wire to be added. the arc and weld area is protected by an inhert gas or gas blend usually argon or argon carbon dioxide blend. this process is much easier and quicker.
Mig is used fairly widely throughout the industry as its simple and fast, used mainly on carbon, stainless and aluminium.
MMAW (Manual Metal Arc Welding) also known as Stick Welding is a process that uses a consumable electrode covered in a flux coating, as the electrode burns the flux protects the weld pool from the atmosphere. process is very widely used for cost and versatility of positions and environments.
Stick is used alot in construction and pressure welding for its versatility, can be windy or wet and doesnt really effect the weld like the other processes. is used mainly on normal carbon steels.