Register now or log in to join your professional community.
The main difference between MIG and TIG welding is that one method uses a continuously feeding electrode and is a very fast way of putting down welds. The other way is a much more fine and delicate welding technique.
difference between Mig and Tig welding is that one process uses a continuously feeding wire (MIG) and the other you use long welding rods and slowly feed them into the weld puddle (TIG). MIG and TIG welding both use an electric arc to make the weld.
iN MIG WELD CONSUMEBLE ELECTRODE DRIVEN POWERED MACHINE IS USED.IN TIS FILLER ROD IS USED ACCORDING TOO THE PARENT MATERIAL.
MIG ( Metal Inert Gas Welding) TIG (Metal Inert Gas Welding)
Gas Metal Arc Welding(GMAW)GMA – commonly referred to as Metal Inert Gas (MIG) – weldingembraces a group of arc welding processes in which a continuouselectrode (the wire) is fed by powered feed rolls (wire feeder)into the weld pool. An electric arc is created between the tipof the wire and the weld pool. The wire is progressively meltedat the same speed at which it is being fed and forms part of theweld pool. Both the arc and the weld pool are protected fromatmospheric contamination by a shield of inert (non-reactive)gas, which is delivered through a nozzle that is concentric withthe welding wire guide tube.OperationMIG welding is usually carried out with a handheld gun as asemi-automatic process. The MIG process can be suited to avariety of job requirements by choosing the correct shieldinggas, electrode (wire) size and welding parameters. Weldingparameters include the voltage, travel speed, arc (stick out)length and wire feed rate. The arc voltage and wire feed rate willdetermine the filler metal transfer method.This application combines the advantages of continuity, speed,comparative freedom from distortion and the reliability ofautomatic welding with the versatility and control of manualwelding. The process is also suitable for mechanised set-ups, andits use in this respect is increasing.MIG welding can be carried out using solid wire, flux cored, ora copper-coated solid wire electrode. The shielding gas or gasmixture may consist of the following:ArgonCarbon dioxideArgon and carbon dioxide mixturesArgon mixtures with oxygen or helium mixtures.Afrox recommends Afrox shielding gas mixtures.Each gas or gas mixture has specific advantages and limitations.Other forms of MIG welding include using a flux cored continuouselectrode and carbon dioxide shielding gas, or using selfshieldingflux cored wire, requiring no shielding.
TIG (Metal Inert Gas Welding)
The Gas Tungsten Arc Welding – commonly referred to as
Tungsten Inert Gas (TIG) – process uses the heat generated
by an electric arc struck between a non-consumable tungstenelectrode and the workpiece to fuse metal in the joint areaand produce a molten weld pool. The arc area is shrouded inan inert or reducing gas shield to protect the weld pool andthe non-consumable electrode. The process may be operatedautogenously (without filler), or filler may be added by feeding aconsumable wire or rod into the established weld pool.The addition of filler is optionalOnly inert or reducing gases can be used as the shielding gasTIG welding is a high quality, versatile and commonly-used processTIG is suitable for welding ferrous and non-ferrous materialsThe TIG process can be run on DC-, DC+, or AC.The TIG process is capable of producing very high qualitywelds in a wide range of materials and in thicknesses up toabout 8 or 10 mm. It is particularly suited to welding of sheetmaterial and for putting in the root run of pipe butt welds.The process tends to be very clean, producing little particulatefume, although it is capable of generating ozone in appreciableamounts and is not regarded as a high-productivity process.OperationDirect or alternating current power sources with constantcurrent output characteristics are normally employed to supplythe welding current. For DC operation, the tungsten may beconnected to either output terminal, but is most often connectedto the negative pole. The output characteristics of the powersource can have an effect on the quality of the welds produced.Shielding gas is directed into the arc area by the welding torch,and a gas lens within the torch distributes the shielding gasevenly over the weld area. In the torch, the welding current istransferred to the tungsten electrode from the copper conductor.The arc is then initiated by one of several methods between thetungsten and the workpiece.Operating ModesThe TIG process may be operated in one of the following modes:Direct Current Electrode Negative (DCEN)Direct Current Electrode Positive (DCEP)Alternating Current (AC).The mode used is largely dependent on the parent materialbeing welded.
