GTAW or gas tungsten arc welding is one of the most popular methods of welding materials.
Specifically, GTAW is the process of joining metals with a non-consumable tungsten electrode.
It requires a special inert gas environment, in particular, argon.
Also, GTAW is the other name for TIG (tungsten inert gas) welding.
Principle of Operation
The welder melts the edges of the product and filler metal by an electric arc.
The electric arc burns between a non-consumable tungsten electrode and the product.
In such a case, the worker uses an electrode of either pure or activated tungsten.
Besides, a weld pool can contain a filler metal too.
After that, the liquid metal of the weld pool hardens as the arc moves.
As a result, you get a weld that connects the edges of the parts.
Finally, the nozzle feeds special gases which displace oxygen and nitrogen, protecting the metal seams.
In comparison with the other welding methods, tungsten inert gas welding has the following pluses:
• it allows to obtain high-quality welds for almost all metals and alloys (including hard-to-weld and dissimilar, for example, aluminum with steel);
• good visual control of the weld pool and arc;
• due to the absence of metal transfer through the arc, there is no metal spatter;
• practically no surface treatment is required after welding;
• as in the case of MIG (metal inert gas) / MAG (metal active gas) and MMA (manual metal arc) welding processes, GTAW welding can be performed in all spatial positions;
• as in the case of MIG/MAG welding, when welding GTAW there is no slag, whiсh means that there are no slag inclusions in the weld metal.
The welders name the following disadvantages:
• The complexity of working on the street during windy weather. The wind blows shielding gas from the welding zone; you can fight this by using barriers or by increasing the gas supply, which will lead to its increased consumption;
• Better metal preparation before welding versus MMA is required;
• The design of the burner makes it not very convenient to weld parts at an acute angle;
• After ignition, a trace remains outside the weld zone that needs to be cleaned; it should also be noted the low productivity of the process and the high cost of the power source (as compared to welding with the consumable electrode.
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