Many TIG welding torches are used with gas lenses. The advantage is that the lenses provide reliable and uniform welding gas shielding for the weld pool.
During TIG welding or also called argon welding, special importance is given to the speed of flow of the shielding gas, as it directly affects the quality of the welding joint.
When welding without a gas lens, the high or too low speed of argon gas flow leads to the creation of a discharge zone in the area of exit from the nozzle, which contributes to the entry of oxygen into the welding arc zone.
Effect of gas lens on shielding gas flow
The result of air entering the shielding gas stream is the porosity of the weld as well as oxidation (graying color of weld seam).
How Gas lens in TIG Weldin works?
The gas lens has a stainless steel metal mesh. This is the part that eliminates turbulence and creates laminarity for the gas flow (a flow in which the gas moves in layers without mixing and pulsation, which blocks the admission of air into the welding zone).
It must be remembered that for greater efficiency and best results it is better to use a gas lens complete with ceramic nozzles.
Advantages of Gas Lens in TIG Welding
The main advantages of welding with a gas lens are:
Stability and orderliness of argon gas flow to the movement of transverse surrounding air flow.
Improved visibility for welder. Achieved due to the fact that the flow operates at a longer distance. Consequently, the nozzle is at a remote position from the part to be welded and the outreach of the tungsten electrode increases.
Gas lenses make it possible to work with metals that have increased sensitivity to air effects.
Welding at different angles of inclination.
Ability to replace the mesh screen in case of contamination.
Installation of a larger diameter nozzle on the gas lens.
Welding aluminum using a gas lens help to provide a uniform gas blanket for the weld. Thus, giving you a cleaner and better controlled weld bead.
Usually bigger the gas lens size, better the weld cleaning on both sides of weld. Welding with a #8 gas lens with give better and cleaner welds compared to #5.
If you are buying gas lens, buy Furick cups. They are good quality and best reviews.
Conclusion
An important advantage of using a gas lens is the ability to work with materials with special properties.
Titanium material is in demand due to its low specific gravity, excellent corrosion resistance and high strength. At the same time, titanium is characterized by increased chemical activity in relation to the gases contained in the air.
When heated to 350 ° C, the metal begins to actively absorb oxygen. At the same time, titanium oxides are formed, which are characterized by low plasticity and high hardness.
At a temperature of 500 ° C, the active interaction of metal with nitrogen begins. This process is accompanied by the formation of nitrides with properties similar to oxides.
Another gas harmful to titanium is hydrogen. It makes the metal brittle. As a result, even a solid-looking part can eventually split along the weld.
Clean welds using TIG Welding with Gas Lens
But, however, titanium has high chemical reactivity with gases contained in the air (easily combine with oxygen to make brittle titanium oxides). It is in this case that a gas lens will help when welding titanium.
Gas lenses are useful when welding products of complex shape, when welding work has to be performed with an increased distance between the metal surface and the electrode.
It is important to note that gas lenses are necessary when welding parts of complex shape, when access to the part is limited and the distance between the metal surface and the tungsten welding electrode is increased. You can use a gas lens on almost all popular TIG torches.
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