Gas Tungsten Arc Welding
GTAW in welding is Gas Tungsten Arc Welding, it is one of the welding types like others SMAW, GMAW and FCAW. GTAW (Gas Tungsten Arc Welding) or TIG (Tungsten Inert Gas) is a welding process which applies a non-consumable tungsten electrode for performing welds.
What is the Process of GTAW?
In GTAW, metals are joined by heating process using a non-consumable tungsten electrode and metal piece. It may or may not use filler metal; it mainly depends on the design of joints. The release of inert gas (argon, helium, or a mixture of both) shields the molten metal. It protects it from atmospheric contamination. The temperature of weld pool can rise to 2500°C (4530°F).
What are the Applications of GTAW?
TIG welding or GTAW can be applied on almost all metals and metal alloys available currently. The applications of GTAW is as follows:
- The aerospace industry for manufacturing space vehicles uses mainly Gas Tungsten Arc Welding.
- It can weld small diameter, and think-wall tubing, and its good example is bicycle industry.
- GTAW is first option for making first pass or root pass welds for pipes in piping industry.
- The repair and maintenance industry employs it.
- TIG welding is highly resistant to corrosion and cracking of weld joints, results in long lasting welds.
What are the Disadvantages of GTAW?
Some of the GTAW disadvantages are as follows:
- GTAW cannot produce good weld in bad weather conditions due to difficulty in shielding of weld zone.
- In TIG welding, it is a big risk of contamination of weld metal if not proper shielding by filler metal.
- There is a change of porosity due to leakage of coolants from water-cooled torches.
- GTAW produces less deposition rates in comparison to Shielded Metal Arc Welding process which uses consumable electrode arc.
- TIG welding can weld only in horizontal or flat welding positions.
- The equipments of GTAW are costly.
What is a TIG welder used for?
The process uses a non-consumable tungsten electrode that delivers the current to the welding arc. The tungsten and weld puddle are protected and cooled with an inert gas, typically argon. TIG welding is similar to oxy-acetylene welding in that you use a filler material for build-up or reinforcement.
What is better MIG or TIG welding?
The major 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). … The technical names for these are metal inert gas (MIG), and tungsten inert gas (TIG).
Why do we use TIG welding?
It also can increase the welding speed up to 40%. Helium is also commonly used to weld stainless steel and copper. The argon/helium combination gas is used for a hotter arc in welding aluminum and aluminum alloys. It is also used in automatic welding applications.
What is the most common polarity used in TIG welding?
Direct current electrode negative (DCEN) (straight polarity) is used most commonly to weld stainless steel and ferrous metals. AC current, with the addition of high frequency, is most commonly used for welding some nonferrous metals such as aluminum and magnesium
What metals can be welded with TIG?
TIG can be used to weld copper, titanium, even two dissimilar metals, and is handy for making tricky welds (e.g. s-curves, or welds on round things).. TIG generates heat via an arc of electricity jumping from a (tungsten metal) electrode to the metal surfaces you intend to weld – usually aluminum or steel.
How hot is TIG welding?
The arc develops intense heat, approximately 11,000°F.” TIG Handbook. Miller Electric Mfg Co., 4 June 2007. “The GTAW process can produce temperatures of up to 35,000°F, The torch only contributes heat to the work piece.”
What is the difference between Tig and Heliarc welding?
Meredith named the process Heliarc because it used a tungsten electrode arc and helium as a shielding gas, but it is often referred to as tungsten inert gas welding (TIG). … Finally, the development of alternating current units made it possible to stabilize the arc and produce high quality aluminum and magnesium welds.