If you are new in the welding field and want to know the advantages of TIG welding than first you need to understand the basics of the TIG welding process. After a proper understanding of the process, you will be able to understand the advantages of TIG welding. Controlling of TIG welding process is hard at the beginning but it will pay off once you get expertise. After understanding the TiG welding advantages and disadvantages you will be able to decide whether the TIG process fulfills your welding requirement or not.
Applications of TIG welding
- This process can be used to weld steel, chromyl, brass, bronze, magnesium, nickel, titanium, aluminum, copper, stainless steel, and other alloys.
- If you need high-quality weld then TIG is the most suitable process. It is used in high pressure holding equipments like pipelines, vessels, and airplanes. It is also used in the automotive and art industry.
- This process can be used to weld in any position like horizontal, vertical, and overhead.
In case you may need a Tig welding helmet.
TIG welding process
TIG stands for tungsten inert gas welding. American welding society calls this process gas tungsten arc welding or GTAW. Sometimes it is also called Helarc welding. TIG welding is an electric arc welding process. TIG welding uses a tungsten electrode. Tungsten has an extremely high melting point of 3422’C. When you do TIG welding, the electrode gets hot but it does not melt and never become part of your weld. You can adjust the length of the tungsten electrode stick holder by loosening the end cap of the holder.
Two metal pieces that you need to join are called base metal. TIG welding works by melting the base metal and base material melts your filler metal. Filler metal adds separately by hand in the form of a filler rod. If you want to add filler metal in TIG weld than use a filler rod which is just a rod of metal with a specific alloy. Make sure filler rod material is compatible with the base metal.
Heat is generated by an electric arc that forms between the base metal and the tungsten electrode. You can control the amount of heat by controlling amperage through foot puddle or thumbwheel on the torch. You can TIG weld with or without filler metal.
TIG welding requires three things, heat, filler metal, and shielding gas. Molten metal is protected by shielding gas. This gas is usually Argon or helium. Shielding gas protects the molten metal from oxidation due to reaction with oxygen, water vapor, or other gases in the atmosphere. Without shielding gas you will burn the tungsten electrode, contaminate the welded area, and would not get any penetration into the workpiece.
This shielding gas is stored in a high-pressure cylinder. Pressure reduces to usable level by the regulator on the cylinder. Mostly 15-25 cubic feet per hour flow rate of shielding gas is required.
TIG welding requires every piece of the base metal to be very clean. This process can weld stainless steel, nickel, titanium, aluminum, copper, and their alloys.
For most metals, the current used is direct current. In DC TIG welding tungsten electrode is usually negative and the workpiece or base metal is positive. In DC TIG welding negative electrode puts most of the heat on the workpiece. It gives deep arc penetration and reduces heat in the electrode. In AC TIG welding positive and negative voltage switch back and forth between the electrode and workpiece. It puts more heat on the electrode. AC TIG welding is used to weld aluminum.
Advantages of TIG welding
1. High quality and clean weld
TIG process produces high quality and high purity weld compare with other types of weldings because it offers great control over the weld area. You can control the level of heat input as well as the speed of the filler rod. There is no need for any finishing process after welding. High quality and complete control over weld place this benefit at top of advantages of TIG welding.
For maximum weld quality tungsten electrode and base metal must be free from oil, moisture, dirt, and other impurities. Because these cause weld porosity and consequently a decrease in weld strength and quality.
2. TIG is best to weld critical joint more precisely
TIG weld offers the best solution to weld critical joints, where exceptionally precise welding is required. The Tungsten electrode in itself has a pen-like shape. So, it allows the welder to use it in restricted and narrow spaces. Moreover, it also enables the welder to fix his project with various positions like inclined, down the head, and overhead.
Choose an old school welding helmet to work in overhead or congested spots.
3. TIG welding process is more versatile than any other
TIG welding process can be used to weld a wide range of metals like stainless steel, chromium, aluminum, nickel alloys, magnesium, copper, brass, bronze, and even gold.
The most cited advantage of TIG welding is its excellent control over lower amperage rating like 10-200 amps, which allows the welder to work on a thin piece of metal. It is also possible to weld thick metal by using high amperage and multiple passes. If your base metal is 1 /4 inch thick you can use 200 amps to weld it.
The TIG welding process can be used with or without filler wire. Welding without a filler rod is called fusion welding. In this process, we fuse the separate pieces of the base metal by stealing some of each piece to fill in space between them.
4. TIG welding offers complete visual accuracy
No flux is required in TIG welding because shielding gas protects the welding puddle from oxidation and contamination. There is no slag to block your view and a transparent arc enables the welder to clearly observer electrode, base metal, and weld puddle.
5. There are no spatter and less smoke during TIG weld
TIG welding works by melting the base metal and base material melts your filler metal. In this way, only the necessary amount of filler metal is added in the welding puddle. So, there is no spatter problem at all.
Burning of insulation, paints, oil, or other contaminants on the base metal produces smoke or fumes in the welding process. Before TIG welding you have to clean base metal from oil, paint, lead, and grease for the better quality weld. So, during welding fewer amounts of smoke or fumes produced.
6. Argon shielding gas is enough for all TIG welding application
You can use argon to shield all metals types and thicknesses. You only need one type of shielding gas to handle all of your TIG welding projects.
Disadvantages of TIG welding
If we compare TIG welding with other types of welding processes then we also observe some disadvantages that come with TIG welding. Before you purchase a TIG welder you must also consider the following disadvantages of this process.
1. Time-consuming due to slow deposition rate
If you need to do welding quickly then TIG is not a good choice. TIG process no doubt offers an excellent quality of weld but you have to compromise on time. TIG welding is slow due to the slow deposition rate of filler metal.
2. There is a need to clean the base metal before TIG welding
Welding of dirt metal with the TIG process will result in a weaker weld quality. To get the best quality of weld you have to clean the base metal surface from oil, paint, lead, grease, and corrosion. You have to use a right-angle grinder or metal surface cleaner to clean base metal which results in extra effort and money consumption.
3. You need a high level of welding skill to get the best result from TIG welding
A TIG welder has to use his both hand and one of his feet to perform welding. It is harder for beginners to focus arc with such engagement of body parts. So, it is advisable that if you are new in the welding field then take a start with an easier process.
4. TIG-welded metal pieces cannot take-apart without destroying
It is difficult to take apart metal pieces that have been welded together with the TIG welding process. You cannot reuse the welded metal piece for another application.
5. Labor cost for TIG welding is relatively high
Highly skilled and experienced person performs TIG welding. Moreover, TIG welding is also time-consuming. Both these factors increase the labor cost of your project.