Welding is the process of joining two pieces of metal or thermoplastic, by the method of partially melting them and then fusing them together. In this regard, it is very different from other common joining methods like brazing or soldering. While those methods rely solely on a filler material to form the bond between two objects, welding instead creates a direct bond between the objects to be connected by forcing them to fuse together at high temperatures. Filler materials can also be added to increase the strength of the weld, but the main characteristic of welding is that it makes a direct change on the base material itself.
Heli-Arc: TIG Welding
TIG is a form of arc welding, which means that the weld is created by using a powerful electric current to generate the required heat. In this particular process, a tungsten electrode is used to provide the power supply. Non-consumable implies that the tungsten itself does not participate in forming the weld; instead, a separate rod of filler material is used in addition to the electrode.
Considering the wide variety of uses for welding, the process has seen several refinements and developments over the years. Welding is now a highly specialised field, with the specific method chosen depending heavily on the raw materials being used and the desired end result. A very popular method is Gas Tungsten Arc Welding (GTAW), or Tungsten Inert Gas (TIG) method.
Final Words on Process
The final requirement of the process is an inert gas. Gases like helium and argon are generally used, and their role is to provide a protective barrier around the weld area so that atmospheric contamination does not take place during the welding.
The advantages of this process are several; firstly, this process grants a lot of control to the operator, which allows him to create welds of greater strength and higher quality. This degree of control also allows him to create more specific or custom welds, something that is not easy to do with competing processes. The main advantage of this process however is the sheer variety and combination of weld and filler materials that can be used, including non-ferrous metals like aluminium and magnesium.
Most other arc welding processes use the filler material as the electrode as well; and while this makes it more efficient it also limits potential choices, since not all filler materials have the desired properties to act as an electrode. The separation of the electrode and filler material that is a key part of TIG, in addition to the higher quality welds that can be formed by this method, thus makes it very useful process in industries where quality is paramount.
In fact, the biggest user of the TIG welding process is the aerospace industry, where it is applied during the construction of space machines. The strong, durable welds formed by this method are highly resistant to corrosion and as such are used to join critical components together. On a more mundane level, TIG is often the preferred method for repair welding, again because of the wide variety of filler materials that can be applied during the process.
Although it does have its share of disadvantages, like being a slow process that requires a highly-skilled operator, it still plays an important part in the industry where it is commonly used for both steel and non-ferrous welding.
How To Operate A TIG Welding Rod
People have always wanted to find ways to easily and efficiently connect separate pieces of metal, but until electricity was discovered — this task was not possible to accomplish. Electric energy changed the game completely, and welding is nowadays a backbone of the modern metal industry. In other words, we can quickly connect separate segments in a convenient manner.
And our techniques and technology are so advanced that the actual places of connection are almost invisible. TIG welding is one of the methods which allows for this type of quality and seamless connectivity, but operating a TIG welding rod is not as easy as it may seem at first.
Different Types Of Tungsten Electrodes
Electrodes are an integral component of the welding process, and they significantly affect the quality of the end-product. When it comes to TIG welding, tungsten electrodes are in use with this particular method, and they can come in several different versions. Tungsten itself is a highly durable material, and it can even sustain temperatures of 3.410º C without melting.
In combination with power supply, an electric arc is formed, and this field enables the filler metal to connect two pieces of metal. Some electrodes contain 99,5% of tungsten, and they are called pure tungsten electrodes, and their code color is green. Other types include slightly lower amounts of this rare material, typically 97.3% and the rest is “occupied” by lanthanum, thorium, or some other similar metal.
How To Handle A Tungsten Welding Rod
One of the essential advantages of TIG welding comes from the fact that this method does not produce smoke of fumes as side effects. Which means that operators can clearly see the surface that they are working on. Due to this visibility, and the fact that a TIG welding rod can be held like a pen, workers with sufficient experience can easily create intricate work and produce welds of impressive quality and aesthetic value. Clean and precise, these welds are durable as well, and different sub-categories of tungsten welding are present in the current market, including dabber, hot wire, or pulsed-current TIG welding.
TIG welding is rising in popularity and it is also known as Gas Tungsten Arc Welding (GTAW). In welding industry, many professionals refer to this welding as Heliarc too as it was given to the process conducted by Linde’s decades back. The arc is Tungsten electrode helps start the arc, which is already shielded by inert gas, and the filler rod is foddered into the weld puddle respectively. The gas shielding is required to protect the molten metal from all sorts of contamination and amperages are resourced during TIG welding operation.
Although MIG welding has proved to be a better welding process than TIG, TIG is apt for precise weld and is usable even at lower amperages when welding thinner metals. You can also apply TIG welder on exotic metals. As per the expert comments, TIG welding is a high quality welding process, which ensures precision. Unlike MIG welding, it takes time to learn TIG welding process.
Elementary Facts of the TIG welding process:
- Non-consumable tungsten is used at the time of welding process
- A number of shielding gas is used, which involves argon and helium
- TIG welding is easily processed on thinner metals
- Capable of high-quality results, superior welds
- Welds can be made without filler metal too, which is quite unlike of those co-existing welding processes
- TIG welding allows the welder to have precise control of welding element, i.e. heat.
- TIG welding generates low distortion
- And, it leaves no splatter or slag
Some Benefits of TIG Welding Process
- TIG welder welds more alloys and metals than the other processes
- TIF welders are normally used to weld stainless steel, steel, aluminum, chromoly, magnesium, nickel alloys, brass, copper, bronze, and gold even. This is a very effective welding process for bike frames’ welding, wagons, door handles, lawn mowers, fenders and many more.
- Results in high quality, unsoiled welds
- With incredible control of puddle and arc, TIG welding lets you create unsoiled welds when look counts. And, this is because the heat input is utterly controlled by pressing the foot pedal, just as similar to car driving. Moreover, this very welding process grants you to cool down and then again heat up the weld puddle in order to make the whole process result in precise welds. This is why, for cosmetic welds such as automotive and sculpture welds, TIG welding always makes a better choice.
- Only one shielding gas (Argon) is used for all application
- Since Argon is usable to TIG weld all metals of any thickness, thus you need only one gas to complete all your welding projects saving a lot on your production cost.
- It welds in all positions
- Unlike MIG welds, TIG welds can be made in all possible positions such as horizontal, flat, vertical and even overhead. This is apt for welding roll cages and confined areas alike.
How To TIG Weld
One of the reason this welding process is very difficult to learn is that the welder has to use a smaller arc length; he has to be able to have a very steady hand. If they aren’t able to keep a distance between the electrode and the piece they are working on, the piece can become contaminated and there can be problems with the weld.
This is also a two-handed process because you have to be able to hold the torch in one hand and feed a filler metal into the space that you are welding. You can see that this is a very intricate process and one that requires high skill.
Tig welding is a process where a tungsten electrode is utilized to heat and fuse the metals to be welded. The gas is used as a shield around the weld that protects the weld pool or puddle from atmospheric contaminants eliminating the need for any flux.
How to Start
To learn how to Tig weld you need to set up the machine and associated parts such as the gas and torch, plus have on hand the filler rod for whatever metal you will be welding. As there are many types of tig machine, the setting up can best be found in the owner’s manual. Before you start, check that the tungsten electrode is grounded to a point. This should be done on a grinder so that the grinding is done as a straight grind, meaning that the grind marks are running the length of the electrode and not around it.
To start welding, hold the torch at an angle of between 70 and 80 degrees, make sure you don’t touch the work with the tungsten electrode as this can cause contamination. Hold the tip about 1/4 – 1/8 Th inch above the work to activate the arc. To begin with, practice controlling the weld “puddle” at about 1/4 inch wide.
Once you have control of the puddle, you can introduce the filler rod to the weld. This should be added by way of a dab and not a continuous feed. The process should be smooth and controlled, this may take some practice. Always use the push method when using the Tig torch.
Tig welding is a very clean process compared to other methods. There is very little fume or smoke unless the base metal is contaminated. There is no slag or splatter associated with this which makes it most desirable for situations that require a cosmetic look such as in metal artwork or furniture for example. Once you learn how to tig weld you will be convinced that it is the most superior of all welding techniques.