Plasma Arc Welding: Faster Than TIG, But Just As Precise
Plasma Arc Welding (PAW) is a welding process that is similar to TIG welding. Like TIG welding, Plasma Arc Welding is precise and clean and both use Tungsten electrodes. The biggest difference between the two methods is that PAW allows the welder to position the electrode within the body of the torch, allowing the plasma arc to be separated from the shielding gas.
The plasma can then be fed through a nozzle, which constricts the arc and forces the plasma out at a much higher speed and temperature. The end result is faster welding with the same degree of precision and accuracy as TIG welding. Any metal that can be welded using TIG, can be welded using a plasma arc. The process is often used to produce high quality joints in the chemical, petroleum, and aircraft industries.
The Concept Behind Plasma Arc Welding
Like other forms of welding, the electric arc is created between the electrode and the metal with PAW. Unlike other methods, PAW relies on two inert gases; one forms the arc plasma and the other shields the arc. Another unique feature of plasma arc welding is that the weld is produced by a combination of the heat obtained from the constricted arc between the tungsten electrode and the constricting nozzle or between the tungsten electrode and the job. Temperatures can be 28,000 °C (50,000 °F) or higher in Plasma Arc Welding.
Because the torch can be adjusted to vary the current, gas flow, and the nozzle size, PAW can be used on many different materials and processes, from very narrow penetrations to very heavy and deep welds. One interesting feature about plasma arc torches is that they can be used either to weld or cut metals simply by adjusting the torch settings.
Advantages And Limitations Of Plasma Arc Welding
Plasma arc welding has only been around since 1954 but it has grown and changed quite a bit since that time. It is now being used on a wider variety of metals than ever before and more uses are discovered all the time.
Aside from being precise, clean, and versatile, PAW advantages include: longer arc lengths and greater tolerances to change in arc lengths and the ability to create deep and high quality welds.
As a more complex form of welding, there are more challenges to this method than other methods. Sometimes 3 gases are required – the arc plasma gas, the shielding gas, and sometimes a third gas is used as a back-purge and trailing gas. But the third gas is only needed for certain materials, not every project.
PAW also requires more specialized equipment than TIG welding and requires the welder to have a strong knowledge of the equipment and the gases.
Learn More About Plasma Arc Welding At Josef Gas
If you are ready to learn more about Plasma Arc Welding, contact Josef Gas online or in person at 201 Basaltic Road in Concord, Ontario. Visit our soon to be newly renovated showroom to see the latest equipment and gear or to speak with one of our team members about PAW.
Advantages and Limitations of Submerged Arc Welding
The names for welding techniques are pretty straightforward…stick welding uses a stick electrode, flux core welding requires a flux core, etc. From a practical naming standpoint Submerged Arc Welding (SAW) is no different. In Submerged Arc Welding, the arc zone is fully submerged beneath a heavy layer of flux material. The process protects the weld from any chance of atmospheric contaminants and eliminates the need for shielding gases.
The Choice For High Quality Welds
Some welding projects require very high quality welds. If that’s the case Submerged Arc Welding (SAW) is what you need. This welding process is commonly used on steel and steel and nickel alloys as well as surfacing applications. It is the preferred welding method for joining plate metal because it creates such strong welds.
The strength of the welds is due to the process itself. SAW uses a continuously fed wire electrode and the weld metal to create the weld pool. Flux is poured directly into the weld pool where it becomes molten and conductive and acts as its own shield protecting the weld site from contamination and the operator from spatter, sparks, UV rays, and fumes. Excess flux gets recycled back into the hopper where it can be reused.
SAW is usually a fully automatic process, but it can also be semi-automatic. Since operators can’t see the weld and make adjustments, they must rely on machinery and parameter settings to manage bead shape, depth of penetration, and chemical composition of the weld metal.
Advantages And Limitations Of Submerged Arc Welding
SAW has both advantages and limitations. It is not suitable for every welding application, but can be extremely effective in certain situations.
- Extremely high deposition rates
- Low skill required
- Easily automated
- High quality, sound, uniform welds
- Deep weld penetration
- High speed welds when thin metal sheets are used
- Little to no fumes, arc light, spatter, or sparks are emitted
- Suitable for indoor or outdoor applications
- Single pass welds are possible
- Little to no edge preparation is required
- Flux is recoverable, recycled and reused
- Not very portable
- Process may be limited to flat or horizontal-fillet welding positions
- Limited to steel/stainless steel, and some nickel-based alloys
- Best for long straight seams or rotated pipes or vessels
- Requires flux handling systems
- Requires post weld slag removal
- Best for thicker materials
Visit Josef Gas For Submerged Arc Welding Supplies
Josef Gas carries a full line of welding supplies and materials. Visit us online or in person at 201 Basaltic Road in Concord, Ontario for all of your Submerged Arc Welding needs! Shop for machinery, electrodes, and more!
All About Stick Welding
Stick Welding, also referred to as Shielded Metal Arc Welding (SMAW) or covered electrode welding, is one of the most popular types of welding. It’s suitable for indoor or outdoor welding, can be used on any type of metal, and is also one of the simplest types of welding, making it among the easiest to master – no wonder it’s so popular!
How Stick Welding Creates The Weld
Stick welding is a manual arc welding process that uses a consumable, you guessed it, “stick” electrode to lay the weld and create the weld pool. The consumable electrode is covered with a flux, which melts as an electric current forms an arc between the electrode and the metal pieces. The flux gives off both gaseous vapors and liquid slag, which both shield the weld from atmospheric contaminants. This eliminates the need for a shielding gas.
Like other forms of flux welding, stick welding leaves that slag on the bead, which must be stripped off once the weld is finished. But, since there is no need for a separate shielding gas, stick welding can be used outside, which makes post-weld clean up worth it.
Advantages And Limitations Of Stick Welding
It’s easy to see why stick welding has always been and remains so popular among welders.
- It’s extremely versatile and simple.
- Can be used on all types of metals and alloys.
- Simple materials and operation.
- Electrode provides its own flux, eliminating the need for shielding gas.
- All position capability.
The limitations of stick welding aren’t many and are similar to the limitations you’ll find with other types of welding:
- Arc stability can be a challenge.
- The flux, arc blow, and/or environment may cause excessive spatter.
- Welds require slag removal.
- Requires more operator skill to provide a good weld.
Shop For Stick Welding Supplies At Josef Gas
Visit Josef Gas online or in person at 201 Basaltic Road in Concord, Ontario for all of your stick welding supplies. We carry machines, electrodes, wires, gases, and all of the necessary equipment welders need!