Are you thinking about choosing welding as your career? Want to prosper in the welding industry without any problems?
You will find several techniques you can learn if you are new to welding. And it can also make you confused when deciding which technique you want to go with. It can get difficult for you to find the method which is suitable for you.
We are here to help you out. So if you want to make your mark and polish your skills, you clicked on the right page. We will be talking about FCAW welding today which is a specific type of welding used to weld thick metals.
Contents
What is FCAW welding?
First of all, we have to know what exactly FCAW stands for. FCAW stands for flux-cored arc welding. In the industry, it is also named dual shield welding. This technique is very similar to MAG welding.
It is the most productive semi-automatic welding method. It uses an electrode surrounded by flux which is consumable. Metal is welded by continuously heating it with an arc between the base metal and electrode.
Shielding gas is also required which is supplied from an external source.
Equipment required for FCAW welding
Before going further in the discussion about how it works, first, we will list down the equipment that is required.
Power source
First and foremost, the power source is required to provide the voltage needed for welding. A constant direct current voltage is recommended for this type of welding. The power source should work with the frequency of 50 t0 60 hertz. It should be able to use with a single-phase or three-phase input.
Equipment for Shielding gas
This type of welding can be done without shielding gas as well. But you might be needed a hose for gas supply, gas regulator, supply hose to welding gun, and control valves for certain applications. Shielding gases are used in liquid form and are stored in storage tanks.
Welding gun
Water-cooled or air-cooled, both types of welding guns can be used for this welding. Welding guns are used at maximum current capacity to ensure throughout weld. Water-cooled guns are advised to use with greater than 600 amperes of welding current. Whereas, air-cooled guns are used less than 500 amperes of welding current.
Welding cables
Welding cables are required to connect the welding gun to the power source. These wires are usually made of copper. The cable which is used to connect the welding gun with the power source is named electrode lead.
Weld feed motor
The power supply is needed to drive electrodes through the gun and cable. Weld feed motor gives the necessary power supply. You will find different wire feeding systems in the market. From all these systems, you can pick the one you find most suitable for your project.
How does FCAW welding work?
Now, coming towards the main question “how does it work?”
Heat is produced by the electric arc when the base metal is fused. A tabular electrode is used which is filled with suitable flux material. A properly selected electrode can play an important role in preventing the formation of gas.
FCAW welding method is famous for the flux-cored wires because they have penetrative properties. That is the reason, it can be used outdoors as well. Also, this welding does not require external shielding gas to prevent its weld from the outer atmosphere.
When used on thick metal, FCAW results in slag formation. It should be removed and cleaned properly before the weld gets cold to get a clean finish.
FCAW methods
Flux-cored arc welding can be done in two ways. We will discuss both of them here separately:
- By using external shielding gas
- By using the flux core to protect the weld area
By using external shielding gas
For additional shielding, this process uses flux and carbon dioxide. The shielding gases required for this process are carbon dioxide and the mixture of argon and carbon dioxide.
Carbon dioxide is supplied to the weld from an external source with high pressure. This prevents the oxidation that might happen around the weld. It helps in preventing slag formation as well.
This procedure is commonly used to weld thick metals together. But the presence of strong wind can affect the shielding produced by carbon dioxide. This is the reason that you should be careful of external weather conditions.
Using the flux core to protect the weld area
Here we focus to protect the metal that is welded, from slag formation and toxic gases.
When the welding arc burns, a shielding effect s provided by the filler material.
This method gives a huge advantage while working outdoors. Because it is independent of the weather. You can make it work even in severe weather conditions. The main thing is that here you will not need the external shielding because wind cannot disturb such welding.
The electrodes should be shielded to ensure the safety of arc and molten weld from environmental elements. The mechanical properties of the weld are determined by the chemical composition of the electrode used.
Electrodes used for flux-cored arc welding are shielded with metal and are surrounded by flux core. The flux can be of low alloy metals or carbon steel.
Advantages of FCAW welding
As the most efficient welding technique when it comes to welding thick metals, FCAW welding is highly recommended as used in heavy machine industries. These points will quickly let you know the main features of this technique so you can evaluate it better.
- FCAW welding method is efficient for both indoor and outdoor purposes.
- It is suitable to weld thick metals.
- It provides more flexibility to the weld than other welds.
- It is an all-position welding process. The welder can move the welding gun in all directions and can get a better result.
- Anyone can be able to do this type of welding because it requires fewer skills.
- Chances of having a porous weld are quite low if it is done in a detailed and accurate way.
- This welding can also be done on contaminated materials.
- It doesn’t require any heavy equipment hence it is quite convenient and easy.
- Last but not the least, it has higher deposition rates than other welding methods. As it can be used on contaminated surfaces as well, less cleaning is required. It can also save time. Besides, the good quality weld can be guaranteed because of its high deposition rate.
Disadvantages of FCAW welding
Of course, it has some disadvantages as well. As compared to other types of welding, you might not find this method suitable in the following ways:
- Due to the continuous formation of smoke during welding, it becomes difficult to see the welding area and the weld itself.
- It produces more smoke if compared with other techniques.
- Weld can be porous if the gases are not able to escape from the weld metal before the metal weld becomes solid.
- The filler material can be expensive because of its tabular nature.
- Slag formation is counted as one of the main drawbacks. It should be properly removed to ensure a strong weld.
- It can also be health-hazard because the welder has t work with toxic fumes.
The electrode should be handled with great care. The filler material should be selected carefully according to the nature of the metal you are going to weld. It is only suitable for welding heavy and thicker metals. Hence this method is not advised to be used on thin metals.
FCAW welding has wide use in different areas of life. You will mostly find it in the areas of heavy metal development. A few of its applications are listed below:
- It is widely used in construction and mechanical industries for welding purposes.
- The shipbuilding industry uses FCAW welding.
- It is also used for facing and surfacing.
- It has a wide range of use in the aerospace and automotive industry.
- Nowadays, it is frequently used to make artwork.
Metals suitable for FCAW welding
The FCAW welding process is popular for its versatile and flexible nature. Here is the list of some metals which are found to be compatible with this welding:
- Stainless steel
- Cast iron
- Low-alloy steels
- Carbon steel
- High-nickel alloys
Aluminum cannot be welded using this method. It is a non-ferrous metal and FCAW welding is not suitable for such metals.
FAQs
Is FCAW welding the same as MAG welding?
It is very similar to MAG welding. Almost similar equipment is used for both processes and fire feeds used for the two processes are also the same. The power supply is also the same for both weldings. Both of them are semi-automatic welding methods and have a high rate of production.
What is the use of FCAW welding?
It is used to weld heavy and thick metals. It also provides all-direction welding and is easy to handle. Hence it has a wide range of use in different areas such as construction sites, ship-building, and other manufacturing areas such as automobiles, etc.
Is FCAW welding strong?
This type of welding has a high deposition rate. That is why it can be done indoors and can also be used outdoors conveniently. It is independent of the weather conditions. Most important thing is to choose the right filler material. The right filler material can ensure a strong weld with clean finishing.
Why carbon dioxide and argon is used in FCAW welding?
A mixture of argon and carbon dioxide is very efficient when it comes to welding metals using the FCAW method. Weld penetration can be enhanced using this method. It also results in increased bead wetting.
Wrapping up
No doubt all welding techniques are very helpful. Not all of them are easy to learn but one can gain experience through practice. You can work with the one you find easy for you.
However, sometimes we have to use a certain technique for certain metals. It’s mainly because some metals have different properties than others. And it is also one of the quickest and simplest ways to guarantee a good quality weld.
Everything that you need to know about FCAW welding is mentioned above in detail. So if you are dealing with heavy and thick metals at your workplace, you might want to use the FCAW method for welding.
Besides all this, be careful because your safety is the priority. With proper safety measures, not only you can get a better result, but also you can prevent yourself from any harm.