Submerged arc welding is a flexible and more operator-friendly alternative to metal inert gas welding.
This procedure is a partially or fully automatic process. Most often, operators program a fabrication machine to execute a submerged weld automatically.
Submerged arc welding encompasses feeding a continuous arc through an electrode and the workpiece. During the procedure, a layer of powdered flux creates a protective gas shield. At the same time, the slag created by the process protects the work material.
The submerged arc welding process is highly versatile. For example, operators can adjust the welding arc voltage, current, electrode positioning, and speed. The ability to adapt these parameters enables operators to achieve ideal results.
To learn more about the process and technology behind submerged arc welding, read on.
Submerged Arc Welding Explained
During submerged arc welding, the welding arc travels under granular flux. As the electrode, or electrodes, passes over the material, submerged arc welding equipment enables operators to feed the weld region continuously.
Simultaneously, the operator can continually pour flux over the weld zone. Because the operator submerges the weld zone in flux, the fumes and gases created by the art do not enter the atmosphere. Operators may use lime, silica, magnesium oxide, calcium fluoride, or other materials for flux compound.
Benefits of Submerged Arc Welding
When the flux melts, it becomes conductive. This conductivity creates a current between the workpiece and electrode.
As this happens, a solid layer of flux completely envelops the melted metal. This coating shields the operator from sparking and prevents the generation of ultraviolet radiation vapors.
Modern submerged arc welding equipment is complex. However, most units have common main parts, such as the:
- Electrode
- Electrode wire feed unit
- Flux
- Flux recovery unit
- Flux topper
- Welding head
Typically, operators feed supply filler and flux through the welding head.
There are several benefits to submerged arc welding. Primarily, the process has a high deposit rate.
Furthermore, it creates little smoke. Also, there’s no need to prepare the edges of the metal for the procedure.
You can perform submerged arc welding in an indoor or outdoor environment. Either way, the procedure is safer compared to other welding methods. The flux blanket created by the process shields the operator and the work area from sparks.
Challenges of Submerged Arc Welding
Submerged arc welding produces high-quality deliverables. However, there are some challenges involved in the process.
This procedure results in a high-quality bond. It’s fast, and it increases productivity.
Furthermore, it’s flexible. Operators can perform welds in different modes, such as automated, semi-automated, and mechanized. However, submerged arc welding is limited to flat or horizontal applications for plating and welded tubing.
Submerged arc welding can produce seams with fewer defects compared to other joining processes. However, operators must still manage potential submerged arc welding problems, such as:
- Cracking
- Incomplete fusion
- Porosity
- Slag inclusion
Usually, porosity isn’t a problem with submerged arc welding. However, it can occur during the procedure. Porosity typically happens on the bead surface or below the sound surface.
During a submerged arc welding procedure, contaminants in the joint can cause this problem. Porosity can also occur due to improper storage of the electrode, which leads to rust. Oil on the electrode can also cause issues with porosity.
Porosity may also arise because of contaminants in the flux. This problem can occur when shops recycle flux without screening it properly
An operator can also create porosity by setting the wrong parameters. For example, they may set the voltage or travel speed too high, creating cavities in the welded joint.
Inclusion is another problem that can arise with submerged arc welding. Like other methods, operators must take precautions to avoid this issue.
Typically, you’d find inclusions at the overlap of passes or near the bevel or groove faces of a joining. Accordingly, it’s important to take steps such as angling the welding had properly and making sure there’s no flag or oxide residue in the path of a pass.
Types of Submerged Arc Welding
Another great benefit of submerged arc welding is its deep penetration rate. Usually, an operator performs automatic submerged arc welding to move a flux hopper and torch across a welding stream. The operator can also automate the voltage and wire feeding processes to ensure precise control of the submerged arc welding process.
It is, however, possible to perform electric submerged arc welding manually. However, this practice is growing increasingly rare.
Furthermore, there are relatively few operators who have experience performing manual submerged arc welding. Among those who remain with this experience, most will soon retire.
There are different kinds of submerged arc welding fabricating equipment. Some work with flat plates.
Others perform girth welds across pipes. Yet another device, helical submerged arc welding equipment, enables operators to perform the procedure as the material turns while the electrode, or electrodes, remain still.
Despite recent advances in the field, operators are always looking for ways to increase productivity. The reasoning behind this desire is simple. The more a shop can produce, the more finished goods it can deliver.
Fortunately, shops don’t have to look far for advancements in the field. Techniques emerge continually that help shops increase operator productivity.
Learn More About Building and Fabrication Methods
Now you know more about submerged arc welding!
It’s always a good idea to stay on the lookout for new and better ways to work. You never know when you might find a process that could put your company light years ahead of the competition.
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