The welding process is an inextricable part of the metal fabrication industry. Different welding techniques are utilized to produce the best quality and reliable products.
Since a product’s reliability depends upon the suitability and quality of the welding technique, it is critical to understand different welding techniques.
Without knowing the potential, suitability for different applications, advantages, and disadvantages of a particular welding technique, we can’t get the best out of it.
Seam welding is a modern welding technique used in high-profile welding processes. Unlike stitch welding, which is an intermittent process, it is a continuous welding process.
If you are curious to know What Seam Weld is? Give a read to this article. I’ve discussed the seam welding process, its properties, applications, and pros and cons.
How Does Seam Weld Works?
Seam welding joins the pieces of similar or dissimilar materials in a continuous seam. It is a widely used welding technique for both flat and corner welds.
Seam welds feature higher strength than any other welding technique since they are present throughout the length of a joint. A uniformly welded region created through seam welding in fusion binding is sometimes even stronger than the joined materials.
Since the high strength is the key property of seam weld, it is mainly employed in the process where the strength of the joint is a paramount concern.
Additionally, seam weld is a controlled technique in which a very low heat input is utilized to the under-process materials. The low input of heat minimizes the damage and helps maintain the original properties of materials.
Therefore it is used in thin and delicate welding projects as well. Depending upon the method of heat generation seam world is further divided into two main categories, Resistance Seam Weld and Friction Seam Weld.
Resistance Seam Weld
Resistance seam weld is a technique in which two copper electrodes work on the principle of metal resistance. When current is passed through the electrodes, an immense amount of heat is generated due to resistance between metallic electrodes.
The resistance seam welding is almost similar to continuous spot welding. The major difference between the two is the type of electrode. In resistance seam welding, roller electrodes are used, while static electrodes are used in continuous spot welding.
In resistance seam welding, the metal sheets being welded are held between the shape electrodes, and current is passed through them; the high heat production begins to melt the metal sheets held by rollers, resulting in a strong joint between them. The resistance seam welding could be either continuous or intermittent.
In intermittent roller motion, the speed of the roller is not fixed. However, in continuous resistance welding, we have a predetermined roller speed that is kept constant throughout the process.
The average speed of continuous seam welding is around 60-inches/ minute, but it varies depending upon the thickness of the material, heat input, and sensitivity of the project.
Applications of Resistance Seam Weld
Seam weld has multiple applications in metal fabrication projects. Here are some of the common applications of this high-strength welding technique.
Seam weld is used for welding different metal alloys like magnesium alloys, nickel alloys, and stainless steel work-pieces.
Since seam weld is known for its high strength and reliability, it is used in the fabrication of vehicles and aircraft fuel tanks. It is also used to make steel tanks and fuel cans since the risk of leakage is almost zero.
Refrigerators and Transformers
Metal fabrication during the manufacturing of refrigerators and transformers is a sensitive process. Seam weld is used to complete these sensitive welding projects.
Resistance seam welding is used in the manufacturing of exhaust systems. Seam welding is a reliable and high-strength process and comes with its own advantages and drawbacks.
Resistance Seam Welding Advantages
Fluid-tight and Airtight Seals
Seam weld produces airtight and fluid-tight seals, making this process highly useful for creating metallic structures that require gas, water, or liquid leakage protection.
If you are concerned with the joint overlapping, choose seam welding. There are fewer chances of overlap production; if it is produced, it won’t be thicker than 10mm.
Seam welding is a simple and straightforward process, unlike plasma and arc welding. It is easy to learn, and even those not skilled can do the job. Since it’s a fully automated process, there are fewer chances of human error.
Seam welding is a fully automated process with the automatic transfer, loading, and unloading of materials. Since the metal does not include manual input or output, it’s faster than any other welding technique.
The current is passed intermittently through the electrodes, and the heat produced is fully utilized in the welding process. The minimum heat dissipation and maximum current utilization make the process cost-effective, time-saving, and environmentally friendly.
The automated setup makes the process highly repeatable. Therefore, this technique is utilized in big metal fabrication projects to increase production and achieve big targets within a limited time span.
Due to maximum labour input and faster processing, this is one of the most cost-effective welding techniques. The process saves much money regarding labour cost, time, and component transfer. It reduces the cost to about half of the original process.
The filtration material produces the major pollution associated with the welding process. Thankfully, no filtration material is used in seam weldings, and therefore, no solid waste is produced in this process. Since the process doesn’t produce any gas or fumes, its contribution to air pollution is almost zero.
Resistance Seam Welding Disadvantages
The thickness of metal sheets is the major concern of seam welding. It becomes difficult to handle the seam welds if the thickness of metal sheets is above 3mm.
Curved Welds Limitations
Resistance seam welding uses rollers to produce high-strength uniform welds along straight lines. However, when it comes to complex and curved welds, the process cannot handle them perfectly. This is one of the major limitations of this process.
Friction Seam Weld
In friction seam, weld materials are joined together in a solid phase. Neither of the material is melted in friction seam weld. This method uses friction to generate heat instead of electrodes. This welding technique uses a rotating consumable bar with U or V shape groove. Also, have a look at how to join steel pipes without welding.
The material to be joined is pressed underneath the rotating consumable bar, and heat is generated through the friction process. No fusion of interfusion takes place during this process.
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