10 Different Type’s Special Welding Process

Do you want to learn about the different types of special welding processes? There are a lot of variations depending on what type of project it is. For example, if you need to weld metal pipes together, then you will use one process. If you need to weld two pieces of metal furniture together, then another process may be used. In this guide, we cover all the different types of welding processes and how they work.

types of special welding process

Welding is one of the most important manufacturing processes in the world. With it, you can join metals together to create a sturdy bond that is strong enough for even some heavy-duty applications (such as cars and bridges). Types of welding techniques – or more accurately, types of special welding processes – are so numerous because each one has its own advantages and disadvantages depending on what they're being used for.

The following list goes over some different types of these specialized methods: 

01. Electron Beam Welding-EBW
02. Electro Slag Welding-ESW
03. Flow Welding-FW
04. Induction Welding-IW
05. Laser Beam Welding-LBW
06. Laser-Hybrid Welding-LHW
07. Percussion Welding-PEW
08. Thermite Welding-TW
09. Electro Gas Welding-EGW
10. Stud Arc Welding-SAW

01. Electron Beam Welding-EBW

Electron beam welding is a procedure that uses high technology and is very precise. This type of welding uses high-velocity electron beams which join pieces of metal when shot. Due to the high heat produced by moving electrons, the separate parts of metal melt and join together tightly. To make sure that heat does not dissipate, the process occurs in an airless vacuum. The vacuum also helps to minimize heat around the welder`s working space.

Electron beam welding is ideal for almost all types of metals, from making aerospace components, saw blades, nuclear devices and even in medical services. EBW is an automated welding method meaning hence little energy is needed to operate. It also keeps your working environment clean and heat friendly because the whole process takes place in a vacuum.

02. Electro Slag Welding-ESW

This process melts the metal pieces to be joined and the filler metal using a molten slag. As the welding process is on, a full cross-section is made by the moving slag hence shielding the welding pool. This process begins by initiating the arc. Then, granulated flux is heated by the arc to form slug. When enough slag is created, the arc is extinguished. The resistance of the produced slag keeps it molten as current flows between the metal pieces and the electrode.

This welding method is capable of welding thick metals in a single pass because the rate of deposition is high. Electro slag welding reduces the overall welding cost because joint preparation is minimal hence lowering the expenses of material handling. The process also has low embrittlement of hydrogen, and the transverse shrinkage is little.

03. Flow Welding-FW

Flow welding involves the production of coalescence through heating the molten filler metal. The coalescence is then poured over the welding joints to be joined until the required weld heat is achieved and the needed filling material is added. Flow welding process minimizes distortion and works best in situ, especially when joining rails.

04. Induction Welding-IW

Induction welding involves the use of electromagnetic induction principles to produce heat through metal objects. When metals that conduct heat are electrically heated molecules of the metals, start resisting leading to the production of very high heat. The resultant heat causes the metallic object to melt thus fusing with any other metal.

The induction welding process produces heat electromagnetically in any metal that conducts heat, leading to a resistance of the metal molecules. When compared to other welding processes, induction welding reduces time cycle, consumption is low, and it has uniform heating. Induction is efficient and reliable because it utilizes energy effectively. Induction welding method can be applied in forging, tampering, soldering, metal bonding and hardening any metallic surface.

05. Laser Beam Welding-LBW

Laser beam welding involves the transfer of a very high-density heat which is applied from a distance to the metal materials being welded. This method bounds metals together at high temperatures and metals cool down quickly soon after the laser beam is withdrawn. The high heat from the beam guarantees a strong bond and metals do not form cracks because of the quick cooling. Usually, the size of the beam can range between 0.2 millimeters to 13 millimeters, but for welding, only smaller sizes are applied.

Depending on the application, a continuous laser beam or a pulse is applied. On thin welding materials such as sheets, pulses are appropriate, while a continuous laser beam is suitable when producing deep welds. Due to the concentrated heat source, the laser beams produce narrow, deep welds. Laser beam welding is widely applied in automotive industry fast and high volume production.

06. Laser-Hybrid Welding-LHW

Laser-hybrid technology involves combining a laser with other welding processes that are compatible. Some of the methods that can be combined with laser include plasma welding, TIG(Tungsten Inert Gas), MIG (Metal Inert Gas) and Metal Active Gas (MAG).

In the building of ships, for instance, large and thick plates made of steel are welded together, but because these plates are massive, they leave big gaps which cannot be bridged by laser beams. Therefore, this setback is solved by metal active gas (MAG) with laser welding. Laser welding is fast and produces the high-density heat required to make deep welds while on the other hand, the metal active gas torch fills the gap between plates using the filling wire.

Laser-hybrid technology is faster and effective than when welding using MIG or laser technique alone and the welding materials are less distorted. This technology has gained popularity and is widely used in making trucks, creating cranes and in automobile and rail producing industries.

07. Percussion Welding-PEW

Percussion welding is a type of resistance welding that involves welding together two different metal pieces using an arc of high-intensity heat followed immediately by pressure application which binds the two metal pieces together. By use of collision, the two molten metal pieces are then pressed together until some of the molten metal flow out of the joint.

Percussion welding is applied best when welding metal pieces of similar cross-section and geometry. PEW is a speedy process, and it causes minimal damage to the surface that is close to the welds. Heat is also balanced appropriately because it is only focused on the endings of the metal pieces to be joined.

This welding method is applied when welding fine wires, for example in terminals and lamps it is used to weld fine wires to filaments. It is also involved in butt joints to fix rods and cables.

08. Thermite Welding-TW

Thermite welding is an exothermic reaction that involves using extremely high temperatures to heat a metal between an aluminum and a metal oxide or between any other reducing agent. Filler metal is produced from the melted metal pieces. TW can involve or not involve pressure. This welding process is a bit slow when compared to other welding processes because it can take up to 30 seconds. It takes the same time despite the number of chemicals involved in the process.

This welding process is used to bind rails together in railroad construction. The only advantage with this process is that its heat is created through a chemical reaction; hence it does not need any power source from outside. Parts that are heavy and large can be comfortably joined using this process.

09. Electro Gas Welding-EGW

EGW or electro gas welding is an arc welding process that is vertically positioned. This process is used for welding vertically positioned sections, and the sections are placed edge to edge in one pass. For this process to operate, it needs special equipment; hence it is called machine welding process. Between the two metal pieces to be joined there is a cavity into which the weld metal is deposited. The space between the cavity has two copper dams which are water-cooled that prevent slag from overflowing.

Electro gas welding method is widely applied in the building of, large diameter pipes, ships, bridge construction and building thick walls and large diameter pipes.

10. Stud Arc Welding-SAW

Stud arc welding involves using the stud as an electrode to join stud to a flat plate. Depending on the type of metal piece being welded, different polarity is applied. For instance, there are metals like steel which need DCEN ( direct current electrode negative while others like aluminum demand DCEP or direct current electrode positive.

For the process to form a weld, arcs that have a flange usually are used. The arcs should also have some small nubs. To create the required weld, an unthreaded, necked downside of the welding nuts is used. This process also uses a ferrule that helps in concentrating the heat produced; hence it prevents oxidation and retains the molten metal at the right weld area.

Arc stud welding is mainly used in fields that require high quality because it is a one-sided weld process; thus, the reverse side is kept clean and attractive since it is not marred.

Final Verdict

When it comes to welding, there is a wide variety of different techniques and technologies that can be used. It’s important for welders to know the pros and cons of each in order to make the best decision about what kind of process they should use. In this blog post we explored 10 common types of welding processes-EBW, ESW, FW, IW, LHW and TW-and highlighted their strengths as well as some weaknesses so you don't have any surprises when working with these methods in your business.