Types Of Welding – Classification of welding processes

Welding is a process of permanently joining two or more parts by the application of heat and (or) pressure. As per American Welding Society 50 different welding processes available today; some are very popular among the industries such as SMAW, GMAW, GTAW, SAW, FCAW etc. whereas some are very specific and limited to few industries such as USW, RSW, DW etc.

Welding processes are broadly classified as fusion welding and solid state welding;

FUSION WELDING: In Fusion welding coalescence is done by melting the base metals by the application of heat. Required heat is generated by an electric arc formed between the electrode and the workpiece. Very often filler metal is also used. Commonly used fusion welding processes are:

1. Arc Welding

• SMAW (Shielded Metal Arc Welding or stick Welding)
• GMAW (Gas Metal Arc Welding or MIG welding)
• GTAW (Gas Tungsten Arc Welding or TIG Welding)
• SAW (Submerged Arc Welding)
• FCAW (Flux Cored ARC Welding)
• PAW (Plasma Arc Welding)
• Carbon Arc Welding 
• Stud Welding

2. Resistance Welding

• Resistance Spot Welding
• Resistance Seam Welding
• Resistance Projection Welding
• Flash Welding

3. Oxyfuel welding

4. Others

• Electron beam welding
• Laser beam Welding

SOLID STATE WELDING: In solid state welding, joining is done by the application of pressure alone or a combination of pressure and heat. Normally the base metal is not reached to the melting point, if heat is applied to obtain the coalescence and filler metal is not used. Some of the solid state welding processes are:

1. Diffusion welding (DFW)
2. Friction welding (FRW)
3. Ultrasonic welding (USW)
4. Cold Welding
5. Forge welding
6. Explosion welding (EXW)

In the following video, I have simplified the different welding processes and categorized for your easy understanding. Please watch this video and share your views as well as queries. I will be glad to answer your queries.