Sheet metal welding processing involves either welding multiple parts together to achieve the processing objective or welding the edges of individual parts to increase their strength.

MIG Welding (Metal Inert Gas):

1. MIG welding uses a continuous wire electrode that is fed through a welding gun, along with a shielding gas to protect the weld pool from atmospheric contamination.

1. TIG Welding (Tungsten Inert Gas):

2. TIG welding utilizes a non-consumable tungsten electrode and a separate filler material, if needed, along with a shielding gas.

1. Spot Welding:

2. Spot welding involves the application of electric current to create localized heat and pressure, melting and fusing the metal at specific points.

1. Arc Welding:

2. Arc welding uses an electric arc between an electrode and the workpiece, creating the heat needed for fusion. It can be manual (SMAW) or automated (SAW).

1. Seam Welding:

2. Seam welding is a continuous welding process where a wheel electrode rolls along the joint, creating a series of overlapping spot welds.

Sheet metal welding requires careful consideration of factors such as material type, thickness, joint design, and intended use of the final product. 

The choice of welding method depends on the specific requirements of the application and the desired characteristics of the welded joint.