TIG welding, also known as Gas Tungsten Arc Welding (GTAW), is a precise and versatile welding process commonly used to join metals such as stainless steel, aluminum, and copper. TIG welding utilizes a non-consumable tungsten electrode, a shielding gas, and a filler metal (if needed). Here's an overview of the TIG welding process:
Select the appropriate TIG welding machine for the job, considering factors such as power output, AC/DC capability, and control features.
Connect the welding machine to a suitable power source.
Install a high-quality tungsten electrode (usually thoriated, lanthanated, or ceriated) into the TIG welding torch.
Choose the appropriate shielding gas based on the metal being welded.
Common shielding gases for TIG welding include pure argon for non-ferrous metals and a mixture of argon and helium for ferrous metals.
Prepare the workpiece:
Ensure the metal surfaces to be welded are clean, free of rust, paint, and contaminants.
Clamp or secure the workpiece in a stable position to prevent movement during welding.
Adjust welding settings:
Set the appropriate amperage, voltage, and balance control (if using AC) on the welding machine based on the thickness and type of metal.
Consult welding procedure specifications (WPS) or manufacturer recommendations for initial settings.
Positioning and technique:
Hold the TIG welding torch with a proper grip and maintain a steady hand.
Position the tungsten electrode at a slight angle (typically 10-20 degrees) and maintain a consistent distance between the tip of the electrode and the workpiece (typically 1/8 to 1/4 inch or 3-6 mm).
Use a foot pedal or control switch to regulate the amperage and control the heat input.
Initiate the arc by striking the tungsten electrode against the workpiece and gradually withdrawing it to establish a stable arc.
Control the movement of the torch and the filler metal (if used) to create a precise weld pool and control the heat input.
Dip the filler metal into the molten pool as needed to add material and strengthen the weld joint.
Maintain a consistent rhythm and speed, moving the torch along the joint in the desired direction.
Gradually reduce the amperage and allow the weld to cool naturally, avoiding rapid cooling methods that may lead to distortion or cracking.
Inspect the weld for proper fusion, penetration, and quality. Clean any discoloration or debris from the weld if necessary.
Remember to follow safety precautions while TIG welding, such as wearing appropriate protective clothing, gloves, and a welding helmet with a proper shade for eye protection. Ensure proper ventilation in the workspace to prevent the buildup of hazardous fumes.