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Tig Welding(tungsten inert gas)(tungsten inert gas)
By Mr. Berner
04/04/08
Objectives
• You will be able to describe the process of TigWelding and the benefits of it’s use
• You will know how to set up and prepare a Miller Tig WelderMiller Tig Welder
• You will understand polarity and how to produce a desired weld
• You will be able to safely weld Butt, Lap, T and Corner Joints
Key Terms
• Air‐cooled Torch• Amperage• Collet• Collet Body
• Inert Gas• Non‐consumable electrode
• NozzelCollet Body• End Cap• Foot Pedal• Gas Lens• GTAW
• Polarity• Post Flow• Tig
What is Tig Welding?Tig Welding (tungsten inert gas) uses• a tungsten electrode that heats the metal you are welding
• an argon gas which protects the weld pool from airborne contaminants
• a filler metal, when required is added by hand
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Why use Tig Welding?
• Weld more metals than any other process
• Create high quality, clean welds– No sparks or spatter
– No flux or slag
– No smoke or fumes
• Use one shielding gas for all applications
• Weld in all positions
Disadvantages
• Slower travel speeds
• Lower filler metal deposit rate
• Requires more hand eye coordination
• Brighter UV rays
• Equipment costs can be higher
Remember Personal Safety
1) Wear safety glasses2) Wear an approved shaded welding helmet3) Wear insulated gloves4) Wear durable clothes without pockets and4) Wear durable clothes without pockets and
folds5) Wear shoes or boots that will provide
protection to your feet
How do I set up the Tig Welder?
1. Connect Torch
2. Connect Gas Hose and Regulator to Argon Cylinder
3 C A d l3. Connect Amperage Foot Pedal
4. Connect Work Clamp to the Work Piece
5. Prepare the Tungsten
6. Assemble the Torch
7. Install the Tungsten
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Before I Tig Weld
1. The tungsten should never touch the work piece, or it will be contaminated
2. The tungsten tip should be ground down to keep arc from wanderingp g
3. The argon flow pressure should be set to 30 psi
4. Choose the correct polarity for the application
5. Always push the torch toward the filler metal
Choosing Polarity
Choosing Gas Flow Rate Choosing Current Range
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How do I Tig Weld?
1. Align your torch at the correct angle
2. Set the foot pedal to the correct amperage, so that you create a ¼” wide weld pool
3 Align your filler metal to the correct angle3. Align your filler metal to the correct angle
4. Heat an area of the joint’s surface
5. Dab the filler metal quickly
6. Push the torch forward enough to heat a new weld pool and cool the previous weld pool
Butt Welds
Lap Joint Welds T Joint Welds
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Corner Joint Welds