TIG Welding Introduction

Background What is TIG? Also referred to as GTAW Tungsten Inert Gas Also referred to as GTAW Gas Shielded Tungsten Welding In TIG welding, a tungsten electrode heats the metal you are welding and gas (most typically Argon) protects the weld from airborne contaminants

Background TIG welding uses a non-consumable tungsten Filler metal, when required, is added by hand Shielding gas protects the weld and tungsten

Advantages Welds more metals and metal alloys than any other process High quality and precision Pin point control Aesthetic weld beads No sparks or spatter No flux or slag No smoke or fumes

Disadvantages Lower filler metal deposition rates Good hand-eye coordination a required skill Brighter UV rays than other processes Slower travel speeds than other processes Equipment costs tend to be higher than other processes

Safety Electric shock can kill. Always wear dry insulating gloves Insulate yourself from work and ground Do not touch live electrical parts Keep all panels and covers securely in place Fumes and gases can be hazardous to your health. Keep your head out of the fumes Ventilate area, or use breathing device

Safety Welding can cause fire or explosion. Do not weld near flammable material Watch for fire; keep extinguisher nearby Do not locate unit over combustible surfaces Do not weld on closed containers Arc rays can burn eyes and skin; Noise can damage hearing. Wear welding helmet with correct shade of filter Wear correct eye, ear, and body protection

Safety Hot parts can cause injury. Allow cooling period before touching welded metal Wear protective gloves and clothing Magnetic fields from high currents can affect pacemaker operation. Flying metal can injure eyes. Welding, chipping, wire brushing, and grinding cause sparks and flying metal; wear approved safety glasses with side shields

Safety Welding current can damage electronic parts in vehicles. Disconnect both battery cables before welding on a vehicle Place work clamp as close to the weld as possible

Techniques for Basic Weld Joints Arc Starting with High Frequency Torch position on left shows recommended method of starting the arc with high frequency when the torch is held manually By resting gas cup on base metal there is little danger of touching the electrode to the work After arc is initiated, torch can be raised to proper welding angle *Figure copied from “TIG Handbook”

Techniques for Basic Weld Joints Manual Torch Movement ENBE 499 *Figure copied from “TIG Handbook”

TIG Shielding Gases Argon Helium Argon/Helium Mixtures

TIG Shielding Gases Helium Argon Good arc starting Good cleaning action Good arc stability Focused arc cone Lower arc voltages 10-30 CFH flow rates Helium Faster travel speeds Increased penetration Difficult arc starting Less cleaning action Less low amp stability Flared arc cone Higher arc voltages Higher flow rates (2x) Higher cost than argon

TIG Shielding Gases Argon/Helium Mixtures Improved travel speeds over pure argon Improved penetration over pure argon Cleaning properties closer to pure argon Improved arc starting over pure helium Improved arc stability over pure helium Arc cone shape more focused than pure helium Arc voltages between pure argon and pure helium Higher flow rates than pure argon Costs higher than pure argon