745 Welding, Cutting, and Brazing Safety

Arc Welding/Cutting Equipment

Gas Tungsten Arc Welding (GTAW / TIG)

Gas tungsten arc welding provides precise control over weld quality by using a non-consumable tungsten electrode to produce the weld, frequently used on thin materials and for high-quality welds.

Equipment includes: DC or AC/DC power source, TIG torch, tungsten electrode, shielding gas, filler rods, foot pedal, helmet, and PPE.

Safe Operation Guidelines: The following is a brief list of steps to safely operate the equipment:

1. Inspect Equipment
   • Check power supply, torch, cables, foot pedal, shielding gas cylinder, regulator, and hoses for damage or leaks.
   • Ensure proper tungsten type and size is installed and correctly prepared (sharpened or balled, depending on material).
2. Set Up Shielding Gas
   • Open shielding gas cylinder slowly (usually argon or argon mix).
   • Adjust regulator to proper flow rate (typically 15–20 CFH).
3. Prepare Workpiece
   • Clean the joint area to remove oil, grease, dirt, or oxides.
   • Clamp or secure the workpiece to ensure a good ground connection.
4. Adjust Welding Machine
   • Select correct polarity (DCEN for steel, stainless; AC for aluminum).
   • Set amperage based on material type and thickness.
5. Start Welding
   • Position torch at correct angle (typically 10–15 degrees off vertical).
   • Start arc using foot pedal, lift arc, or high-frequency start.
   • Feed filler rod manually as needed, while maintaining proper arc length.
6. Shut Down
   • Allow post-flow of shielding gas to protect cooling weld and tungsten.
   • Turn off power supply and close shielding gas cylinder valve.
   • Depress pedal or trigger to bleed off remaining gas pressure, then turn off regulator.

Safe Operation Guidelines: The following safe procedures and practices help prevent welding injuries and illnesses:

• Ensure torch assembly is correctly configured (collet, tungsten, ceramic cup). A properly assembled torch prevents gas leaks and maintains a stable arc. Workers must double-check that the collet grips the tungsten tightly, and the ceramic cup is the right size for good gas coverage.
• Select correct shielding gas (argon, helium mixtures) and flow rates. Using the right gas protects the weld from contamination. Argon or argon-helium mixtures are common for TIG welding. Setting the correct flow rate ensures a smooth weld and prevents oxidation or porosity.

• Adjust welding currents carefully and use remote amperage controls. Setting the correct current helps control heat input and prevents burning through the metal. Remote controls let the welder adjust amperage while working, which improves precision and safety.
• Protect eyes and skin thoroughly due to intense UV radiation from TIG. TIG welding produces strong ultraviolet light that can burn eyes and skin. Welders must wear proper PPE, including a welding helmet with the correct shade, gloves, and flame-resistant clothing.
• Regularly sharpen tungsten electrodes properly to maintain arc stability. A sharp, clean tungsten electrode creates a stable and focused arc. Dull or dirty electrodes can lead to poor weld quality and increase the chance of arc wandering or contamination.
• Turn off shielding gas and power source when not welding. To prevent gas waste, fire hazards, and electrical risks, welders must shut off the gas flow and power supply when they finish welding or take breaks.

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