Welding Torch — What It Is and Why It Matters
A welding torch is the handheld device that delivers the welding arc, shielding gas, and (in MIG/flux-core) the filler wire to the workpiece. In TIG welding, the torch holds the tungsten electrode, directs shielding gas through a ceramic cup, and may include water cooling for high-amperage work.
MIG guns (also called MIG torches) feed wire through a contact tip inside a nozzle that directs shielding gas. They are rated by amperage and duty cycle and are available in air-cooled (lighter, simpler) and water-cooled (for sustained high-amperage production) configurations.
TIG torches come in numerous sizes — from small No. 9 air-cooled torches for light work to large No. 20 water-cooled torches for heavy industrial welding. The torch body, back cap, collet, collet body, ceramic cup, and gas lens (if used) are all serviceable components that affect arc quality and gas coverage.
Frequently Asked Questions
How do I choose the right TIG torch size?
Match torch amperage rating to your typical welding range. A No. 17 air-cooled torch handles up to about 150 amps. A No. 26 air-cooled handles up to 200 amps. For sustained welding above 200 amps, a water-cooled torch (No. 20 or No. 18) prevents overheating and hand fatigue.
When should I replace my MIG gun?
Replace the contact tip when you notice erratic arc behavior, the nozzle when spatter buildup restricts gas flow even after cleaning, and the liner when you experience inconsistent wire feed despite proper tension. Most MIG gun consumables are inexpensive and should be treated as routine maintenance items.