Gas nozzle at the end of a GTAW torch, made of alumina ceramic or heat-resistant glass and sized in sixteenths of an inch of bore, so a number 8 cup is 1/2 inch. Bigger cups, often paired with a gas lens, give broader coverage for stainless and titanium. Pipe welders rock the cup on the bevel in walking the cup. On MIG guns the copper nozzle is also called a cup and must be kept clear of spatter.
Throw a number 12 cup with a gas lens on there, it's titanium, I want the whole puddle covered.
Also heard as
- nozzle
- gas cup
- TIG cup
Related terms
GTAW
Gas tungsten arc welding: an arc from a non-consumable tungsten electrode under inert gas, known as TIG.
Walking the cup
TIG pipe technique of rocking the ceramic cup along the bevel to move the torch in a steady weave.
Purge
Inert gas flowed inside a pipe or behind a joint to keep the back of the weld from oxidizing.
Sugaring
Heavy oxidation on the back of a stainless or titanium weld that leaves a rough, grainy crust like sugar.