Welding Terms

Welding: Joining together pieces of metal by heating surfaces to a melting point.

Welding Rod: A filler metal and should be mild steel. Also known as an electrode.


Acetylene: The primary fuel for oxy-fuel welding and is the fuel of choice for repair work and General cutting and welding.

Oxygen: This is not the fuel.  Oxygen chemically combines with the fuel to produce the heat for Welding.

MAPP Gas: Liquified petroleum gas mixed with methylacetylene-propadiene gas.  This has a heat value less than acetylene and can be shipped in small containers.

Nitrogen: This is used as “Purge” gas and as an assistant gas for laser cutting.  It also enhances plasma cutting and in welding stainless steel.

Argon: This is used for welding in Mig and Tig applications. It also acts as an insulating layer in welding.

Unimix 75/25 Gas:  (75% argon & 25% carbon dioxide) Common mix used for short circuit gas metal arc welding.   (Mig = Metal Inert Gas.)

Mig: This is a simple and easy process to learn that uses continuous feed wire.

Tig: This process uses welding rods slowly fed in the weld puddle and used on thinner materials.  (Tig = Tungsten Inert Gas.)