Oxy-fuel welding and cutting process results in oxides that mix with the molten iron.

5720 F ref. Victor Equipment Co. booklet OXY-FUEL Welding ,Cutting , and Heating Guide c.1996

turn it on and start cutting

Oxygen is used in welding to increase the burn rate of the fuel gas, such as acetylene, in the oxy-fuel welding process. The oxygen reacts with the fuel gas, creating a high-temperature flame that is used to melt and join metal together. Additionally, oxygen is used in oxy-fuel cutting to aid in the combustion process, resulting in a clean cut through metal.

Evan A. Atkins has written:

'Electric arc and oxy-acetylene welding' -- subject(s): Electric welding, Oxyacetylene welding and cutting, Welding