Question

what is the primary function of oxygen in oxyfuel cutting (ofc)?
a it melts the metal to make joining easier.
b it reacts with metal to produce high - temperature combustion.
c it prevents slag from forming on the metal surface.
d it acts as a shielding gas to protect the molten metal.

Explanation:

In oxyfuel cutting, oxygen's main role is to react with the metal (usually iron - based metals) to cause combustion at high temperatures. This combustion helps in cutting the metal. Option A is incorrect as OFC is for cutting, not joining, and oxygen doesn't primarily melt the metal for joining. Option C is wrong because oxygen doesn't prevent slag formation; in fact, the reaction can produce slag - like by - products. Option D is incorrect as shielding gases in welding (different from OFC's main oxygen role) are like argon, not oxygen, which is a reactive gas here.

Answer:

B. It reacts with metal to produce high - temperature combustion.