A 1% decrease in O2 purity results in what percent reduction in cutting efficiency?

A 1% decrease in O2 purity results in what percent reduction in cutting efficiency?

• A. 5%
• B. 10%
• C. 25%
• D. 50%

Answer: (C)

Oxygen purity has a strong influence on cutting speed because the oxidation reaction at the cut front is what drives the heat and material removal. When the oxidizer supply is reduced, there’s less oxygen available to sustain the exothermic reaction, so flame temperature and the rate of oxidation drop. This makes the cutting process slower, and in practice this relationship isn’t perfectly linear—the system responds more strongly to small purity changes due to how the reaction rate and heat transfer interplay with the torch. In this context, a 1% decrease in O2 purity is observed to reduce cutting efficiency by about 25%, which is why that choice is considered correct: it reflects the disproportionately large impact a small purity loss can have on cutting speed. The other options would imply a smaller or much larger change than what’s typically observed for a minor purity drop, which doesn’t align with how sensitive the cutting process is to oxidizer quality.

Oxygen purity has a strong influence on cutting speed because the oxidation reaction at the cut front is what drives the heat and material removal. When the oxidizer supply is reduced, there’s less oxygen available to sustain the exothermic reaction, so flame temperature and the rate of oxidation drop. This makes the cutting process slower, and in practice this relationship isn’t perfectly linear—the system responds more strongly to small purity changes due to how the reaction rate and heat transfer interplay with the torch. In this context, a 1% decrease in O2 purity is observed to reduce cutting efficiency by about 25%, which is why that choice is considered correct: it reflects the disproportionately large impact a small purity loss can have on cutting speed. The other options would imply a smaller or much larger change than what’s typically observed for a minor purity drop, which doesn’t align with how sensitive the cutting process is to oxidizer quality.