During an oxy-fuel cutting operation on a 25 mm thick steel plate, the technician notices excessive slag adhesion and a wide, rough kerf. Which of the following adjustments would most likely improve the cut quality?

Question: During an oxy-fuel cutting operation on a 25 mm thick steel plate, the technician notices excessive slag adhesion and a wide, rough kerf. Which of the following adjustments would most likely improve the cut quality?

Answer options:

• Increase cutting oxygen pressure and decrease cutting speed.
• Decrease cutting oxygen pressure and increase cutting speed.
• Increase both preheat flame intensity and cutting speed. ✅ Adjust cutting oxygen pressure and speed; typically, excessive slag and rough kerf indicate insufficient oxygen pressure or incorrect speed (too fast or too slow).

Correct answer: Adjust cutting oxygen pressure and speed; typically, excessive slag and rough kerf indicate insufficient oxygen pressure or incorrect speed (too fast or too slow).

Explanation: Excessive slag and a rough/wide kerf are common indicators of incorrect cutting oxygen pressure or cutting speed. Adjusting these parameters, often increasing oxygen pressure slightly or optimizing cutting speed, is necessary for a clean, narrow kerf. Too little oxygen or too low speed can lead to poor penetration and slag, while too high speed can cause the flame to not penetrate fully.