Question

Oxygen to acetylene ratio in carburising flame is

• A. 0.9:1
• B. 1:2
• C. 2:1
• D. 1:2.5

Hint:

Carburising (Reducing): $O_{2} < C_{2}H_{2}$. Neutral: $O_{2} = C_{2}H_{2}$. Oxidising: $O_{2} > C_{2}H_{2}$.

Answer 1

The Correct Option is A

Step 1: Concept In oxy-acetylene welding, the characteristics of the flame depend on the volume ratio of the two gases.

Step 2: Meaning A neutral flame has a 1:1 ratio. A carburizing flame has an excess of acetylene, which provides a reducing atmosphere.

Step 3: Analysis Because there is more acetylene than oxygen, the ratio of Oxygen to Acetylene must be less than 1.

Step 4: Conclusion Among the options, 0.9:1 represents an acetylene-rich mixture, which is the definition of a carburising flame. Final Answer: (A)