Oxy-Acetylene Flame — Location of Maximum Temperature In a neutral oxy-acetylene flame used for welding, where does the maximum flame temperature occur relative to the visible flame zones?

Introduction / Context:
A neutral oxy-acetylene flame exhibits two distinct luminous zones: an inner cone (primary combustion) and an outer envelope (secondary combustion). Knowing where the peak temperature lies helps a welder position the flame for efficient heating and fusion.

Given Data / Assumptions:

• Neutral flame with approximately equal oxygen and acetylene flow for welding steel.
• Standard welding tip and normal gas pressures.
• Observation of visible inner cone and outer envelope.

Concept / Approach:
The primary combustion zone (inner cone) attains very high temperatures due to intense, near-stoichiometric combustion. Practical welding guidance places the work near the tip of the inner cone to capitalize on the maximum heat, achieving rapid melting with minimal oxidation when properly adjusted.

Step-by-Step Solution:
Identify flame zones: inner cone (primary) and outer envelope (secondary).Associate maximum temperature with the intense primary combustion region.Therefore, select “at the inner cone”.

Verification / Alternative check:
Standard welding texts instruct holding the inner cone close to the work for maximum heating efficiency.

Why Other Options Are Wrong:
Outer cone: cooler than the primary zone.Between cones: heat exists, but peak guidance is referenced to the inner cone tip.Torch tip/nozzle interior: not a combustion zone and not at peak temperature.

Common Pitfalls:
Confusing the exact peak location as slightly beyond the inner cone; in practice welders target the inner cone region for maximum heat.

Final Answer:
at the inner cone