What is a common sign that indicates a flame is not properly adjusted?

A common sign indicating that a flame is not properly adjusted is the production of excessive soot. When the flame is not tuned correctly, particularly in oxyfuel cutting, the combustion process is incomplete. This inefficiency occurs when there is an imbalance in the oxygen and fuel mixture, typically resulting in a fuel-rich flame. In such cases, carbon particles formed during combustion can accumulate, leading to a sooty appearance. This not only suggests that the flame is inefficient but can also impair the cutting process by affecting the quality of the cut and creating fallout that could damage the work area. Properly adjusted flames should burn cleanly and produce minimal to no soot, reflecting a well-balanced mixture of oxygen and fuel that facilitates effective and efficient cutting.

In contrast, a small and contained flame generally indicates a well-controlled and safe operation, while a stable blue flame indicates proper combustion with the correct oxygen-to-fuel ratio. A yellow and flickering flame, on the other hand, is still a sign of improper adjustment but is not as definitive an indicator of soot production as excessive soot itself.