What indicates the presence of a carburizing flame during oxyfuel cutting?

The presence of a carburizing flame during oxyfuel cutting is indicated by a small, defined inner cone and excessive soot. In this type of flame, the acetylene gas is in excess relative to oxygen, which leads to a reduction in the amount of oxygen available for combustion. As a result, this incomplete combustion creates a softer flame that can deposit carbon on the metal being cut, evidenced by the excessive soot appearing around the flame.

This soot signifies that there are unburned hydrocarbons in the flame, a hallmark characteristic of a carburizing environment. The small, defined inner cone in this flame type appears when there’s a dominating presence of acetylene, while the soot produced suggests a rich cutting environment that can affect the quality of the cut. In oxyfuel cutting, achieving the correct flame type is crucial for ensuring proper cutting and minimizing the negative impacts that the wrong flame characteristics can have on the material being worked with.