What type of flame has an excess of fuel when cutting?

A carburizing flame has an excess of fuel when cutting because it provides more acetylene (the fuel gas) than oxygen in the combustion process. This type of flame is characterized by its yellowish tip and produces a softer flame that can effectively reduce metal oxides. In cutting applications, the carburizing flame is beneficial for materials that require a softer, more controlled heat, as it minimizes the risk of oxidation and can produce a cleaner edge on the metal. This is particularly advantageous when working with materials that are sensitive to oxidation, such as certain steels and other alloys.

In contrast, a neutral flame has a balanced mix of fuel and oxygen, making it suitable for general welding and cutting tasks without introducing excess carbon or oxygen to the workpiece. An oxidizing flame has more oxygen than fuel, which can lead to oxidation and is typically used for certain types of welding but not cutting in most applications. An inert flame refers to a flame created using an inert gas, which does not have the chemical activity of combustion and is not applicable to the cutting process in the same context.