What is the recommended flame type for brazing?

The recommended flame type for brazing is the neutral flame. A neutral flame is characterized by a balanced ratio of oxygen and acetylene, resulting in a flame that neither oxidizes nor carburizes the metal being worked on. This balance helps ensure that the metals being joined do not suffer from oxidation, which can weaken the joint or lead to impurities in the brazed area.

Using a neutral flame allows for precise temperature control, which is essential for brazing, as it typically requires lower temperatures than welding. This kind of flame effectively melts the filler metal without affecting the base metals unduly, providing a strong and clean joint.

While oxidizing flames can lead to unwanted oxidation and are usually not suitable for brazing, carburizing flames can introduce carbon into the metal, which is also detrimental. A low-oxidation flame, although it might sound suitable, is not the standard terminology or flame type recognized for brazing practices. This makes a neutral flame the clear and correct choice for achieving optimal results in brazing applications.