Three types of flames in gas welding

We have seen the overview of a welding process, Arc welding process and Gas welding process with the help of our previous posts.

Let us get more in depth and understand now the types of flames in Gas welding with the help of this post.

Types of flames in Gas welding  

The types of flames are displayed here in the following figure.  The correct adjustment of the flame is very important for the production of satisfactory weld. Welding flames can be classified into the following three categories as mentioned below.   

1. Neutral or balanced flame 

2. Reducing or carburizing flame 

3. Oxidizing flame

Neutral or balanced flame - Salient features 

Equal amount of Oxygen and acetylene 

Balanced flame 

Application areas mainly stainless steel and mild steel 

Generates Less Smoke & Sparkle 

Flame inner Cone will have a temperature of 3200 °C approximately

Flame outer envelope will have a temperature in the range of 1200°C to 1300 °C. 

Oxidizing flame - Salient features 

Excess amount of oxygen 

Inner cone will be less luminous and shorter 

Outer envelope will be shorter and narrow 

Applications areas mainly copper, brass and zinc 

Inner Cone will have temperature 3300 °C Approximately 

Outer envelope will have a temperature in the range of 2200°C to 2500 °C 

Reducing or carburizing flame - Salient features 

Excess amount of acetylene 

This flame will have three sections i.e. Inner cone, Intermediate cone and Outer envelope 

Inner cone will have temperature 2900 °C approximately 

Intermediate Cone & Outer Envelope will have temperatures in the range of 1600°C to 1800 °C 

Application areas - High Carbon steel and Cast iron 

We will see the difference between Arc welding and Gas welding in our next post. 

Reference 

Engineering Practices by Mr. S. SUYAMBAZHAHAN