Welding Flames

Welding Flames: Types and Their Uses

Welding is a process where heat is used to join metals together. Gas welding is one of the oldest and simplest ways of welding. It uses a flame created by mixing flammable gas (like acetylene) and oxygen. This flame heats the metals until they melt and join together.

In most cases, oxy-acetylene is used in gas welding because it can reach very high temperatures (up to 3200°C). This article explains the different types of welding flames and their specific uses in welding.

Types of Welding Flames

There are three main types of welding flames:

1. Neutral Flame
2. Carburizing Flame
3. Oxidizing Flame

Each type of flame is used for different metals and welding purposes.

1. Neutral Flame

• What It Is:
  A neutral flame has an equal mix of acetylene and oxygen. It burns cleanly and doesn’t add extra carbon or oxygen to the metal being welded.

• How It Looks:

  • Has a clear and sharp inner cone.
  • The temperature at the cone tip is about 5850°F.
  • The outer flame temperature is around 2300°F.

• Uses:
  Neutral flames are used for welding metals like mild steel, stainless steel, cast iron, copper, and aluminum.

2. Carburizing Flame

• What It Is:
  A carburizing flame has more acetylene than oxygen. This creates a flame with an extended “feather” edge.

• How It Looks:

  • A bright blue inner cone with a white middle cone.
  • Makes a soft, hissing sound when burning.
  • The temperature at the inner cone tip is about 5700°F.

• Uses:

  • Used for welding metals that benefit from extra carbon, like high-carbon steel.
  • Helps in soldering silver and low-heat applications.

3. Oxidizing Flame

• What It Is:
  An oxidizing flame has more oxygen than acetylene. It burns hotter and produces a sharp, pointed flame.

• How It Looks:

  • The inner cone becomes smaller and purplish.
  • Makes a loud, burning sound.
  • The temperature at the cone tip is around 6300°F.

• Uses:

  • Ideal for metals like zinc, copper, manganese steel, and cast iron.
  • Not suitable for steel, as it can make the weld brittle and porous.

MAPP Gas Welding Flames

MAPP gas is another type of fuel used in welding. It produces strong flames and is easy to adjust.

• Flame Types:

  • Carburizing Flame: Contains more fuel than oxygen.
  • Neutral Flame: Balanced fuel and oxygen mix, good for welding steel.
  • Oxidizing Flame: Burns hotter with extra oxygen.

• Uses:

  • MAPP gas is great for welding aluminum and other oxidized alloys.
  • The flame is easier to control, making it suitable for brazing and soldering.

Why Is Gas Welding Popular?

• Gas welding is portable and doesn’t require electricity, making it useful in remote areas.
• It is cost-effective and works well for tasks like welding steel sheets, bending metal, and brazing.
• Despite technological advancements, oxy-acetylene welding is still widely used because it’s simple and versatile.

Conclusion

Gas welding is a reliable and flexible method for joining metals. Understanding the different types of welding flames (neutral, carburizing, and oxidizing) is essential for producing strong and durable welds. Whether you’re working with steel, copper, or aluminum, choosing the right flame ensures a smooth and effective welding process.