Flame Cutting 101 at Kappa Engineering

Flame cutting employs an oxy-fuel gas flame to cut through metal. Learn more in this article.
flame cutting

Flame Cutting 101 at Kappa Engineering

Flame cutting is employed in various industries, from manufacturing, and agriculture to forestry, construction, and power generation. Flame cutting is suitable when manufacturing industrial products and structures made from iron or steel. Kappa Engineering uses flame cutting to manufacture parts for industrial applications.

The Flame Cutting Process

Flame cutting employs an oxy-fuel gas flame to cut through metal. The heat from the flame creates iron oxide, which is then removed by an oxygen jet, which cuts the metal.

Flame cutting is more efficient than plasma cutting, especially in projects with thicker metal. This helps to reduce production time and costs. Flame cutting works exclusively on metals that have carbon in them, which include carbon steel, low alloy steels and cast irons.

According to OpenLearn, the cutting torch has an oxygen jet surrounded by heating flames. “900cm3 of oxygen is required to oxidise 0.5 kg of iron”. This is the same principle used in a welding torch. 

Several neutral flames surround a jet of high-pressure oxygen in the centre. When the metal reaches 800°C, the oxygen is released by a quick-acting valve. “The cut quality is governed by the oxygen vent size, oxygen pressure, cutting speed and pre-heating flames,” they explain.

Flame Cutting Efficiency

Flame cutting is optimal for thick steel/cast irons when cost efficiency is paramount. The biggest benefit of metal flame cutting is that the process is affordable.it’s a process that is cheap to do. Flame cutting is easy to perform and does not rely on electricity.

The only elements needed to power a flame-cutting machine successfully are an oxygen tank, a torch, and a striker. Flame cutting is a powerful processor capable of cutting through thick materials like steel alloys, carbon alloys, and cast irons, making it most effective in these areas.

Slicing Metal

High heat (‘preheat’) and 99.5% pure oxygen are essential for this thermo-chemical process. Any decrease in purity (e.g. 0.1%) would slow the process by 10%, so pure oxygen is crucial.

ESAB, the world leader in welding and cutting equipment and consumables, explains, “While the source of the Oxygen may be pure, improper connections, bad hoses, or leaks of any sort can allow impurities in the system, thereby reducing the cutting speed.

Oxygen’s great purity creates a hazardous condition, requiring utmost caution when choosing apparatus and engineering tubing systems for its application. Safety is essential to Kappa. They follow all requirements and vital procedures when flame cutting.

Materials Best for Flame Cutting

Specific properties found in materials can make them easy or difficult to cut. These properties are always desirable when flame cutting:

  • the material is easily oxidisable at preheating temperature
  • it has a high heat of combustion
  • the melting point of oxides is below the melting point of the workpiece
  • the material has low-viscosity oxide
  • it has low thermal conductivity, also known as “ignition temperature”

Connect with Kappa

Talk to a representative today to find out which cutting method is suitable for your project. At Kappa Engineering, no matter the size of your project, we have the experience and tools to get it done. 

We will ensure that your project is completed with the best result and service. Contact us today to discuss your manufacturing needs. Kappa Engineering is the perfect partner for your business with our 24-hour delivery time on thinner and 48-hour delivery on thicker metals.

Learn more about plasma cutting services at Kappa Engineering.



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