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Why Engineers Often Choose Steel Wire for Thermic Lance Core?

Written by Author Name | 2025.08.21

Have you ever wondered why engineers often choose steel wire as the core material for Thermic Lances when aluminum or magnesium could theoretically burn hotter?

The answer isn't just about maximum temperature - it's about finding the right balance of chemical properties, structural integrity, and practical performance. While other metals might burn hotter in theory, they fail to meet the demanding requirements of real-world industrial applications.

In this article, we'll explore the three scientific reasons why steel wire remains the unbeatable choice for Thermic Lance cores.

What Exactly is a Thermic Lance?

About Thermic Lance 

A Thermic Lance (also known as a Thermal Lance or Burning Bar) is a high-temperature cutting tool that harnesses the power of oxygen and metal combustion. Think of it as a controlled metal fire that's hot enough to melt through virtually anything - from massive steel beams to reinforced concrete bunkers.

Basic Structure

The anatomy of a Thermic Lance is elegantly simple:

  • Outer steel tube: Acts as the lance body and oxygen delivery channel
  • Inner core: Packed with steel wires 
  • Oxygen supply system: Delivers pure oxygen at controlled pressures

Operating Principle

The magic happens through an exothermic oxidation reaction. When you ignite the steel wire tip with an oxy-acetylene torch and pump oxygen through the lance, the iron begins to burn in a spectacular chemical reaction:

4Fe + 3O₂ → 2Fe₂O₃ + massive heat energy

This reaction generates temperatures reaching 3,600°C, hot enough to melt through any industrial material you can imagine.

The 3 Main Reasons: Why Steel Wire Is the Preferred Core Material for Thermic Lances

Reason #1: Perfect Physical Properties

Steel's melting point of 1,538°C creates the perfect balance for Thermic Lance operations. Unlike aluminum which melts at just 660°C and loses structural integrity too quickly, steel maintains its form long enough for controlled combustion.

Multiple thin steel wires provide maximum surface area for oxygen contact, similar to how small ice cubes melt faster than one large cube. This design ensures uniform heat distribution across all wires, preventing cold spots and delivering consistent cutting performance throughout the entire steel wire core.

Reason #2: Economics and Availability

Aluminum wire costs approximately 3.5 times more than steel wire. Since Thermic Lances require numerous small steel wires packed inside the tube core, using aluminum would significantly increase the total material cost for each lance unit.

Reason #3: Optimal Combustion Performance

Steel wire delivers optimal combustion performance through a clean iron oxidation reaction that produces high energy output with only recyclable iron oxide as byproduct. Operators can easily control the burn rate by adjusting oxygen pressure, achieving predictable consumption and precise cuts while maintaining environmental responsibility through recyclable slag production and minimal water or noise pollution.

What If We Used Alternative Aluminum Wires?

The Advantages

  • Easier ignition (lower ignition temperature)
  • More intense reaction with potentially higher peak temperatures
  • Lighter weight for handling

The Disadvantages

  • Burns too fast: Consumption rate 2x higher than steel
  • Excessive smoke production: Creates visibility and ventilation problems
  • 3-4x higher cost: Not just materials, but total operational cost
  • Difficult to control: Unpredictable burn patterns risk precision
  • Safety hazards: Aluminum oxide fumes require special ventilation
  • Protective oxide layer: Forms at 550°C, blocking further combustion

The Hybrid Solution: You can also utilize hybrid lances that combine steel and aluminum wires to leverage the advantages of both materials - aluminum's easy ignition properties and steel's higher melting point can potentially reduce overall consumption rates. These specialized products offer benefits for specific applications, but require additional training and safety protocols.

Reference: Economical Alternative for Scrap Cutting: Thermic Lance with Aluminum Wires

Conclusion 

To sum up, there are 3 main reasons why steel wires are the ideal material for manufacturing Thermic Lance to ensure effective combustion goals. First, they have an appropriate melting point - not too low to be easily consumed, nor too high to hinder combustion, while providing maximum surface area for oxygen contact to support combustion. The second reason is economic efficiency and cost-effectiveness, as steel material costs less, while aluminum wires would be 3.5 times more expensive. Finally, steel wires enable powerful combustion due to the iron oxidation reaction generated from steel wires that are properly threaded within the inner steel tube. If you need to learn more about the product properties as well as Thermic Lance sizes, you can download information by clicking the link below.

About Daiwa Lance

Established since 1997, Daiwa Lance has positioned ourselves as a pioneer in thermic cutting and oxygen lancing technology. Based in Ho Chi Minh City, Vietnam, we have been providing quality customer service and products with advanced Japanese technology.

We maintain the highest quality standards with ISO 9001:2015ISO 14001:2015, and JIS G standards certifications. We have also expanded our reach globally, exporting to over 55 countries worldwide.

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