The thermal lance is an industrial thermal cutting tool that uses pressurized oxygen to generate temperatures of up to 7.000 °C. Its power allows it to melt, cut, or pierce high-resistance materials, such as steel, concrete, or stone. It is primarily used in demolitions, mining, metallurgy, shipbuilding, and industrial rescue.
What is a Thermal Lance?
A thermal lance, also known as an oxygen lance or burning bar, is a tool designed to cut or melt extremely hard materials through a controlled chemical reaction.
It consists of a steel tube filled with metal rods (made of iron, steel, aluminum, or magnesium), connected to a source of compressed oxygen.
When the tip of the lance is ignited and oxygen is released, an exothermic reaction occurs, generating a continuous jet of heat. This reaction raises the temperature to over $3,500\,^{\circ}\text{C}$ ($6,332\,^{\circ}\text{F}$), potentially reaching $7,000\,^{\circ}\text{C}$ under optimal conditions.
Thanks to this principle, the thermal lance can melt, cut, or pierce any solid material, even in underwater environments or with low visibility.
How a Thermal Lance Works
The operation of a thermal lance is based on the principle of iron oxidation in the presence of oxygen. The operational process follows four essential steps:
- The end of the lance is heated with a torch or a heat source.
- The oxygen flow is opened, which streams through the inside of the tube.
- The oxygen reacts with the metal of the rods, producing intense combustion.
- The resulting temperature melts or pierces the material in contact with the tip.
This reaction is self-sustaining, meaning that once ignited, the lance does not require an external flame to continue working. This characteristic makes it especially useful in difficult environments where other cutting technologies are not effective.
Industrial Applications
The thermal lance is a frequently used tool in operations requiring high power and precision in cutting resistant materials. Its main uses include:
- Industrial Demolitions: It allows for cutting beams, steel structures, and reinforced concrete without generating vibrations.
- Mining and Metallurgy: It is used to open channels, clean furnaces, or unblock solidified tapholes.
- Civil and Naval Construction: It is effective for cutting and dismantling metal structures, both on the surface and underwater.
- Locksmithing and Rescue: It enables the rapid opening of high-security locks and safes.
The versatility and power of the thermal lance make it an indispensable resource in sectors where material resistance prevents the use of conventional methods.
Advantages of Using a Thermal Lance
The thermal lance offers several technical benefits that justify its widespread adoption in industrial settings:
- It can cut practically any material, metallic or non-metallic.
- Its setup is fast and requires minimal equipment: a lance, an oxygen source, and an ignition source.
- It does not generate vibrations, reducing the risk of structural damage.
- It allows for working underwater without loss of effectiveness.
- It is portable and economical, especially compared to industrial plasma or laser systems.
Furthermore, as it does not rely on electric current, its use is viable in locations where power supply is limited or non-existent.
Safety and Usage Precautions
Due to the temperatures it reaches and the pressure of the oxygen used, the thermal lance must be handled under strict safety protocols.
The operator must be properly trained and have the appropriate personal protective equipment, which includes a welder’s mask, flame-retardant gloves, a filtering mask, and heat-resistant clothing.
Before each use, it is essential to check that hoses, valves, and gas cylinders are in good condition. The work must be performed in a well-ventilated environment, with rigorous control over the oxygen supply.
Once cutting is finished, it is recommended to close the gas flow gradually to prevent backfires or explosions due to overpressure.
Differences Compared to Other Cutting Methods
Unlike traditional methods such as plasma, laser, or oxyacetylene cutting, the thermal lance does not depend on the material’s electrical conductivity or a specific mix of combustible gases.
This allows it to work on mixed, rusted, or non-conductive surfaces where other technologies are inefficient.
Additionally, its superior working temperature makes it more suitable for heavy demolition, industrial maintenance, or rescue tasks.
The thermal lance is a robust, versatile, and highly efficient cutting tool used in sectors that require working with extremely hard materials.
Based on the controlled oxidation of iron with oxygen, its technology enables fast, precise, and safe operations in demanding industrial environments.
Its effectiveness has ensured that, since its invention in France during the 1930s, it remains one of the most reliable solutions for industrial cutting and piercing, surpassing more modern methods in adaptability and resilience.
Technical Summary
| Feature | Details |
| Working Temperature | Between $3,500\,^{\circ}\text{C}$ and $7,000\,^{\circ}\text{C}$ ($6,332\,^{\circ}\text{F}$ and $12,632\,^{\circ}\text{F}$) |
| Applicable Materials | Steel, concrete, stone, ceramics, and metal alloys |
| Sectors of Use | Demolition, mining, smelting/foundry, shipbuilding, and rescue |
| Basic Requirements | Oxygen source, controlled ignition, and certified operator |
FAQ – Frequently Asked Questions
What temperature does a thermal lance reach?
Between $3,500\,^{\circ}\text{C}$ and $7,000\,^{\circ}\text{C}$, sufficient to melt steel or stone.
Can it be used underwater?
Yes, its ignition remains active even in submerged or high-humidity environments.
What gas does it use?
It uses compressed oxygen to maintain the internal combustion of iron.