What a thermal lance is, how it works, and when to use it in steel, construction, mining, non-ferrous foundries, naval, railway, and rescue sectors. You will find real cases, basic parameters, advantages, limits, and best practices. The objective is for you to make a clear decision for your work without wasting time.
What is a Thermal Lance?
Let’s start with the essentials. If you manage maintenance, construction sites, or scrapping, you need a definition you can explain to your team.
In short: It is a steel tube packed with rods that, using pressurized oxygen, generates > 3,600 °C via an exothermic reaction. It melts and pierces steel, stainless steel, reinforced concrete, aluminum, and copper. It is ignited with a torch and operates solely on oxygen, without electricity.
How Thermal Lances Work
Performance doesn’t happen by magic. It comes from controlling oxygen, lance diameter, and technique. You ignite the tip. You open the oxygen within the correct range. Iron oxidation releases heat and creates a fusion pool that advances where you aim. If you understand these three factors, the work is clean and fast.
- Torch ignition and oxygen opening between 4 and 9 bar.
- Reaction: $$Fe + O_2 \rightarrow \text{iron oxides} + \text{heat}$$
- The jet melts and expels slag.
- Diameters: 12 mm and 17.3 mm. Lengths: 1.5 to 3 m.
Indicative Consumption:
- 12 mm: ~1 m³ of O₂ in 4 to 5 min.
- 17.3 mm: ~3.2 m³ of O₂ in ~20 min.
Main Industries Using Thermal Lances
Steel Industry
In steel, downtime costs money. The lance comes in when a tap hole is blocked, when a ladle arrives with crusts, or when scrap metal won’t yield to the shear. We look for agility, safety, and refractory protection. This is where it makes the difference.
- Opening tap holes in blast furnaces and electric arc furnaces in minutes.
- Cleaning ladles, converters, and continuous casting units with angle and distance control.
- Cutting heavy scrap for recycling: Axles, frames, and presses.
- Type T for general scrap. Type W for stainless steel and high thicknesses.
Construction and Demolition
On-site, the priority is control and reduced vibration. When the breaker raises dust without advancing and the angle grinder can’t reach, the lance solves it with a clean, planned cut. Useful in confined spaces and on mixed elements containing steel and concrete.
- Demolition of reinforced concrete in a single intervention.
- Cutting thick beams and columns in confined spaces.
- Piles and sheet piles in ports and docks. Underwater work.
Mining
Mines demand tools that don’t surrender to size. When there are hoppers and chassis with great thickness, or rock where vibrations are not permitted, the lance provides rapid fusion and access without giant machinery.
- Dismantling high-tonnage hoppers, chutes, and chassis using Type W.
- Thermal drilling in hard rock when percussion is not viable.
Non-Ferrous Foundries
In aluminum and copper, the challenge is opening passages without mistreating refractories and cleaning parts with sintered sand. The lance, operated well, maintains thermal control and avoids damage to expensive components.
- Opening tapping passages with controlled combustion.
- Cleaning sintered sand and encrusted cores in cast parts.
Naval and Shipbreaking
In scrapping, the winner is the one who cuts thick sections with minimal logistics. Beaching area, dry dock, or shipyard. The lance works with humidity and salt spray without depending on power grids. It allows for sectioning and freeing seized parts to recover valuable material.
- Sectioning keels, ribs, and bulkheads from 50 to 100 mm.
- Freeing corroded shafts, pins, and propellers.
- Work on beaches or dry docks without electricity.
Railway and Infrastructure
On the track, every minute counts. A rail cut on time prevents delays and penalties. On bridges and metal sections, low vibration and environmental control are sought. The lance offers both.
- Cutting rails and check rails with very low times.
- Dismantling metal bridges and sections with reinforced concrete with lower vibration.
Rescue and Emergencies
When there are victims, the goal is to clear a path quickly and safely. The lance generates access in plates, shipping containers, and walls. It also acts underwater when other tools fail due to flooding or mud.
- Opening holes in containers, plates, and walls after collapses.
- Work underwater or in floods with a portable oxygen kit.
Operational Advantages
This is what you will notice day-to-day. Fewer stops, greater material reach, and rapid setup. Few parts, little transport, direct impact on deadlines.
- Material versatility in a single intervention.
- Fast start-up with lightweight equipment.
- Low vibration and less noise than percussion tools.
- Underwater operation.
- Simple logistics with oxygen bottles.
- High precision with trained personnel.
Limitations and Safety
It yields results if clear rules are respected. Pressurized oxygen demands order, PPE, and ventilation. A good job starts with a checklist and ends with hot-spot control.
- High-pressure oxygen: Procedures and work order.
- Spatter and thermal radiation: Complete PPE.
- Fumes and particles: Forced ventilation in enclosed spaces.
- Fire risk: Remove combustibles and prepare a water line.
- Thermal affect on surroundings: Protections and cutting plan.
- Only trained personnel with protocols and checklists.
Equipment and Parameter Selection
The choice defines the result. Define diameter, lance type, and pressure according to material and thickness. Correct adjustment reduces consumption and improves the cutting front.
- 12 mm: General work and medium cuts. 4 to 5 min per rod. 5 to 6 bar.
- 17.3 mm: Concrete and thick masses. ~20 min. 6 to 7 bar.
- Type T: Scrap and cleaning adhesions.
- Type W: Stainless, high thicknesses, reinforced concrete.
- Lance holder with lever and flashback arrestor. Stable regulator.
- Hose 3/8″ to 1/2″ to ensure flow rate.
When to Choose a Thermal Lance
Not everything requires a lance. Use it when other methods slow down or complicate the job. These cases are clear and repeated in the field:
- Mixed material difficult to separate on-site.
- Reduced space or complex access.
- Work underwater or with high humidity.
- Critical plant shutdown with a short window.
- Risk from vibration in delicate structures.
Best Practices
Technique is trained. Rely on planning and simple habits. This increases safety and lowers the cost per cut.
- Cut plan and slag evacuation routes.
- Thermal protection of cables, hoses, and refractories.
- Pressure adjustment before ignition.
- Constant angle and smooth advance.
- Post-cut control: Hot spots and atmosphere.
- Recording consumption and times to improve.
If you are looking for measurable results in plant continuity, demolition, or rescue, the lance delivers when working with training, planning, and discipline. Choose the right diameter, define the pressure, protect the environment, and document every shift to improve.