Thermal lance#Appearances in fiction

File:thermic_lance_principle.svg |year=2021 |volume=60 |issue=21 |pages=7788–7801 |doi=10.1021/acs.iecr.1c00532|s2cid=236384938 |url=https://strathprints.strath.ac.uk/76441/1/Marti_Rossello_etal_IECR_2021_Numerical_model_for_the_combustion_of_a_thermal_lance.pdf }}

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One end of the tube is placed in a holder and oxygen is fed through the tube. The far end of the tube is pre-heated and lit by an oxyacetylene torch. An intense stream of burning steel is produced at the working end and can be used to cut rapidly through thick materials, including steel and concrete.{{cite web |url=https://www.thermiclance.com.au/what-is-thermic-lance/ |title=What is a Thermic Lance? |website=Australian Thermic Lance Company |access-date=11 July 2022}} The tube is consumed by the process within a few minutes.

Often used as a heavy duty demolition tool, the thermic lance is also used to remove seized axles of heavy machinery without damaging the bearings or axle housing. This technique is often used on the pins and axles of large equipment such as cranes, ships, bridges, and sluice-gates. In addition, thermal lancing is used to clean the bottom of steel furnace pots, which accumulate a skull layer of slag and iron during operation.{{cite web |url=https://www.aafintl.com/en/power-and-industrial/case-studies/environmental-products/optiflo/optiflo-thermal-lancing |title=Thermal Lancing case study - dust collector extends deskulling operation |publisher=AAF International |access-date=11 July 2022}}

{{See also|Melting-point depression}}

Steel, in the form of steel wool, can burn at atmospheric (20%) concentrations of oxygen because it has a high surface area-to-mass ratio and relatively low mass, which prevents the heat from being dissipated in the bulk of the material.{{cite web |url=https://www.livescience.com/60764-watch-steel-wool-burn.html |title=Here's How Steel Wool Burns (and Why It Looks Like the Death of Krypton |author=Emspak, Jesse |date=October 24, 2017 |work=LiveScience |access-date=11 July 2022}} When the oxygen concentration is increased, steel wool will burn faster.{{cite web |url=https://chem.washington.edu/lecture-demos/combustion-steel-wool |title=Combustion of Steel Wool |publisher=University of Washington, Department of Chemistry |access-date=11 July 2022}} Burning steel wool is simply the rapid oxidation of iron into {{chem|Fe|2|O|3|link=Iron(III) oxide}}; the thermal lance uses steel in the form of rods rather than wool, the rods will burn with a sufficiently high supply of concentrated oxygen.

The temperature at which a thermal lance operates varies depending on the environment.{{Cite book| last=LaGuardia | first=Thomas S. | title=The Decommissioning Handbook | chapter=Chapter 16.3: Characterization; Description of Select Technologies | pages=4‐46 | location=New York | publisher=ASME Press | year=2004 | chapter-url=https://books.google.com/books?id=Q7hbcjNRLxAC&pg=PT314 | isbn=978-0-89448-041-6}} Some estimates put the maximum temperature at {{convert|4500|C|F|abbr=on}},{{Cite book| last1=Kosanke | first1=B. J. | last2=Sturman | first2=B. | last3=Kosanke | first3=K. | last4=von Maltitz | first4=I. | last5=Shimizu | first5=T. | last6=Wilson | first6=M. A. | last7=Kubota | first7=N. | last8=Jennings-White | first8=C. | last9=Chapman | first9=D. | title=Pyrotechnic Chemistry | page=124 | publisher=Journal of Pyrotechnics | year=2004 | url=https://books.google.com/books?id=Q1yJNr92-YcC&pg=PA124 | isbn=978-1-889526-15-7 }} while others calculate it to be {{convert|2730|C|F|abbr=on}}.{{Cite journal| doi=10.1021/ie030729r | title=Model Analysis of Thermal Lance Combustion | year=2004 | last1=Wang | first1=Haorong | last2=Hlavacek | first2=Vladimir | last3=Pranda | first3=Pavol | journal=Industrial & Engineering Chemistry Research | volume=43 | pages=4703| issue=16}}

Thermal lances have been constructed for demonstration using foodstuffs (including bacon and dried spaghetti) as the fuel instead of steel rods; a supply of pure oxygen is more important to drive rapid oxidation than the fuel being burned.{{cite web |url=https://www.popsci.com/bacon/ |title=Bacon: the Other White Heat |author=Gray, Theodore |date=April 15, 2009 |website=Popular Science |access-date=11 July 2022}}{{cite web |url=https://hackaday.com/2011/02/11/thermic-lance-made-from-spaghetti/ |title=Thermic lance made from spaghetti |author=Nathan, Mike |date=February 11, 2011 |website=Hackaday |access-date=11 July 2022}}

Leo Malcher filed for a patent in 1922 entitled "Process of attacking compact mineral material, noncombustible in oxygen". The patent uses "a suitable disintegrating flux to act upon the material at the point where it is desired to attack it ... the fuel employed in the example to be described is metallic iron, and is arranged in the form of two concentric pipes". The annulus between the two pipes was filled with a flux (sodium carbonate borax and sodium chloride in equal proportions) and oxygen was supplied through the inner tube.{{cite patent |number=1494003A |country=US |inventor=Leo M Malcher |assign=Oxweld Acetylene Co |status=grant |gdate=May 13, 1924 |pridate=August 3, 1922}}

• {{annotated link|Thermite}}

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• {{US patent|3921542}} (oxygen-supplied thermic lance, invented by Ernst Brandenberger)
• {{US patent|3460223}} (device for fixing holes by method of smelting, especially into buildings, invented by Berczes et al.)

{{DEFAULTSORT:Thermal Lance}}

Category:Cutting tools

Category:Welding