Thermal lance

From Wikipedia, the free encyclopedia

Thermal lance in use, cutting apart a railroad bridge to prepare for replacement.
Thermal lance in use, cutting apart a railroad bridge to prepare for replacement.

A thermal lance or thermic lance or burning bar is a tool which burns iron in an oxygen rich environment to create very high temperatures for cutting. It consists of a long iron tube packed with iron rods, which are sometimes mixed with aluminum or magnesium rods which increase the heat output. One end of the tube is placed in a holder and oxygen is fed through the tube.

The far end of the tube is usually lit by an oxyacetylene torch. It can also be lit by an electric spark, in which case the tube is connected to one terminal of a battery and the other terminal is connected to a copper electrode. The end of the tube is then rubbed against the copper electrode to produce sparks, which ignite the lance.

An intense flame is produced at the lit end and can be used to rapidly cut through a variety of thick materials including steel and concrete. The tube is consumed, so every few minutes the operator shuts off the oxygen, discards the remaining stub of a lance tube, and starts using a new one.

A thermal lance does not contain thermite.

Thermal lances burn at 7000 to 8000°F (3870 to 4420°C)[citation needed], melting even rocks.

[edit] Appearances in fiction

The thermal lance is used in popular entertainment media, including:

  • In the Michael Mann-directed film Thief, a thermal lance is featured in a scene where the main character must break into an exceptionally dense and secure safe.
  • In the film $ (A.K.A. "Dollars" and "The Heist" ) the bank manager uses a thermal lance to release an employee who was locked into the bank vault.
  • In the TV series Heist, the character Ricky uses a thermal lance to break into an armored truck.
  • The Bank Job (2008) recreates a hushed-up robbery in London in 1971 where thieves tunnelled under a bank and used a lance to break into the bank vault.
  • CSI, first season, episode 16 entitled "Face Lift" as a means for opening a safe
  • Extensively used in the British TV series Ultimate force, where the SAS troop would use them to burn through metal bars and concrete walls.

Popular depictions of thermal lances sometimes exaggerate its capabilities. In the movie The Score, the character Nick Wells (played by Robert De Niro) uses a thermal lance to cut a hole in the top of a safe, to avoid the safe's glass relocker device. The television show MythBusters, in the segment Water Safe, demonstrated that drilling into a modern safe using thermal lance takes far longer than depicted in popular accounts. Also, the heat from the thermal lance completely destroyed the items inside. They concluded that using a thermal lance for safe-cracking is plausible, though impractical. However see U.S. Patent 3,612,166  which says that burning bars are a significant threat to vault doors.

[edit] Fictional uses with wrong meanings

The term "thermic lance" or "thermal lance" is occasionally used in science fiction to mean a type of ray gun.[citation needed]

In the videogame X-COM: Terror from the Deep, a "thermic lance" is a melee weapon using a very hot quickly rotating drill-like blade: see the Ufopaedia entry for `thermic lance'.