24 Jan 2003
The world's first production laser-assisted oxygen system that can cut 50 mm-thick steel is installed at a US shipyard.
Engineers have installed the world's first production laser-assisted oxygen (LASOX) system at a US shipyard. Bender Shipbuilding, which is based in Alabama, is using the technique to cut thick steel plates with less than 2 kW of laser power.
The process looks set to find many applications in cutting thick steel plates, a market that laser technology has yet to have any impact on.
LASOX combines a high-power laser with a jet of oxygen. The area of steel illuminated by the laser beam is heated to its ignition temperature of approximately 1000 °C. Then a supersonic oxygen stream is fired through a nozzle at the spot to initiate cutting, so that the laser in effect replaces the fuel gas used in an oxy-fuel torch. It means that at least 50 mm-thick steel can be cut, whereas current laser technology is only said to be effective up to half of this thickness.
Researchers at UK-based BOC Gases invented LASOX and the company owns a trademark and patent rights to the technology. After eight years of research between BOC and the University of Liverpool, it licensed the technique to Alabama Laser Systems, US, for commercialisation.
Following a year-long development with fellow US company Cutting Edge Metal Processing, a Tanaka 6 kW carbon dioxide laser system adapted for LASOX was installed at Bender in November last year. Operators have already used the system to cut 75 mm-thick production parts from mild steel and their goal is to increase this to 100 mm.
It is said that LASOX allows steel cutting with much lower laser power than is normally needed. For example, it is claimed that it can cut through at least 50 mm-thick steel using just a 2 kW emission or less. Both square and bevelled edges can be manufactured.
Jack Gabzdyl, BOC's market development manager, believes that LASOX could have a big impact in metal processing. "The process could become a modern alternative to traditional thick-section profile cutting methods such as oxy-fuel," he said.
Bender Shipbuilding's R&D manager Pat Cahill, who is also programme manager for the LASOX project, said: "A year ago, cutting steel thicker than 50 mm with a 2 kW laser would have been unheard of. This process has the potential to cut plates as thick as 100 mm, [whereas] high-powered plasma cutting is limited to 75 mm. [LASOX] opens up the possibility of a new generation of stell ships that are stronger and cheaper to build."
Cahill also told Optics.org that the team was currently looking at fiber-delivered options to increase the flexibility of the LASOX system. He added that the technique could be applied to other types of laser, provided that the spot size can be controlled.
US manufacturing companies Caterpillar and General Dynamics-Electric Boat are commited to implementing LASOX technology, and the installation at Bender is said to be so successful that this programme has been brought forward by three months. This should see full LASOX installations early this year at Caterpillar to produce heavy-duty mining equipment and at General Dynamics-Electric Boat for submarine building.