Model of Linz-Donawitz (L-D) converter, c. 1970

The availability of cheap "tonnage" oxygen has revolutionized steel-making.Several new processes have been developed with great success and the simplest, and more successful, is the L-D process. A crucible- like vessel is used and a high speed jet of oxygen is injected into molten pig iron from a water-cooled nozzle above, rapid oxidation of carbon occurs, converting the pig iron into steel. Other oxygen steelmaking processes include the Kaldo and the Rotor.