Iron has a property called "auto-ignition". For cutting, that property is the mechanism for the oxy-fuel cutting process. When iron is heated to the auto-ignition temperature 1,315 degrees Celsius (2,399 degrees Fahrenheit), then the iron will ignite, and "burn" in normal atmosphere, and at lower temperature of 900 degrees Celsius, or less, in the presence of pure oxygen.

The method of heating is irrelevant, because the chemical reaction with the oxygen is the primary mechanism of the cutting. For standard oxy-fuel cutting, the metal is cut almost entirely by that exothermic chemical action. The surface of the iron is melted by the heat of the oxidation reaction. The force of the oxygen stream quickly moves the oxide which is produced away from the cut-zone. This ensures a clean liquid iron surface on which the oxygen stream impinges. The heat to keep the cut going - once it has started - is provided partly by the burning oxygen plus fuel mixture, and partly by the heat from the chemical reaction of the heated iron with the oxygen. The new cutting process uses induction heating of the iron/steel instead of burning oxygen plus fuel. Oxidation of the iron is still the primary heat source to melt the iron, and the oxygen stream force removes the oxidized iron, so the oxygen can continue to reach the melted iron. Induction is many times as efficient for heating the iron to the auto-ignition temperature. So, a cutting system consisting of the induction heating and then followed by a stream of oxygen can cut many times faster than oxy-fuel. Also, a combination of induction heating and a plasma torch can heat the metal even faster. So the hybrid induction-plasma process has also been invented. The plasma, while very hot and precise, is not an efficient heating mechanism. But, by combining the induction with plasma, the high quality of a plasma cut is achieved, but the cutting speed can be 10X, or more, faster than using the plasma alone.

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