Vacuum degassing of molten steel - where computer controls supply of oxygen into degassing vessel for efficient decarburising of plain or alloy steels (NL 7.1.81)

摘要

Oxygen is fed into the degassing vessel and the carbon content of the melt is continuously measured. During degassing, the pressure in vessel and the flow rate of the oxygen are simultaneously controlled so prescribed relationships exist between the pressure and the % C in the melt, and between the O2 flow rate and the % C. The % C in the melt is pref. calculated by determn. of the % C in the gas removed from vessel and deducting the latter value from the original % C in the melt. In the pref. plant, vessel is connected via a vacuum pump to a flowmeter and analyser which feed signals to a computer employed to adjust the flow of O2 into vessel. Used e.g. to reduce the carbon content of stainless steels without excessive loss of chromium.