A critical and costly factor in the basic oxygen steelmaking process is the “Skimming” of desulfurized iron prior to charging the furnace. Liquid iron is treated with minerals to remove sulfur from the melt. The sulfides then travel to the surface as a slag and are skimmed from the iron ladle using a mechanical rake. It is critical to remove the impurities so as to meet the steel cleanliness requirements of the quality grade, however, over skimming costs the steelmaker time and yield – the two things he can never get back.
Connors Industrials was challenged to develop a product which would make the process measurable, so that the steelmaker could control the process and improve quality, costs, and throughput. In 2007, the first Skim Vision system was put into operation.
Using advanced cameras, housed in our custom designed extreme environment enclosures, the Skim Vision software package measures the digital intensity of the iron surface. The system centralizes several variables such as hot metal temperature and chemistry, and finished product requirements, and can calculate a required cleanliness level for the skim, as directed by shop operations management. The system adds consistency and control to the skimming process and provides operators the tools they need to maximize quality and production and continue to improve the process.
Connors Industrials has Skim Vision systems in nearly every integrated steel shop in the United States. The system is monitored by Connors Industrials personnel daily, and customized reports are issued to our customers so that they may better manage their operations.
Improved quality. The sulfur conformance for heats entering the secondary processing station were as follows:
• 16% increase in sulfur conformance on .010 S max.
• 67% increase in sulfur conformance on .005 S max.