The “Alcoa Filter System AFS”: A cost effective solution for enhanced CFF performance

Abstract

Ceramic Foam Filtration is a well-known process for effectively removing inclusions from the molten metal in DC casting. It has however limitations for the removal of small particles. In industrial application and for high metal flowrate 40 ppi (porous pore per inch) is almost the limit. Filter pads with fine pores are available but the priming is more difficult. Solutions that have been developed to improve priming of the fine pore filter pads are complex and expensive. A new priming technique was developed and tested both in laboratory and plant conditions. Excellent filtration performance was attained. It gives the possibility for the cast house to produce value added products with great flexibility and cost effectiveness. The technology is now available for plant implementation. This technology gives opportunity for plants that have no space for a bed filter to have similar inclusions removal performance result for specific alloys.