The article focuses on the issue of improving the efficiency of a Foundry Degassing Unit (FDU) via operational testing of aluminium alloys during casting at MOTOR JIKOV Slévárna a.s.. As part of the research, the efficiency of the refining process in the FDU was assessed. The main emphasis was placed on determining the moment of the greatest decrease in the hydrogen content in the melt and whether it is possible to shorten the refining cycle. The values of the Dichte Index were determined, on the basis of which the degassing curve was plotted and the progress of the melt degassing was assessed. To ensure the required quality of castings, the maximum allowable value of the Dichte Index ranged from 3 to 4%. During the process, the temperature drop during the refining cycle was also determined. The total temperature drop from pouring the melt into the ladle to the end of refining ranged from 26 to 32 °C, which is within the acceptable limits of the foundry. Based on the knowledge resulting from the operational experiments, recommendations were formulated to optimize the refining technology at the FDU for the MOTOR JIKOV Slévárna a.s. foundry.

Die Casting Division MOTOR JIKOV Slévárna a S Kněžskodvorská 2277 370 04 České Budějovice Czech Republic

Environmental Research Department Institute of Technology and Business in České Budějovice Okružní 517 10 370 04 České Budějovice Czech Republic

Faculty of Materials Engineering Silesian University of Technology Krasinskiego 8 40 019 Katowice Poland

University of West Bohemia Univerzitní 2732 301 00 Plzeň Czech Republic

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