CASTHOUSE SAFETY
Preventing Melting and Casting Accidents
The Aluminum Association has long made the safety and well-being of aluminium industry employees a top priority and hundreds of tonnes of aluminium are safely melted and cast every day in casthouses, foundries, recycling, and reclamation plants all over the world. However, there are inherent risks and hazards involved in the melting and casting of aluminium, the most significant of those being the risk of a molten aluminum explosion due to the contamination of water or chemical oxidisers in the casting process. These hazards can be minimised or eliminated entirely by careful attention to safe handling practices and the sharing of best practices. In 2017, the Aluminum Association undertook several initiatives to further safe aluminium industry workplaces related to molten metal management and additional information on these is below. 2017 MOLTEN METAL INCIDENT REPORT In November, the Association published its annual Molten Metal Incident Report reflecting that in 2016 there were 195 melting incidents involving aluminum reported. This report, while not a statistical representation of the industry due to its reliance on voluntary self-reporting, once again highlights the predominant hazards that result in explosions during molten aluminium management. Reports are categorised by Force Level (see Figure 1) and 176 Force 1
incidents, 18 Force 2, and one Force 3 incidents were reported. Of the 195 incidents reported, most occurred in the casting area (100 Force 1, 15 Force 2 and 1 Force 3) followed by the melting area (36 Force 1, three Force 2 and zero Force 3) (See Figure 2). Most casting explosions (84 of the 116) occurred at start-up; 45 occurring with Direct Chill (DC) casting, and 67 with sow / mold casting. As was typical of past years, most melting explosions occurred due to wet or contaminated scrap, with the second highest reason for melting explosions being wet alloying agents, with wet or oxidised Mg also being a major contributor. Common causes of explosions in DC casting were wet or insufficiently sized drain pans, wet starting blocks, lack of butt curl control, and submergence of the ingot head into water. The most common causes of explosions in Sow casting were wet or cracked molds. The remaining incidents occurred in the reduction area, (22) and the transfer area (18). In 2016 there were 18 injuries related to these events reported: 11 Minor and 7 Serious with no Fatalities (see Figure 3). Although 2016 had the highest number of incidents ever reported, the total of 18 injuries was the lowest total ever reported since the program began in the early 1980’s. This is also dramatically lower than the 56 injuries reported in 2015, which were all Minor, with no Serious injuries. The one Force 3 casting incident in 2016 resulted
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