Energy Audit and Cost Saving in an Aluminum Sand Casting Foundry

The aim of this investigation was to audit and assess the energy consumption and energy efficiency of casting process in an aluminum sand casting foundry. Energy measurements took place by meter readings, on daily and weekly basis and by half hourly electricity readings provided by the supplier. At the same time all foundry operations were monitored closely to follow variables with the help and explanation of operators and the managers. The yield was also measured by dividing the final weight of castings with the input weight of the material. Data analysis took place through calculating and comparing the energy consumption of the foundry on a daily and weekly basis. Observations and calculations suggest that for this foundry energy efficiency can be increased and cost of production may reduce by adjusting daily production to a minimum of 300 kg of finished product per day. This study also shows further energy saving is possible by management control and personnel awareness, changing the foundry layout and speeding the casting operation to avoid delays, insulating furnace walls and covering the top when the furnace is not in use and keeping furnace temperatures as low as possible during melting and holding and avoiding unnecessary holding overnight and at weekends. The yield within the foundry varied from 40% to 55%. Casting operation can improve to higher yield of about 55% if simulation used more often to its full capacity with potential material and further energy saving.