Design & construction of a low-cost furnace for melting non-ferrous alloys in the local foundry industry

Abstract

A study has been carried out on the types of construction and factors affecting efficiency of metal melting furnaces currently used in the non-ferrous foundry sector with the objective of developing an oil-fired furnace with improved efficiency and reduced constructional and operating costs. The project was initiated by the FDSI (Foundry Development and Services Institute) to meet a requirement of the small and medium-scale foundry industry. For example, there are many manufacturers of ornamental castings of Brass and Aluminum in the country, but they face the problem of the absence of a suitable furnace which could operate easily, efficiently and economically. Following a preliminary survey and assessment of technical data, the main factors which affect performance were identified. Based on this a new design was evolved, the main features of which are that the charge is pre-heated, the flame retained in the furnace for longer duration and the fuel pre-heated and subjected to better atomised spray. The furnace, commissioned at a local foundry, demonstrated a significant improvement in performance over conventional types and acceptance by industry. A key feature was the improvement in overall working conditions and working environment. Based on this experience, a further improved version has been constructed and installed at the Mechanical Engineering Department - University of Moratuwa as a demonstration model for industry.