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Show PAPER NO. 29 Aluminum Heating Technique Using an Immersion-tube Burner Yasuhisa Nakamura Toho Gas Co., Ltd. R&D Institute I. Trend of Demand for Aluminum Die Casting Aluminum products account for about 90% of all die casts, 70% of which are for automobile parts. The demand for aluminium die casts is expected to keep growing because they are becoming preferred by auto makers as they try to reduce the weight of their cars. Auto parts are increasingly produced in overseas plants, while in the Japanese market, there is steady demand for high-quality and high-performance cars. This will help increase demand for aluminium die casts of a higher qUality. On the other hand, the current production of aluminium die casts for industrial machines and tools, electric appliances and communications equipment is small, and future demand is not expected to increase significantly. Therefore, it can be said that the trend of demand from the auto market determines the future for this market. ll. Heating by an immersion-tube The immersion-tube heating method, since it ftrst received recognition in the early 1980s for aluminium die casting, had been improved repeatedly. In spite of these efforts, it did not become popular because the immersion tube had to be replaced frequently and maintenance was difficult. As attention was paid to fine ceramics which is used for a burner tube, various types of ceramics were developed. As a result, materials which feature various heat resistant characteristics have been developed for actual use. These materials cleared one of the problems of the immersion-tube, i.e. the short tube life, resulting in considerable improvement of this immersion-type heating method. 1 |