著者
竹内 勝治 中安 静雄 中村 授
出版者
一般社団法人 軽金属学会
雑誌
軽金属 (ISSN:04515994)
巻号頁・発行日
vol.18, no.11, pp.586-592, 1968

Copper concentrate-ores were generally filled in jute bags for transportation by ships and trains from Peko Mines Co., Australia to Sumitomo Metal Mining Co., Japan. The rationalization of shipping works for the ores was required, because there were dangers of ignition of accumulated bags due to heat generation of the filling ores when they were moistened and exposed to high atmospheric temperature.In February 1967, the "Spensa-maru" which had been built for exclusive transportation of copper, zinc, and lead ores, was put in commission. The ship solved the above problems by the application of palletization for avoiding the heat generation and ignition and also getting rationalization of shipping work.In designing the pallets, there were no other proper means than assuming uniform distribution of the load on the pallets. However, the practical distribution of the load was not always uniform. Sometimes, the stresses in frames are higher than those of calculated values; or deformation of lower deck-board of second floor pallet is caused by concentrated load due to rugged arrangement of jute bags. However, these stresses or deformation shall be neglected in the practical work, if they are small.As being understood from the above facts, the loading test must be conducted with the practical loads.Of course, special care shall be taken in the operation of fork-lift trucks, and the pallets must be equipped with replaceable parts against damages by accidents.