100種類の自動車部品にシェルモールドを適用した結果について

抄録

  Numerous problems related to equipment and casting techniques were encountered in carrying out a continuous flow of operations by the shell mould process from one pouring on a conveyor to shakeout, trimming and blackenig of approximately 100 different kinds of automotive parts, whose weights as-cast range from 0.04kg to 47kg.
  In the layout of shop facilities, consideration was given to effect an arrangement of highly effecient equipment and to utilize the length and width of the shop with the aim of accomplishig high productivity. This resulted in (1) the adoption of the vertical pouring system on all parts in order to perform wasteless pouring of continuously tapped molten metal, raise productivity within a limited floor space and improve quality, (2) setting up of a control center so as to enable a smooth pouring operation for a combination of parts of varying sizes, and (3) equipping a direct reading spectrometer to control the molten metal for parts of varying material quality and thickness.
  On problem related to the quality of castings, for instance, (1) the internal defects of the water-cooled cylinder head was eliminated by improvement of the gate ratio and the adequate control of the pouring temperature and speed in the casting plan, and (2) defects arising from dross formation on the ductile cast iron crankshaft inherent of such metal have been eliminated by controlling the pouring temperature, carbon equivalent and the amount of Mg additives. As with defects arising from shrinkage cavities these proved effective.
  With foundry setup and casting technique mentioned, a striking advance in production has been observed, and production in terms of cast iron output in 1961, after installation of equipment, increased 2.7 times per square area and 2.2 times per man, as compared with that of 1956.