In steel and casting industries, the transportation of hot and heavy molten metal requires a transport control system that can suppress molten metal vibration and transport the metal to its destination quickly to ensure safety and efficiency. Considerable research is being conducted in this area. In particular, when transporting molten metal by an overhead crane, the rod suspending the ladle and the molten metal inside the ladle perform a double pendulum motion which produces vibration of the molten metal that is complex and difficult to control. During the transportation of molten metal, this vibration can cause dangerous overflow of the molten metal, and subsequently product degradation, such as slag inclusion.

  This study confirms that the proposed control system is useful for improving the intuitive operations by the operator. Using statistical methods, the operability of the system was investigated in relation to the degree of experience gained by the operator through repeated operations These finding verify the usefulness of the proposed control system for transporting molten metal at casting sites.

  The 28cm howitzer hoop cast iron cannons, which played a significant role during the Russo-Japanese War, were initially prototyped at the Osaka Arsenal in the mid-Meiji period. Refined Kamaishi pig iron was melted in a reverberatory furnace and cast using molds with water-cooled cores. By the end of the Meiji period, the canons were successfully produced without defects using Italian Gregorini pig iron. However, detailed information about the manufacturing process is not available, possibly due to military secrecy. This report hypothesizes that controlling the graphite structure was a measure to counteract strength deterioration, but unfortunately, the technical methods used could not be fully unraveled.