| 摘要 |
<p>Rolls of cast iron with a hard shell and a soft core are cast in two stages. Through a funnel tube which emerges tangentially into the lower flask a roll mould with the slide closed is first filled with the material which is to form the shell. When the required thickness of shell has solidified the slide is opened and the remaining molten metal is drawn off into a casting ladle, the slide is reclosed, and finally the core metal is poured in through the funnel tube. The molten shell metal may be used for the next pour with minimum reheating.</p> |
