窄流道封闭式叶轮的制壳工艺改进

Improvement of Shell-making for Narrow Flow-channel Close Impeller

生产封闭式窄流道叶轮,为降低成本,可避免使用水溶砂芯,采取直接制壳的方法。经过生产实践,沾3次面层后,在进出水口部灌浆砂,中间灌干砂,既可保证铸件质量,减少废品,同时容易去除流道内的废砂。

Direct shell-making method was adopted in producing narrow flow-channel close impeller to avoid using water-soluble sand core and to reduce production cost.The practical production shows that the shell-mold was poured with sand slurry at inlet and outlet and was poured with dry sand at middle after stuccoing three layers face sand,which not only ensure the quality of the castings to decrease the scraps,but also easily remove the shell-mold sand in flow-channel.