In-block casting impeller with multi-blades and narrow flow-channel for centrifugal fans was conducted. Through adopting movable vane structure manufacturing inner core mould

in-block casting impeller was realized successfully

overcoming the problems in mould-release difficulty during in-block casting impeller with narrow flow-channel and closed structure. The impeller for centrifugal fans which is manufactured by the technology exhibits the features of not only high casting precision and high structural strength

desirable quality but also low cost and high product efficiency. Practical production shows that the technology can be widely used for the in-block casting impeller with different type multi-blades.