semiclosed-type impeller

例句：

1. 1. Thesemiclosed-type impeller is designedto improve the efficiency of the pump.
   这种半封闭型叶轮的设计旨在提高泵的效率。
2. 2.The impeller in this machine is madeof high-quality steel, ensuring longservice life.
   这台机器中的叶轮由优质钢材制成，确保了长寿命。
3. 3. Thedesign of the impeller plays a crucialrole in determining the performance of the pump.
   叶轮的设计对泵的性能起着至关重要的作用。