The rotor part is composed of shaft, middle wheel and balancing drum etc.

转子部分由轴、中轮、平衡鼓等组成。

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The axial gap of the balancing drum and a cross channel is a cone-shaped structure with a small entrance and large exit and can prevent from being obstructed by sand flowing through the gap;

平衡鼓和交叉流道的轴向间隙为入口小、出口大的锥形 结构，防止被流经间隙的砂子阻塞；

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