循环水泵可分为拥有叶片角度调节装置的可调叶片式，和叶片不可调节的固定叶片式。

The pump having the Angle adjustable vane is called the variable pitch vane type, and having the non-adjustable vane is called the fixed vane type.

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循环水泵可分为拥有叶片角度调节装置的可调叶片式，和叶片不可调节的固定叶片式。

The pump having the Angle adjustable vane is called the variable pitch vane type, and having the non-adjustable vane is called the fixed vane type.

youdao