真空泵

Further mose, by installing vacuum pump on scutcher, hydration of time with fabric expanding.

，过在打棉机上安装真空泵，织物的水合作用时间得以延长。

ZJ type Roots vacuum pump can't discharge gases directly into the air,it should be equipped with a cowesponding prepump at operation.

ZJ型罗茨真空泵不能直排大气，运行时配备相应前级泵。