vacuum pump

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

此外，通过在打棉机上安装空泵，织物的水合作用时间得以。

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

ZJ罗茨空泵排大气，运行时需配备相应前级泵。