Screw pump is a kind of rotary pump, when the outlet end is blocked, the pressure will gradually increase, so that more than a predetermined pressure value.

螺杆泵是一种容积式回转泵，当出口端受阻以后，压力会逐渐升高，以至于超过预定的压力值。

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The idea is with the help of vacuum pump to increase the pressure difference between material hopper and vacuum chamber, hence the packing environment can be achieved.

通过真空泵减压，使真空室里面的负压慢慢增大，在产品供应漏斗和真空室之间产生压差，从而实现包装过程。

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The top plug has a solid body that provides positive indication of contact with the landing collar and bottom plug through an increase in pump pressure.

顶塞具有一个实心的塞体，根据泵压的增加它能可靠地显示与止塞箍和底塞的接触。

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However, with the pump shut down a pressure increase was seen in the standpipe (SPP).

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