Positive pressure air is usually provided by air compressor and negative pressure air is usually provided by vacuum air pump .

正压力空气一般由空压机提供，负压力空气一般由 真空 泵提供。

Strong self-suction pump is a kind of mechanical self-suction pump with unique vacuum unit . It can discharge completely air of suction side making running conditions for the pump .

强自吸泵为机械式自吸泵，具有独特的吸 真空装置，可将 泵的吸入侧 空气排净，达到 泵正常运转的条件。

Feasibility Study on Transformation of Vacuum Water Jet Air Ejector into Water Ring Vacuum Pump for Medium and Small Power Generating Set

中小型机组 真空系统 射水抽 气器改造为水环式真空 泵的可行性研究

So it is necessary to provide both the air compressor and vacuum air pump on the occasion of both positive pressure air and negative pressure air needed by some pneumatic driving devices .

对于那些既需要正压力空气又需要负压力空气的气动系统，工作时必须同时配备空压机和 真空 泵两种 空气动力源。

After comparing the performance features of the water jet air ejector water ring vacuum pump and steam jet air ejector the water ring vacuum pump was chosen with satisfactory effect .

比较 射水抽气器、水环 真空泵和射汽抽 气器的性能特点后，确定选用水环真空 泵，取得满意的效果。

Some Problems happened in the vacuum system during the commissioning have been described in the paper such as the exhaust hinder of vacuum pump air leakage of condenser and pump turbine block of inlet filter of vacuum pump and too high water level of condenser etc.

该文介绍了600MW 汽轮机在试 运时，真空系统出现的 真空泵排气受阻、凝汽器 进 空气、小汽机轴封漏 空气、真空泵入口滤网堵塞、凝汽器水位过高等问题。