Measurement Methods for Micro Pumping Speed of Vacuum Pump: A Review Study

The latest development of the measurement methodology of micro pumping speed for vacuum pumps was tentatively reviewed.Firstly,the operation principles,strengths and weaknesses of the commonly used techniques reported in literature,including the flow meter method,static volume method and dynamic flow method,were discussed with specific application examples.Next,the limitations,difficulties,problems and solutions of these measurement methods were analyzed.And finally,suggestions on selection of the measurement methods in specific realistic situations,were made. In addition,the development trends,in theoretical and experimental studies of micro pumping-speed evaluation methodology,were also briefly discussed.To be specific,when it comes to micro-pumping speed measurement,two interesting subjects were proposed: one is how to exactly determine the lower limit(< 10^-5 m³/s),and the other is how to deal with gases other than H₂ and N₂,such as gas-mixtures and nobles.