Common Vacuum Terminology 3

  1. ranges of vacuum:The vacuum region is roughly divided as follows:

                      Pa        Torr

Low vacuum:            105~102         760~1
Medium vacuum:          102~10-1        1~10-3

High vacuum:            10-1~10-5       10-3~10-7

Ultra-high vacuum:       <10-5           <10-7

  1. gas:Substances that are free to occupy any space and are not subject to intermolecular interactions. Note: In vacuum technology, the term "gas" is not strictly applied to non-condensable gases and steam.
  2. n,m-3 number density of molecules:At a given instant, theChina PVD Plating Machine Suppliers number of molecules in the volume around a point in the gas is divided by that volume.
  3. ι、λ,m mean free path:The distance that a molecule travels with other gaseous molecules every two consecutive collisions is called free path. The average of quite a number of different free paths is called the average free path.

Contact us today


No. 81 West Jinniu Road, Yuyao,
Ningbo City, Zhejiang Provice, China