Lubrication of Rotary High Vacuum Pumps Available to Purchase

Rotary high‐vacuum pumps are oil‐lubricated. The lubricating oil acts as a seal against atmospheric pressure, and to enable it to do this the pump is normally submerged, or virtually submerged, in the oil. In the course of operation of the pump, the oil inevitably becomes contaminated with substances extracted from the system under evacuation. This complicates the questions involved in selection of the oil and has given rise to a number of remarkable devices to limit the accretion of contaminants.