oil diffusion pump

Older instruments may have used oil diffusion pumps for high vacuum regions.

The oil diffusion pump is operated with an oil of low vapor pressure.

While vacuum pumps are of many kinds, oil diffusion pumps in combination with a fore pump are amongst those most popular.

A classic foreline is a hose or tube that connects a rotary vane pump to the outlet of an oil diffusion pump, although vacuum technology now uses a vast array of roughing pumps and high vacuum pumps.

Due to backstreaming, oil diffusion pumps are not suitable for use with highly sensitive analytical equipment or other applications which require an extremely clean vacuum environment, but mercury diffusion pumps may be in the case of ultra high vacuum chambers used for mercury deposition.