This is of a dried out Dry Vacuum Pump vacuum pump is a pump that does not use any fluids to create a vacuum or contact the process gas and will also discharge to atmosphere. … Timing gears with essential oil reservoirs and close clearances between the rotors and housing are additional attributes that define a dried out vacuum pump.

Principle of Operation

Dry screw vacuum pumps operate with two screw rotors rotating in opposing directions. This traps the medium to end up being pumped between your cylinder and the screw chambers and transports it to the gas discharge. … It also results in a lesser temperature load of the compressed gas.