The definition of a dried out vacuum pump is a pump that will not use any Dry Vacuum Pump fluids to make a vacuum or contact the procedure gas and can also discharge to atmosphere. … Timing gears with oil reservoirs and close clearances between the rotors and housing are additional attributes that make up a dried out vacuum pump.
Principle of Operation
Dried out screw vacuum pumps operate with two screw rotors rotating in opposing directions. This traps the moderate to be pumped between the cylinder and the screw chambers and transports it to the gas discharge. … It also results in a lesser temperature load of the compressed gas.