The Armstrong Positive Displacement Liquid Ring Vacuum Pump has one moving part, a balanced rotor keyed on a shaft. The rotor has a series of blades like a paddle wheel on an old riverboat. The rotor is installed offset and supported by two (2) grease-lubricated bearings mounted outside the pumping area, which allows no metal-to-metal contact. The casing (body), is partially filled with seal liquid (normally water). When the shaft is rotated, the

rotor turns forcing the seal liquid to form a ring inside the casing ( body) and with the rotor eccentric to the center of the casing (body), a liquid piston is formed in each rotor chamber. This piston moves in and out from the hub of the rotor, When this piston moves out from the hub it creates a vacuum behind it pulling gas (normally air) in from the inlet prot. As the piston moves towards the hub of the rotor the gas that had been trapped in the vacuum stroke is now pushed out through the discharge port along with a percentage of seal liquid used in the cooling of the pump.