Q-VAC Automatic Priming Systems

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CFP's Website for Q-VAC High Quality Vacuum Priming Systems.
Call (800) 521-2083 (USA only) or contact us for assistance.

Liquid Ring Technology in Vacuum Priming Systems

Liquid Ring Vacuum Pump 


– –5 acfm to 145 acfm typical (¾ HP to 10 HP)
–Vacuum to 29” HgV (25 Torr)
–MUCH larger sizes available (250+ HP)
–316ss impellers and Viton mechanical seals standard
–All 316ss wetted parts and Teflon mechanical seals available
–Most robust technology available
–No metal-to-metal contact
–Only one moving part
–Almost no maintenance
–Unaffected by some ingestion of water and small/soft solids
–Requires a suitable seal water supply
–Performance is affected by seal water temperature


In a cylindrical housing, partially filled with sealing liquid, a multi-blade impeller on a shaft is positioned eccentrically.  Port plates with inlet and discharge openings are positioned on either side of the impeller.

A liquid ring is created by the centrifugal force generated by the rotating impeller.  This force holds the liquid ring against the inner wall of the pumping chamber. 

Since the impeller is located eccentric to the pumping chamber, the depth of the blades into the liquid ring decreases and increases as the impeller rotates.  This creates increasing impeller cell volume on the inlet port side, creating a vacuum.

On the discharge port side, the impeller cell volume decreases, as the blades move further into the liquid ring, increasing the pressure, until discharge takes place through the discharge port.  A continuous flow of fresh sealing liquid is supplied to the pump via the sealing liquid inlet.

We offer the best value in quality automatic vacuum priming systems for centrifugal water pump priming, siphon control systems, and water box primers.  Q-VAC Priming Systems are ideal for power plants, municipal water systems and wastewater treatment plants, industrial applications, irrigation systems, steel mills, and marine applications.  Please contact us for expert assistance in selecting the best solution for your application.

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