Rotary Pumps

What is a rotary pump?

Considered a positive displacement type that uses rotating mechanisms to move fluids or gases through piping systems. There are several types including gear pumps, screw pumps and vane pumps.

Unlike reciprocating pumps, which create a pulsing flow, rotary pumps are designed to generate a steady, unvarying flow. The main disadvantage is in order to work with maximum effectiveness, they need to have a very close clearance between the rotating mechanism and the walls of the pump chamber. Any wear and tear around the edges of the mechanism can greatly reduce pump performance.

How do they work?

The most basic types contain one or two rotating parts that are moving withing a non-concentric casing. The rotating parts create a vacuum in the suction, and move the liquid through the pump to the discharge. Some types, particularly screw pumps and rotary vane pumps, are a little more complicated than this, but the basic principles are the same. The turning mechanism simultaneously moves liquid through the outlet while drawing more liquid through the intake.

Where are they used?

Rotary pumps have a wide variety of applications, making up about 10 percent of all the pumps used in industry. They’re best for pumping clean and non-corrosive, non abrasive liquids, which makes them useful in oil transfer applications in the food industry.

Other related Pump Types include: piston pumps, lobe pumps, process pumps, chemical pumps.

Expert Advice

J. Hamilton Wright shows us some of the benefits that self-priming, centrifugal pumps can offer in industrial plants.

So now what do you do? As many of you know, this is a fairly common occurrence, particularly with pumps that have been around a long time. Here's some advice on what to do.

Learn how following the simple rule of NPSH Available > NPSH Required, can help you avoid cavitation.

Read All

Industry Updates

Switch to: Expert Advice | Pump Tweets

Sulzer Pumps says its acquisition of a privately-owned Spanish Pump Company will enhance its footprint in Europe. Sulzer announced its plans to buy Burgos, Spain-based Hidrotecar S.A. Friday.

KNF has introduced a new high-pressure, micro diaphragm pump which can dose or transfer liquids or liquid-gas mixtures at flow rates up to 300 ml/min.

Pump manufacturer Best PumpWorks recently announced its acquisition of the Shreveport, Louisana-based American Pump Technology, Inc.

Read All

Pump Tweets

WEF has awarded ITT Corporation's Water and Wastewater group the 2011 Innovative Technology Award. ITT Water & Wastewater - Flygt Products was awarded in the category of "collection systems", for Flygt's patented N-pump. The N-pump features a clog-resistant design and is equipped with the newly-designed Adaptive Impeller functionality.

KSB has purchased a majority stake in the Danish pump manufacturer Smedegaard. Smedegaard produces circulating pumps used in heating systems.

NETZSCH Mohnopumpen GmbH introduces a new version of its TORNADO rotary lobe pump. The new lobe pump is built to have a long service life and virtually eliminates any possibility of transmission damage due to leakage or contamination.

Read All