Impeller Pumps Key Terms

Learn the language of impeller pumps to make the right choices for your business

By Jess Buskirk

Impeller pumps are used for a wide variety of applications, from pumping sewage to making wine. In order to find the impeller pump that's right for your needs, it's important to learn some of the commonly used impeller pumps key terms. Read through the following key terms to gain a greater understanding of how impeller pumps move liquids and semi-liquids. When it's time to order a new pump, you'll know the meaning behind the product descriptions.

Positive displacement

Impeller pumps fall under the category of positive displacement pumps. Positive displacement works by creating a vacuum between two cavities to move liquids. As the liquid leaves one cavity, the vacuum effect draws in more liquid.
Try: Learn more about positive displacement pumps at The Engineering ToolBox. Additional information about positive displacement pumps can be found at the Rensselaer Polytechnic Institute website.

Sludge

Impeller pumps are known for their ability to handle sludge in wastewater applications. Sludge is the material or precipitate that accumulates in sewage.
Try: Read through the frequently asked questions about sludge at the Northumberland Association for Progressive Stewardship website. To learn how impeller pumps tackle sludge, visit WaterandWastewater.com.

Diffusers

Diffusers surround the impeller in a pump. These stationary vanes increase the efficiency of the pump by creating a gradually expanding area as liquid leaves the impeller.
Try: To see a diagram of diffusers in action, visit Engineer's Edge. Learn more about how diffusers work by visiting the Belzona website.

Single-suction and double-suction

Impeller pumps are designed as either single-suction or double-suction. A single-suction pump allows liquid to enter the impeller from one direction, while a double-suction pump draws in water from two directions.
Try: Read more about single-suction and double-suction impeller pumps at the McNally Institute.

Self-priming

Some impeller pumps are self-priming, meaning they are capable of reaching an optimum priming condition with only a combination of air and liquid. In order for a self-priming pump to work correctly, the casing must be submerged in liquid before turning on the pump. A self-priming pump removes the air from an air-liquid mixture, only moving the liquid.
Try: Learn more about self-priming pumps at PumpStoreUSA.com. For an example of a self-priming impeller pump, visit Go2marine.

Impeller features and types

When purchasing an impeller pump, it's important to understand the difference between an impeller feature and an impeller type. The features of an impeller make the pump more efficient for your application. For example, anti-static and corrosion resistant are features. The type of impeller is dependent on the application. Examples of impeller types include an axial flow propeller and a screw centrifugal.
Try: Browse through the various impeller features and types at GlobalSpec.