Impellers vs Propellers – What is the Difference?

Both are used to move fluids but have different shapes and perform different functions

photo of small boats in marina showing just the motors

In this “In The Mix” blog, we explore a topic that often causes confusion: What is the difference between impellers vs propellers?

This is a topic that may be best understood in boating terms. Gas-powered boats use both impeller and propellers. An impeller pulls water into the engine to cool it. Boats use a propeller to push the boat through the water.

So in simple terms, an impeller pulls while a propeller pushes. Read on to learn more about impellers vs propellers.

What is a propeller?

A boat engine uses an impeller and propeller. An impeller pulls water into the engine to help cool it. A propeller pushes the boat through the water.

A propeller is a type of fan that is used to move a fluid. They are often used in boats and other vehicles including submarines and aircraft. The propeller is connected to an engine that rotates it with enough force to move the vehicle itself.

The shape, number and angle of propeller blades depend on the type of vehicle using it. For example, an airplane propeller often has fewer blades than a boat propeller because it pushes air instead of water. Airplane blades are also angled downwards between 10-30 degrees depending on speed requirements.

What is an impeller?

An impeller is technically a type of propeller. However, it imparts a pulling, drawing or sucking force to fluids.

Impellers are used in a wide variety of applications including agitated tanks (as is the case for most ProQuip applications), pumps, washing machines and the aforementioned vehicles. For the latter, jet airplanes use a turbine impeller to pull air into the engine.

Impeller design varies based on the application. ProQuip tank agitators use turbine, gate, and anchor impeller designs to mix a wide variety of fluids (and sometimes small solids in a suspension) from chemicals to personal care products like body wash and toothpaste. Download our impeller white paper for more information on each impeller type we manufacture that might fit your application.

Photo of ProQuip-HiFlow-Impeller

The ProQuip HiFlow High Efficiency, Low Sheer Impeller is designed for low viscosity mixing applications.

How are impellers and propellers similar?

Impellers and propellers are fairly similar. Both use rotational energy to move fluid (but in different directions). Other similarities include the following:

  • An external motor powers them
  • Bernoulli’s principle (which relates fluid pressure to its speed) applies to the operation of both. When the speed of a fluid increases, the pressure decreases, and vice versa (

For More Information

For more information on ProQuip mixing solutions, email  or call us at 330-468-1850.

Sources: GlobalSpec