How pump specs can affect your filtration demands

Whether you need one for your house or business, it's important to consider pump specifications when choosing a filtration pump. From the size of the pump inlet and pump outlet to the flow rate and differential pressure, there's a lot to consider.

A centrifugal pump.
A centrifugal pump.

It's also important to understand that there are different types of pumps made for various industries and applications. Choosing the wrong pump and system components could result in ineffective or inefficient filtration and purification. In addition to the filters themselves, pumps play a crucial role in the filtration process. Therefore, it is essential to thoroughly check and understand the pump specifications when making your selection.

If you don't know the first thing about pumps and their role in purification, you've come to the right place. This article will look at how pump specifications affect your filtration needs and how to choose the right pump. We'll also look at how to understand pump specifications and how they relate to different types of pumps.


Understanding pump specifications

Pump specifications refer to the set of criteria that go into selecting a pump for your filtration needs. There are many different types of pumps used to filter and transport different types of liquids, and they're not all compatible with one another. Pump specifications include things like:

  • The size of the piping within the system
  • The type of liquid
  • The viscosity of the liquid
  • The available power source electric/air
  • The required flow and pressure needed to account for filter efficiency requirements
  • The flow rate and pressure drop
  • Material compatibility with the fluid
  • Temperature: ensure that the pump is suitable for the temperature range of the fluid.

It's important to consider each one of these specifications when deciding what type and size of pump you need.


Different types of pumps

In addition to the various pump specifications, there are many different types of pumps to choose from.

Centrifugal pumps

Centrifugal pumps are the most common type of pump used in water supply and filtration. Operating on the principle of centrifugal force, these pumps utilize a spinning impeller to impart kinetic energy to the fluid, causing it to move radially outward. The rotating impeller creates a low-pressure zone at the center, inducing suction and drawing fluid into the pump. As the fluid gains momentum, it is then propelled through the pump's discharge outlet. One notable feature of centrifugal pumps is their ability to handle large volumes of liquid at relatively low pressures.

Diaphragm pumps

Diaphragm pumps operate on the principle of positive displacement. These pumps utilize a flexible diaphragm to create a pulsating action, drawing and expelling fluid through a series of check valves. What sets diaphragm pumps apart is their ability to handle a wide range of fluids, including abrasive and viscous substances, without compromising efficiency.

Graco electric diaphragm pump. -

Peristaltic pumps

Peristaltic pumps, also known as tube or hose pumps, operate by compressing and relaxing a flexible tube with a rotating roller or shoe. This action creates a seal, pushing fluid through the tube and out of the pump. This design eliminates contamination risks, as the fluid remains entirely within the tubing, making it ideal for applications in pharmaceuticals, biotechnology, and food processing, where accuracy, sterility, and minimal maintenance are vital for fluid transfer processes.

Metering pumps

Metering pumps have finely tuned flow rates because they pump small amounts of liquids periodically.

In addition to these pumps, there are also drum pumps, hand-operated pumps, and gear-driven pumps. It's important to understand how each of these pumps works so that you can choose the right one.


Aspects to consider when choosing a pump

To help you decide which type of pump you need, here's a list of things to consider.

Corrosion resistance

All water, especially your city or well water, has some level of acidity and corrosive materials in it. Therefore, it's important to choose a corrosion-resistant pump with the appropriate materials of construction including elastomers such as O-rings and seals unless you plan to replace it every couple of years.


Durability is a critical consideration in pump selection, and centrifugal pumps stand out as one of the most robust and corrosion-resistant options available. With various pumps designed for specific applications, it's crucial to ensure the right fit for your needs. If you're uncertain, don't hesitate to reach out to your local Harrington specialist for guidance.

Filtration type

What type of liquid you plan to pump and filter is extremely important when choosing your pump. Some types of pumps are meant to handle liquids with higher viscosity or that contain solids, while others are intended for water.


As with all things, your budget will play a role when selecting your pump. While you want a high-quality pump that will get the job done, you also don't want to blow your entire budget on it.

Size of the application

The size of your application will play a significant role in pump selection. Certain types of pumps are better equipped for smaller application, while others are good for larger ones.

Pump environment

Finally, how and where you install your pump will affect the type of pump you need. Some pumps have a more durable and rugged exterior than others, and a brutal environment, such as the outdoors, won't affect their operating efficiency.


Things to consider when choosing your pump size

Once you know what type of pump you need, you'll want to choose one that's the right size.

Differential pressure

Differential pressure in the context of pumps refers to the variance in pressure between the pump's inlet and outlet. It is a critical parameter used to assess the performance and efficiency of a pump system. It's essential to understand what the differential is so that your pump doesn't increase or decrease the pressure too much. Understanding and controlling differential pressure is crucial for optimizing pump performance, ensuring system reliability, and promoting energy efficiency in fluid transport applications.

Fluid temperature

The temperature of the fluid being pumped can influence the material compatibility of pump components, affecting their durability and resistance to corrosion. Additionally, temperature variations can alter fluid viscosity, potentially impacting the pump’s efficiency and flow rates. Choosing a pump designed to operate within the specified temperature range ensures optimal performance, prevents issues like cavitation or seal failure, and contributes to the overall reliability and safety of the fluid transfer system.


Viscosity refers to how thick or thin fluid is. Fluids with high viscosity are more resistant to flow than fluid with low viscosity. As such, a more viscous fluid will require a larger pump that pumps at higher pressure than a pump handling liquids with low viscosity. If you're simply pumping water, however, viscosity shouldn't be much of a factor.

Flow rate

For most applications, flow rate is the most important factor when it comes to pump size. Flow rate refers to how many gallons per minute of fluid a pump can move in a given amount of time. The higher the flow rate is, the more fluid your pump can move. It's important to consult the pump experts at Harrington to know what flow rate is right for your application and filtration system.


Last but not least, fluid density is an important factor to consider when it comes to pump size. Fluid density refers to how much a liquid weighs and often goes hand in hand with viscosity. The more viscous a liquid is, the denser it will be and the bigger your pump needs to be.

Here is a quick reference for questions that you should be prepared to answer when considering a pump. The pump specialists at Harrington will always ask for your STAMP (Size, Temperature, Application, Media, and Pressure). It is essential that these questions are addressed to select the appropriate pump for your application.


About the author

Kevin Maple is the director of Marketing at Harrington Process Solutions, a North American distributor and supplier of industrial process products and solutions. Maple has been a critical part of the Harrington team for more than a quarter of a century, providing marketing strategy within the industrial sector. He has in-depth knowledge and understanding of piping, fluid handling, instrumentation and high-purity applications.