Positive Displacement Pumps

Our Positive Displacement Pump Products:

Here are just a few of the positive displacement  pumps that we offer:

What Are Positive Displacement Pumps?

Positive displacement pumps are designed to move a fixed amount of fluid with each cycle, creating a consistent and controlled flow regardless of system pressure changes.

Unlike centrifugal pumps, which rely heavily on velocity and pressure changes, positive displacement pumps focus on moving the fluid itself. This makes them ideal for applications involving thicker liquids, high-viscosity products, abrasive materials, and systems that require accurate flow control.

These pumps are especially useful when fluids should not separate, foam, or shear during transfer. They also perform well in high-pressure environments where consistent output is critical.

This makes them a strong choice for industries handling chemicals, oils, slurries, wastewater, adhesives, food products, and other demanding materials.

Common Applications for Positive Displacement Pumps

Positive displacement pumps are used across a wide range of industrial operations because they perform well in conditions where standard pumps often struggle.

Wastewater facilities use them for sludge transfer and chemical dosing. Chemical plants depend on them for controlled movement of aggressive or sensitive fluids. Asphalt operations rely on them for thicker materials that require steady flow without interruption.

Marine fueling systems, food processing plants, mining operations, and manufacturing facilities also benefit from these pump designs.

In many cases, the goal is not maximum speed. The goal is a controlled, dependable transfer that protects both the product and the equipment around it.

That is where positive displacement pumps perform best.

Diaphragm Pumps and AODD Pumps

Diaphragm pumps operate using flexible diaphragms and check valves to move fluid through the system. As one chamber opens, another closes, creating a steady pumping action.

These pumps are often used for chemical transfer, wastewater treatment, and abrasive materials because they can handle solids and harsh fluids without major damage.

Air-operated double diaphragm pumps, often called AODD pumps, are especially popular in industrial facilities because they offer strong durability and flexible installation options.

They are also a good fit for operations that need self-priming performance or dry-run capability without immediate damage to the system.

For facilities dealing with unpredictable fluid conditions, diaphragm pumps often provide strong reliability with manageable maintenance needs.

Gear Pumps and Rotary Vane Pumps

Gear pumps and rotary vane pumps use rotating internal components to move fluid from one point to another.

These systems are often selected for oils, lubricants, fuels, and other clean, consistent fluids where accurate flow and smooth transfer are important. They are commonly used in lubrication systems, fuel transfer operations, and industrial process lines.

Because these pumps rely on internal sealing surfaces, they usually require priming and should not run dry for extended periods.

When properly matched to the application, they provide excellent efficiency and dependable long-term performance.

For facilities managing lubricants, fuel oils, or other controlled fluids, rotary systems often provide excellent day-to-day consistency.

Reciprocating Pumps for High-Pressure Systems

Reciprocating pumps use pistons moving within sealed cylinders to create controlled fluid movement under high pressure.

These pumps are ideal when the system requires lower flow volume but significantly higher discharge pressure. Common applications include pressure washing systems, chemical injection, and industrial cleaning operations.

They are often selected when precision matters more than speed.

Because of the higher-pressure output, proper system design is critical. Valve protection, piping selection, and pressure monitoring all become important parts of long-term reliability.

When used correctly, reciprocating pumps deliver excellent control in demanding industrial environments.

Peristaltic Hose Pumps for Sensitive and Abrasive Fluids

Peristaltic hose pumps move fluid through flexible tubing using rollers or wipers that compress the hose and push material forward.

This design keeps the fluid contained within the hose itself, which helps prevent contamination and protects sensitive materials from outside exposure.

These pumps are often used for sludge, slurry, chemical dosing, and fluids containing solids or abrasive particles. Because the fluid does not contact the pump’s internal moving parts, maintenance can be simpler in certain applications.

Facilities handling aggressive or contamination-sensitive materials often choose peristaltic pumps for both safety and product protection.

Progressive Cavity Pumps for Thick Materials

Progressive cavity pumps, also called helical rotor pumps, use a corkscrew-shaped rotor to move fluid through sealed cavities.

This design creates smooth, steady movement even when handling thick, viscous, or shear-sensitive materials. Sludge, adhesives, food products, and chemical slurries are common examples.

These pumps perform especially well when product consistency must be preserved during transfer.

Because the sealed cavities separate fluid movement, the system can maintain strong efficiency under higher pressure without excessive turbulence.

For facilities working with challenging fluids, progressive cavity pumps are often one of the most reliable long-term solutions.

Eccentric Disc Pumps for Gentle Product Handling

Eccentric disc pumps combine characteristics of both peristaltic and centrifugal designs.

They use a rotating disc and a stationary disc to create gentle product movement while maintaining efficient flow. This makes them a strong option for fluids that need careful handling without excessive agitation.

These pumps are commonly used in food processing, pharmaceutical applications, and specialty chemical transfer where product integrity is important.

Their design also allows for easier cleaning and strong sanitary performance in operations where cleanliness is a top priority.

For facilities focused on both efficiency and product quality, eccentric disc pumps can be an excellent fit.

PSG West Coast Master Distributor Support

Northwest Pump is proud to serve as PSG’s West Coast Master Distributor for Abaque, Almatec, and Mouvex products.

This gives customers direct access to proven solutions across peristaltic hose pumps, diaphragm systems, and eccentric disc technologies backed by strong manufacturer support and expert local guidance.

When customers need help selecting the right Abaque, Almatec, or Mouvex system, they are not navigating the process alone. Our team helps evaluate the application, recommend the right configuration, and support long-term operation after installation.

That level of access creates faster answers and stronger confidence for industrial buyers.

Choosing the Right Positive Displacement Pump

The best pump is the one that matches the actual job.

Fluid viscosity, solids content, operating temperature, required pressure, suction conditions, and maintenance expectations all influence which design will perform best. Choosing based only on horsepower or price often leads to expensive downtime later.

This is where experience matters.

Northwest Pump helps customers review the full application before recommending a system. We look beyond the product brochure and focus on how the pump will perform in your real operating environment.

That leads to better reliability, easier maintenance, and stronger long-term value.

Frequently Asked Questions About Positive Displacement Pumps

How do I know if I need a positive displacement pump instead of a centrifugal pump?

If your system handles thick fluids, abrasive materials, sensitive products, or requires consistent flow under changing pressure, a positive displacement pump is often the better choice. Centrifugal pumps usually perform best with thinner, lower-viscosity fluids.

Can positive displacement pumps handle solids?

Yes, many types can. Diaphragm pumps, peristaltic pumps, and progressive cavity pumps are commonly used for fluids containing solids, sludge, slurry, and abrasive materials.

Are these pumps difficult to maintain?

Maintenance depends on the pump type and application. When properly selected and installed, many positive displacement pumps offer predictable service intervals and strong long-term reliability. Matching the right pump to the fluid is a major factor.

What industries use positive displacement pumps the most?

Wastewater treatment, chemical processing, food manufacturing, asphalt operations, mining, marine fueling, and industrial production facilities all commonly use these systems.

Can NW Pump help with replacements and upgrades for existing systems?

Yes. Many customers come to NW Pump for retrofit projects, system expansions, and pump replacements. We help evaluate the current setup and recommend practical upgrades that improve reliability without unnecessary overspending.

Let’s Talk About the Right Pump for Your Operation

Positive displacement pumps are not one-size-fits-all solutions. The right system depends on your process, your product, and your long-term operational goals.

Whether you are designing a new build, replacing aging equipment, or improving an existing industrial system, Northwest Pump helps you make informed decisions backed by real expertise.

Our team works with trusted manufacturers, proven technologies, and customers who need practical answers they can rely on.

If you are evaluating positive displacement pumps for your facility, talk with our team today to find the right fit for your operation.