The Complete Guide to Peristaltic Pumps: How They Work

1. What Is a Peristaltic Pump?

A peristaltic pump is a type of positive displacement pump that moves fluid by compressing a flexible hose or tube with rotating rollers. The pumped fluid never contacts any internal pump components other than the hose itself, making peristaltic pumps ideal for applications where contamination must be avoided or where the fluid being pumped is abrasive, corrosive, or shear-sensitive.

Peristaltic pumps are also commonly referred to as hose pumps (when using industrial-grade reinforced hoses) or tube pumps (when using smaller-diameter tubing, typically in laboratory or medical applications). The distinction matters: hose pumps are built for heavy industrial duty with flow rates reaching tens of thousands of gallons per hour, while tube pumps are designed for precision low-flow applications in laboratories and medical devices.

The concept of peristaltic pumping dates back to 1855, when the French engineer and physician Eugène de Poitiers first described the mechanism of using external compression on a flexible conduit to move fluid. The name itself comes from peristalsis — the involuntary muscular contractions that move food through the human digestive system. Just as your esophagus squeezes food downward in a wave-like motion, a peristaltic pump squeezes fluid through a hose using rotating rollers.

Modern industrial peristaltic pumps emerged in the mid-twentieth century as advances in synthetic rubber and hose manufacturing made it possible to build hoses that could withstand thousands of hours of continuous compression and release cycles. Today, companies like Ragazzini in Italy (whose Rotho line KECO distributes across North America) manufacture peristaltic pumps that handle everything from precise chemical dosing at fractions of a gallon per hour to massive slurry transfer operations exceeding 47,000 gallons per hour.

What sets peristaltic pumps apart from centrifugal pumps, progressive cavity pumps, diaphragm pumps, and other positive displacement technologies is their fundamental simplicity: the only wear part is the hose. There are no seals to leak, no valves to clog, no impellers to corrode, and no glands to pack. This single-wear-part design translates directly into lower maintenance costs, higher uptime, and simpler operation — advantages that have made peristaltic pumps the preferred choice across dozens of industries worldwide.

2. How Peristaltic Pumps Work

The operating principle of a peristaltic pump is elegantly simple. Inside a circular pump housing, a set of two or three rollers is mounted on a rotating assembly called the rotor. A flexible hose is installed around the inside circumference of the housing, forming a U-shape or crescent between the suction port and the discharge port.

As the rotor turns, the rollers press against the hose and compress it flat against the inner wall of the housing. This compression creates a sealed pocket of fluid ahead of the roller. As the roller continues its rotation, it pushes this pocket of fluid forward toward the discharge port. Behind the roller, the hose springs back to its original round shape, creating a vacuum that draws new fluid in through the suction port.

This continuous cycle of compression, displacement, and recovery produces a smooth, steady flow of fluid. The action is identical to what happens when you squeeze a toothpaste tube from the bottom — the contents move forward ahead of the compression point. In a peristaltic pump, this happens continuously as the rollers orbit around the hose.

Self-priming capability is one of the most valuable characteristics of peristaltic pumps. When the rollers lift off the compressed hose, the hose elastically recovers to its original shape. This recovery creates a strong vacuum on the suction side — strong enough to lift fluid up to 29.5 feet (9 meters) of suction head. This means peristaltic pumps can be installed above the fluid source and will reliably draw fluid up to themselves without needing to be primed or flooded first.

Bi-directional operation is another inherent advantage. Because the pump mechanism relies purely on roller rotation, simply reversing the direction of the motor reverses the flow direction. There are no check valves or directional components to change. This makes peristaltic pumps exceptionally useful in applications where fluid needs to be moved in both directions — such as filling and emptying tanks, or performing clean-in-place (CIP) procedures.

The flow rate of a peristaltic pump is determined by three factors: the internal diameter of the hose, the number of rollers, and the rotational speed of the rotor. Because each roller revolution displaces a fixed volume of fluid, peristaltic pumps deliver highly accurate and repeatable flow rates. This volumetric accuracy typically falls within plus or minus one percent, making peristaltic pumps excellent for metering and dosing applications where precise quantities matter.

Unlike centrifugal pumps, where flow rate varies significantly with changes in discharge pressure (the pump curve), peristaltic pumps maintain a nearly constant flow rate regardless of pressure changes. This is because the positive displacement mechanism physically pushes a fixed volume with each revolution. Higher discharge pressures do slightly reduce output due to hose compression, but the effect is far less pronounced than in non-positive displacement pump types.

3. Key Advantages of Peristaltic Pumps

Peristaltic pumps offer a combination of advantages that no other pump technology can match. Understanding these benefits helps explain why peristaltic pumps have become the standard in applications ranging from chemical processing to food production.

Dry-Run Capable

Peristaltic pumps can run dry indefinitely without damage. Because there are no internal seals, bearings, or close-tolerance components that require lubrication from the pumped fluid, running a peristaltic pump without fluid simply means the rollers compress an empty hose. This is a critical advantage in applications where the fluid supply may be intermittent or where the pump must start before the fluid source is connected. By contrast, running a centrifugal pump or progressive cavity pump dry for even a few minutes can cause catastrophic seal failure and bearing damage.

Self-Priming

As described above, peristaltic pumps generate a strong vacuum on the suction side, capable of self-priming up to 29.5 feet (9 meters) of suction lift. This eliminates the need for foot valves, priming systems, or flooded suction arrangements. The pump can be installed at a convenient location above the fluid source and will reliably draw fluid up to itself.

Handles High-Viscosity Fluids and Slurries

Peristaltic pumps excel at moving thick, viscous materials and heavy slurries that would clog or damage other pump types. Because the fluid passes through a smooth, open hose bore with no restrictions, constrictions, or tight clearances, materials with up to 80% solids content can be pumped without difficulty. This makes peristaltic pumps the go-to choice for mining slurries, ceramic glazes, concrete admixtures, and thick food products like peanut butter or tomato paste.

Gentle Pumping Action

The low-shear pumping action of peristaltic pumps preserves the integrity of shear-sensitive materials. There are no impellers, vanes, or close-tolerance components that would damage delicate products. This matters enormously in food and beverage applications (where breaking down fruit pieces or emulsions degrades product quality), pharmaceutical manufacturing (where shear can denature proteins), and wastewater treatment (where preserving floc structure improves settling performance).

No Contamination Risk

Because the pumped fluid only contacts the inside of the hose, there is zero risk of contamination from pump components. No seals, no lubricants, no packing materials, and no metallic components touch the fluid. This makes peristaltic pumps inherently suitable for food-grade, pharmaceutical, and sterile applications. Changing the hose material is all that is needed to meet different chemical compatibility or regulatory requirements.

Reversible Flow

Reversing the motor direction instantly reverses the flow direction. No valves need to be changed, no piping needs to be reconfigured, and no mechanical modifications are required. This simplifies system design for applications that require bi-directional flow, such as tank filling and emptying, filter backwashing, and cleaning procedures.

Built-In Leak Detection

Industrial peristaltic pumps like the Rotho line feature a sealed pump housing that acts as a secondary containment vessel. If a hose fails during operation, the pumped fluid is captured inside the pump housing rather than spilling onto the floor or into the environment. Many industrial peristaltic pumps include leak detection sensors that automatically shut down the pump when a hose failure is detected, preventing product loss and environmental contamination.

Low Maintenance

With only one wear part — the hose — maintenance on a peristaltic pump is straightforward and predictable. There are no mechanical seals to replace, no packing to adjust, no valves to rebuild, and no impellers to resurface. When the hose reaches the end of its service life, it is simply replaced — a procedure that typically takes less than 30 minutes on modern quick-change designs. This predictable maintenance schedule makes it easy to plan downtime and keep spare parts inventory to a minimum.

4. Roller vs Shoe Design: Why It Matters

Not all peristaltic pumps are created equal. The two primary mechanical designs used in industrial peristaltic pumps are the roller design and the shoe design. The choice between these two approaches has significant implications for hose life, energy efficiency, heat generation, and overall operating costs.

Roller Design (Used by Ragazzini Rotho)

In a roller-type peristaltic pump, the compression elements are free-spinning rollers mounted on bearings. As the rotor turns, the rollers roll along the surface of the hose rather than sliding across it. This rolling contact dramatically reduces friction between the compression element and the hose surface.

The benefits of roller design are substantial. Lower friction means less heat generation during operation, which directly extends hose life because heat is the primary enemy of rubber and elastomer durability. Less friction also means lower energy consumption — the motor does not have to overcome the sliding friction that shoe-type pumps create. Ragazzini Rotho pumps use this roller-bearing design across their entire product range, from the compact S Series to the heavy-duty LD Series.

Shoe Design

In a shoe-type peristaltic pump, the compression elements are fixed shoes (also called slippers or pads) that slide across the surface of the hose as the rotor turns. Because the shoes do not rotate, there is continuous sliding friction between the shoe surface and the hose.

While shoe-type pumps have a simpler mechanical construction (no bearings in the compression elements), the trade-offs are significant. The sliding friction generates considerably more heat, which accelerates hose degradation and shortens hose life. Some shoe-type pumps require a glycerin or lubricant bath between the hose and housing to reduce this friction, adding complexity and an additional maintenance item. The higher friction also means higher power consumption for the same flow rate compared to a roller-type pump.

Why Roller Design Is Superior for Industrial Applications

For demanding industrial applications where pumps run continuously or for extended shifts, the roller design delivers clear advantages:

• Longer hose life: Lower friction and less heat mean the hose lasts significantly longer before replacement is needed
• Lower operating temperature: Reduced friction generates less heat, protecting both the hose and the pumped product from thermal degradation
• Higher energy efficiency: Less friction means the motor draws less power, reducing operating costs over the life of the pump
• No lubricant required: Roller-type pumps typically operate without a lubricant bath, eliminating a potential contamination source and maintenance item
• More consistent flow: The smooth rolling action produces less pulsation than the stick-slip motion of shoe-type pumps

These advantages compound over time. A pump that runs 8,000 hours per year with a roller design may achieve hose life of 8,000 to 10,000 hours, while the same application with a shoe design might require hose changes every 3,000 to 5,000 hours. The labor, materials, and downtime costs of more frequent hose changes can dwarf the initial price difference between pump types.

5. Applications by Industry

The unique characteristics of peristaltic pumps — contamination-free pumping, solids handling, dry-run capability, and gentle action — make them the preferred choice across a wide range of industries. Here is how peristaltic pumps are used in the most common industrial applications.

Chemical Dosing and Processing

Peristaltic pumps are widely used for precise metering of acids, bases, polymers, flocculants, and other chemicals. Their volumetric accuracy (typically plus or minus one percent) makes them ideal for dosing applications where exact quantities are critical. Because the chemical only contacts the hose, choosing the right hose material (such as EPDM for acids and bases, or Hypalon for oxidizing chemicals) provides complete chemical compatibility without expensive exotic alloy pump components. The self-priming capability allows pumps to draw chemicals directly from storage drums or totes without the need for elevated supply tanks. Learn more about chemical dosing applications.

Mining and Mineral Processing

In mining operations, peristaltic pumps handle some of the most demanding fluids imaginable: abrasive ore slurries, mine tailings, thickener underflow, and flotation concentrates with solids concentrations exceeding 50%. Unlike centrifugal pumps that suffer rapid impeller erosion from abrasive particles, peristaltic pumps pass these materials through a smooth, open hose bore where the abrasive particles simply flow through without causing wear to the pump mechanism. The hose absorbs the abrasion and is replaced on a predictable schedule. Many mining operations have switched to peristaltic pumps specifically because the cost of frequent centrifugal pump rebuilds exceeds the cost of periodic hose replacement. Explore mining and aggregate applications.

Food and Beverage

The food industry relies on peristaltic pumps for transferring chocolate, yogurt, fruit pulps, wine must, sauces, cream, yeast slurries, and other food products. The gentle, low-shear pumping action preserves product texture and quality — whole fruit pieces pass through undamaged, emulsions remain stable, and live cultures in yogurt and fermented products survive intact. Food-grade silicone and FDA-compliant hose materials ensure regulatory compliance, and the fact that only the hose contacts the product simplifies cleaning validation. Many food plants use the reversible flow capability for clean-in-place procedures, running cleaning solution backward through the pump to flush all surfaces. See food and beverage applications.

Water and Wastewater Treatment

Municipal and industrial water treatment plants use peristaltic pumps for sludge transfer, lime slurry dosing, activated carbon injection, polymer dosing, and filtration system supply. Sludge and lime slurry are particularly challenging for conventional pumps — sludge contains rags, grit, and fibrous material that clogs impellers and destroys mechanical seals, while lime builds up inside pump cavities and valves. Peristaltic pumps handle both without difficulty because the open hose bore passes solids and the continuous compression action prevents lime buildup. Discover water treatment solutions.

Pharmaceutical Manufacturing

Pharmaceutical applications demand sterile, contamination-free fluid transfer with full traceability and validation capability. Peristaltic pumps meet these requirements because the pumped product only contacts the hose, which can be supplied with full material certifications, batch traceability, and sterilization documentation. The absence of seals eliminates a common source of microbial contamination in pharmaceutical pump systems. Single-use hose installations are also practical for batch processing, where the hose is replaced between batches to prevent cross-contamination. Read about pharmaceutical pump applications.

Ceramics and Tile Manufacturing

Ceramic manufacturers use peristaltic pumps to transfer glazes, slips, engobes, and abrasive ceramic slurries. These materials are notoriously difficult to pump — they are abrasive enough to destroy centrifugal pump impellers in weeks, and their tendency to settle and solidify makes them problematic for diaphragm and progressive cavity pumps. Peristaltic pumps handle these materials reliably because the smooth hose bore passes abrasive particles without wear to the pump mechanism. Major European tile manufacturers including Cerdomus and Graniti Fiandre rely on Ragazzini Rotho peristaltic pumps for their production lines. Explore ceramics applications.

6. Selecting the Right Peristaltic Pump

Choosing the correct peristaltic pump for your application requires evaluating several key parameters. Getting these right ensures optimal performance, maximum hose life, and the lowest total cost of ownership.

Flow Rate Requirements

The first parameter to define is the required flow rate — both the normal operating flow and any peak or surge flow requirements. The Ragazzini Rotho pump range covers an extraordinarily broad spectrum of flow rates across four series:

• S Series (Small): 0.10 to 660 GPH — precision dosing and laboratory applications
• M Series (Medium): 26 to 5,280 GPH — general industrial transfer and dosing
• L Series (Large): 660 to 31,700 GPH — high-volume industrial transfer
• LD Series (Large Duty): 660 to 47,750 GPH — maximum flow and pressure applications

Flow rate in a peristaltic pump is adjusted by changing the motor speed, typically through a variable frequency drive (VFD). The Keco Drive package integrates the motor, gearbox, and VFD into a single unit, simplifying installation and providing precise speed control from the factory.

Discharge Pressure

Determine the total discharge pressure required for your system, including static head, friction losses, and any back pressure from downstream equipment. Rotho pumps are available with discharge pressure ratings up to 290 PSI (LD Series), with lower-pressure models available where high pressure is not needed. Specifying only as much pressure capability as you need helps optimize hose life, since higher-pressure operation increases the compression forces on the hose.

Fluid Characteristics

Understanding your fluid is essential for proper pump and hose selection:

• Viscosity: Peristaltic pumps handle fluids from water-thin liquids to extremely viscous pastes. Higher viscosity fluids may require larger hose diameters or slower pump speeds to achieve optimal flow.
• Solids content: Define the percentage of solids, the particle size, and the hardness of the solids. Peristaltic pumps handle up to 80% solids content, but hose material selection may vary based on the abrasiveness of the particles.
• Temperature: Standard hose materials operate from -4 to 176 degrees Fahrenheit (-20 to 80 degrees Celsius). Specialized materials extend this range for extreme applications.
• Chemical compatibility: Match the hose material to the chemical composition of the fluid to ensure long hose life and prevent degradation.

Hose Material Selection

Selecting the right hose material is critical for maximizing performance and hose life. The most common industrial hose materials include:

• Natural Rubber (NR): Excellent abrasion resistance, good for slurries, mining, and general industrial use
• Nitrile Rubber (NBR): Good oil and fuel resistance, used for petroleum-based fluids
• EPDM: Superior chemical resistance to acids, bases, and polar solvents; standard for chemical dosing
• Hypalon (CSM): Excellent resistance to oxidizing chemicals, ozone, and weathering
• Silicone: FDA-compliant, excellent for food, beverage, and pharmaceutical applications; wide temperature range

KECO's engineering team can help match the right hose material to your specific fluid chemistry and operating conditions. Use our pump selector tool for an initial recommendation, or contact us for a detailed application review.

7. Maintenance and Hose Life

One of the most compelling advantages of peristaltic pumps is their minimal maintenance requirements. With only one wear part — the hose — maintenance planning is straightforward and costs are predictable.

Typical hose life ranges from 2,000 to 10,000+ hours depending on the application conditions. Factors that influence hose life include the pump speed (slower is better for hose longevity), discharge pressure (lower pressure extends life), fluid characteristics (abrasive or hot fluids reduce life), and the hose material selected. In favorable conditions — moderate speeds, low pressure, non-abrasive fluids — hose life exceeding 10,000 hours is achievable.

Ragazzini Rotho pumps feature a quick-change modular hose system that allows hose replacement without special tools or extensive pump disassembly. A trained technician can complete a hose change in under 30 minutes, minimizing downtime. The modular design also means that hoses can be pre-staged as spare parts and swapped in quickly when needed.

Beyond hose replacement, no other routine maintenance is required. There are no mechanical seals to replace, no packing to adjust, no valves to rebuild, no bearings to grease (the roller bearings are sealed for life), and no impellers to inspect. This zero-maintenance characteristic is a major factor in the total cost of ownership calculation, particularly when compared to progressive cavity pumps (which require stator replacement and rotor inspection) or centrifugal pumps (which require seal replacement, impeller inspection, and bearing maintenance).

For more information on maintenance procedures and hose ordering, visit our support page or contact our service team.