Electric Diaphragm Pumps: An Overview

Learn about electric diaphragm pumps

What are Electric Diaphragm Pumps?

Electric diaphragm pumps, also known as sealless process pumps for specific designs, are used to transfer fluids efficiently and reliably. Depending on the technology, electric diaphragm pumps can transfer liquids with low, medium or high viscosities, as well as liquids with suspended solids. They also can handle many aggressive chemicals such as acids because they can be constructed with a wide variety body materials (polypropylene, stainless steel, aluminum…) and diaphragms (santoprene, PTFE…). 

These pumps are designed with two or three diaphragm chamber designs, also called electric double diaphragm pumps or electric triple diaphragm pumps. The industry leading product EVO Series™ of ARO is designed with three diaphragms and it gets the versatility of air operated diaphragm pumps with the efficiency and controllability of other positive displacement pumps. 

"100% electric drive for energy efficiency: with zero compressed air needed. This eliminates costly compressed air, increasing cost savings and tremendously decreasing energy consumption."

What are Electric Diaphragm Pumps Used for?

Electric diaphragm pumps have a wide range of applications due to their versatility. They are commonly used in various industries for tasks such as:

  1. Chemical Transfer: Electric diaphragm pumps are ideal for handling chemicals, ensuring safe and precise fluid transfer in chemical processing plants and industrial settings.

  2. Paint and Ink: These pumps excel at pumping viscous liquids like paints, varnishes, and coatings, providing consistent flow rates and ensuring a high-quality finish. Specific 3-chamber design of the EVO Series™ allows pumping product without shear nor pulsation, compared to traditional 2-chamber designs.

  3. Cardboard, Pulp and Paper: Electric diaphragm pumps are used in cardboard manufacturing processes to handle starch glue, offering the best solution for high efficiency and reliability. In addition, a 3-chamber electric diaphragm pump design provides longer intervals between maintenance and low pulsation.

  4. Lithium-ion Battery Manufacturing: With their ability to handle abrasive materials and powders, electric diaphragm pumps are suitable for carbon black and slurry applications, where durability and reliability are crucial.

  5. Industrial Wastewater: Electric diaphragm pumps find use in wastewater applications, pumping activated carbon fluids, thanks to their ability to maintain constant operation at multiple speeds. If electric diaphragm pumps include controllability, it can quickly increase flow to discharge a large volume of wastewater based on system requirements. The best pump solution for overall dosing tasks.

  6. Construction Waste Water: filter press filling is a common application with electric diaphragm pumps, used in various industries such as ceramic production or construction material manufacturing. Pumps can hold sufficient deadhead pressure to properly dry out filtered material – also control the density desired for the filtered material. Electric diaphragm pumps can increase flow rate compared to conventional pumps, from the same size due to torque limit control that promotes maximum filling of the filter press. If pumps include controllability features, users can control the pump from PLC interface to avoid manual operation.

EVO Series electric diaphragm pump of ARO pumping starch glue for cardboard manufacturing.

How Do Electric Diaphragm Pumps Work?

Electric diaphragm pumps operate using a reciprocating motion by means of a crankshaft system, which creates suction and discharge of the fluid. Let's explore their working mechanism:

  1. Suction Stroke: The diaphragm moves away from the pump chamber, creating a low-pressure area. This draws fluid into the pump through an inlet valve, filling the chamber.

  2. Discharge Stroke: As the diaphragm returns to its original position, it compresses the fluid within the chamber, increasing the pressure. The fluid is then pushed out through a discharge valve and into the outlet or discharge pipe.

  3. Valves: Electric diaphragm pumps use ball check valves to control flow direction. The inlet valve allows fluid to enter the pump during the suction stroke, while the discharge valve ensures one-way flow during the discharge stroke.

how does work an electric diaphragm pumpHow does an electric diaphragm pump work - 3 diaphragm chamber technology.

Electric Motor and VFD: An electric motor powers the crankshaft of the pump. Power supply depends on designs and technologies. EVO Series™ electric diaphragm pumps of ARO provide the following voltage and frequency options: 3 phase dual frequency 50/60Hz with 200-240V, 380-500V or 525-600V.

What are the Advantages of Electric Diaphragm Pumps?

Electric diaphragm pumps offer several advantages, making them a popular choice in many industries. Here are some key benefits:

  1. Self-Priming: Electric diaphragm pumps are capable of drawing fluid from a lower level, lifting it to a higher elevation without the need for additional priming equipment.

  2. Run Dry Capability: These pumps can operate without fluid, protecting them from damage in case of fluid shortage or interruption.

  3. Versatility: Electric diaphragm pumps can handle a wide range of fluids, including corrosive and abrasive substances. They can also handle different viscosities and temperatures, making them suitable for diverse applications.

  4. Simple and Compact Design: With fewer moving parts, electric diaphragm pumps have a straightforward design, enhancing reliability and simplifying installation, maintenance and repairs.

  5. Portability: Electric diaphragm pumps are often lightweight and compact, allowing for easy transport and maneuverability.

  6. Additional benefits only available on the EVO Series™ of ARO:

    1. High efficiency with exceptional energy savings compared to other positive displacements pumps

    2. Very Low pulsation due to the unique three chamber design, no need for pulsation dampener

    3. True Deadhead thanks to closed loop control that automatically stops pump’s spinning and hold pressure

    4. Leak Free due to secondary containment for fluid and oil, and automatic leak detection

    5. IIOT ready - Full integration through PLC or HMI devices

    6. Controllability - more controllable than any other positive displacement pump in its range

    7. All in one pump - no need to buy extra accessories

    8. High performance solution

    • Pump designed for long life even during high load conditions
    • High resistant diaphragms
    •  Low maintenance cost
    1. Hazardous duty certifications attending the most exigent worldwide safety standards covering environments with presence of hazardous liquids and gases


How to Install and to Program the EVO Series Electric Diaphragm Pump?

If you are looking for information on how to install and how to program the EVO Series Electric Diaphragm Pump, please watch installation videos on the ARO YouTube channel:

How to Repair an Electric Diaphragm Pump?

Repairing an electric diaphragm pump may be necessary for maintaining optimal performance. Here are general steps to follow:

  1. Safety First: Disconnect the pump from the power source and relieve pressure from the system.

  2. Diaphragm Inspection: Check the diaphragms for wear, damage, or leaks. Replace them if necessary, following the manufacturer's guidelines.

  3. Check Valves and O-Rings: Inspect the check valves and O-rings for wear or damage. Replace any faulty components to ensure proper flow and prevent leaks.

  4. Motor and Electrical Components: Examine the electric motor and other electrical components for faults or loose connections. Secure all electrical connections and verify the motor's functionality.

  5. Testing: Reconnect the pump to the power source and test its operation. Monitor for leaks or abnormal noises and ensure the pump functions as expected.

  6. To repair or maintain the EVO Series, please refer to the ARO YouTube video tutorial.


Remember to consult the manufacturer's guidelines and seek professional assistance if needed for a safe and proper repair process.

In conclusion, electric diaphragm pumps are reliable and versatile fluid transfer solutions. Understanding their working principle, applications, advantages, and repair procedures can help you make informed decisions and maintain your pumping systems effectively. Whether in chemical processing, cardboard, filter press, lion-battery manufacturing or other industries, electric diaphragm pumps continue to be one of the best valuable assets for fluid transfer needs among positive displacement pump technologies.