Understanding Electrically Operated Diaphragm Pumps: Functionality and Applications

Understanding Electrically Operated Diaphragm Pumps: Functionality and Applications

Electrically Operated Double Diaphragm (EODD) pumps operate via a back-and-forth movement of two diaphragms (a flexible membrane typically made from materials like rubber, Teflon, or thermoplastic), which results in the movement of the fluid. These pumps serve several industries, including ceramics, sanitaryware, paints & dyes, metals & mining and oil & gas. They are known for their performance, reliability, ability to handle many fluid types, and superb resistance to harsh conditions.

First, here is a little bit about how EODD pumps work. To explain it to a layman, an EODD pump focuses on the following mechanism:

Suction stroke – Imagine a closed pump body. Now, imagine the first diaphragm moving backwards. This movement creates a vacuum, which helps draw fluid into the pump chamber through an inlet valve.

Discharge stroke – Now imagine the diaphragm moving forward while putting pressure and forcing the fluid out of the pump body through an outlet valve. That is the discharge stroke for you.

What moves the two diaphragms is an electric motor, an AC or DC motor, to be precise, which eliminates the need for a conventional air compressor. This motor is connected to a gear system to convert rotational motion to a reciprocating motion. It is this reciprocating motion that allows for a controlled and precise diaphragm movement.

EODD pumps are preferred over other pumps for several reasons, including the following:

They are self-primed - EODD pumps are motor-driven and can operate even when no fluid is sucked in. The capability to operate in dry run conditions makes EODD pumps an excellent choice for applications which handle inconsistently supplied fluids.

They are energy-efficient - EODD pumps do use electricity. However, they judiciously consume electricity, making them an energy-efficient choice.

They offer precise flow - The motor that powers both the diaphragms of an EODD pump can be adjusted for speed, allowing for a controlled, accurate flow control.

They create less noise - Unlike AODD pumps, which generate a lot of noise during operation, EODD pumps are quieter.

Because of all the benefits we just discussed, EODD pumps find their place in several industries, such as:

Chemical processing - EODD pumps are made of robust, corrosion-resistant materials and have a leak-proof design. This makes them ideal for chemical industries where aggressive chemicals and acids must be transferred.

Food & beverage industry - EODD pumps do not just ensure hygienic fluid transfer for products like syrups, dairy, and beverages, they also, via precise flow, provide the final consistency of the product.

Oil & Gas - Since EODD pumps can handle high-viscosity fluids, slurries, and hazardous substances, they are ideal for refining and drilling operations.

Water and wastewater treatment - EODD pumps, with their precise flow and leak-free performance, are also suited to pump sludges, chemicals and wastewater efficiently.

Cognito Pumps – Built to transfer the world's most challenging fluid transfer applications

In collaboration with Warren Rupp, Inc., a global leader in diaphragm pump design, Cognito has been supplying world-class advanced EODD pumps for more than 30 years. The brand has won several awards, including the latest for Most Innovative Energy Saving Product by CII 2023-24.

The USP of Cognito's pumps is their patented diaphragm with a larger diameter and shorter stroke. The combination of the two gives Cognito EODD pumps an extended lifespan. Cognito EODD pumps also feature a hardened seat which lasts for years. Cognito EODD pumps rely on secondary static seals that prevent any fluid contact to offer a leak-free operation. Additionally, the leak detector can communicate to the PLC to stop the pump in case of a leak. The pumps are provided in two configurations – horizontal and vertical. This reduces the pump's overall envelope size and allows customers to pick a configuration adaptable to their applications.

Now, let's dive into the industries and the various applications that have used Cognito's EODD pumps and are really happy with them.

The ceramic industry - One of the main challenges faced by ceramic industry applications is their long running hours which put a lot of pressure on traditional pumps. EODD pumps, however, are up for the task as they are built for energy efficiency and extended operations.

Paints & Dyes industry - Applications in the paints & dyes industry have to deliver high-quality output without changing the product's look and feel. Cognito's EODD pumps feature a gentle pumping action that prevents product degradation at all stages of operation.

Metal and mining industry - Metal and mining industry applications can face downtime if the pump doesn't have dry-run capabilities. Cognito's pumps can run dry without any damage and handle solids and abrasive fluids without wear and tear, offering more extended operation.

To sum it up, Cognito's EODD pumps can handle hundreds of fluids and are built for applications of all kinds. They are energy-efficient, and can handle high pressures and a range of temperatures. To know more about Cognito  and its EODD pumps' portfolio, please visit their website: https://www.cognitopump.com/