Air-operated double diaphragm (AODD) pumps can be a more reliable choice than centrifugal pumps in many situations. A centrifugal pump design is simple, with easy to understand pumping principles. But they are one of the most difficult industrial pumps to choose for an application.
There are many interrelated design and set up variables that must be correctly determined for a specific application for a centrifugal pump to work as designed.
If the pump and process are set up properly, the pump works very well. However, even small changes to process conditions — flow, pressure, fluid viscosity, NPSHa, or particle level — can dramatically reduce the efficiency and reliability of the centrifugal pump. Rarely, if ever, are these pumps rechecked for viability after any process changes.
Centrifugal pumps are often a source of chronic maintenance and reliability problems. They are designed to operate near a single operating point or Best Efficiency Point (BEP). Moving process conditions even 10% from this point can cut the reliability in half and dramatically lower the efficiency.
How often do process engineers revisit the pump configuration when they make a change to process? Answer: Very rarely, if ever.
An AODD pump is easier to specify for an application and can run reliably across the entire rated operating range, not just a single point.
These are five common issues or applications where an AODD pump could be a better solution.