Maximise your Pump Efficiency

With 87% of the cost of pumps represented by operational expenses, achieving energy savings can provide a sizeable cost reduction. In fact, taking the right steps to increasing pump efficiency can conclude in savings of 10-15% on a pump, or 30-40% across an entire pump assembly.

Theory versus practice

Every pump has a theoretical output, which almost always invariably differs from its actual output. The factors for this include:

• Manufacturers usually add a safety margin to a pumps performance, meaning the operator has to throttle it back to achieve the correct duty point – resulting in the pump not operating at its optimum
• Changes and modifications to pipework within a pump system can affect pressure, flow and pump efficiency
• Service wear, often through corrosion or erosion, reduces efficiency, but as a low-efficiency pump can still perform, losses may go unnoticed

Causing pumps to move away from their Best Efficiency Point (BEP), these issues lead to higher operating temperatures and cavitation, which in turn can affect bearings and seals, shortening the pumps life significantly.

Contrary to popular belief, maximum efficiency isn’t achieved by adding more pumps to your system, with that said, in some cases, multiple pumps systems offer great energy savings if the system requirements fluctuate (i.e washdown sets).

Remedies for energy savings

Variable speed drives should be considered for energy savings, as they have a particularly positive effect in a closed loop system. Trimming the pump impeller is also another viable option.

Know-how and maintenance also plays a vital role in returning pumps back to their BEP. Maintaining clearances on wear rings between suction ports, for example, will help keep the most in its most efficient state.

Finally, regular health checks will allow a pumping cost by product flow calculation in order to determine the point at which the cost of pump refurbishment will be fully financed by the energy saved. Not all pumps are suitable for this type of monitoring regime, buy if a pump is over 37Kw and operates for over eight hours a day, it’s highly likely that the regime can be financed by the energy saved.

Interested in making these savings? Call one of the highly skilled ERIKS technicians on 0121 508 6000 for further information.