Centrifugal pumps are used in many different industries, such as water and wastewater, chemical processing, power generation, and food and beverage. In today’s market, companies are looking for new and better ways to lower energy usage and operating costs — and centrifugal pump optimization can achieve this.
Best Efficiency Point
An important element of the centrifugal pump curve is the best efficiency point (BEP). Every centrifugal pump has a BEP. At this point, the pump operates most cost-effectively in terms of maintenance and energy efficiency. As a result, the operating efficiency is highest, and the radial bearing loads are lowest.
Factors that Deteriorate Pump Efficiency
Centrifugal pump efficiency boils down to three different efficiencies: volumetric, mechanical, and hydraulic.
- Volumetric efficiency – Volumetric efficiency involves the losses caused by internal leakage through the wear rings and balancing holes.
- Mechanical efficiency – This efficiency determines the amount of power a pump must have to perform optimally. Things like losses in bearings and mechanical seals will affect mechanical efficiency.
- Hydraulic efficiency – Among the three efficiencies listed here, hydraulic is the most significant. Components that affect the hydraulic efficiency of a centrifugal pump are the impeller and volute casing. Liquid friction also plays a role.
How to Increase Centrifugal Pump Efficiency
Energy efficiency is an essential topic in the pump industry. Below, the PumpWorks experts cover several ways you can achieve energy savings on your pumping systems.
Properly Match Component Sizes and Load Requirements
The first step in any pumping operation is to ensure your pumps and components are appropriately sized for your infrastructure. Pipes are limited to how much fluid they can move at a certain pressure. If they aren’t sized properly, your motor will have to work harder, and you’ll lose efficiency. No amount of lubricant or maintenance work will help.
Perform Regular Maintenance
Staying up-to-date on your pump maintenance is proven to reduce energy consumption. As like with any machinery, wear and tear can reduce efficiency. Proper pump upkeep includes replacing eroded wear rings, inspecting for damage, analyzing the temperature and vibration, adjusting oil levels, and much more.
Use Variable Frequency Drives
Variable frequency drives (VFDs) allow the pump to operate near its best efficiency point at any head or flow demand of the application. VFDs can also be programmed to protect the pump from mechanical damage during specific stages, thereby improving mechanical reliability. Although VFDs are costly, the energy savings they can make will justify the investment in the long run.
However, it’s important to note that VFDs are not suitable for all applications. For example, a VFD wouldn’t be practical for a system that operates for extended periods under low-flow conditions.
Downsize Pump Impellers
An easy and cost-effective way to reduce the pressure and flow of oversized pumps is to size down the impellers. Like VFDs, impeller trimming is a great way to make your pumps more energy efficient. Of course, VFDs are still more efficient, but this solution works better than using a throttling valve.
Eliminate Unnecessary Pump Use
It’s shocking how often pumps are in operation unnecessarily. Implementing control systems to shut down pumps not in use can improve efficiency. Additionally, pressure switches can control the number of pumps in action to ensure multiple pumps are in use necessarily.
Keep Pumps Lubricated
Lubrication is the number one enemy of friction, which plays a considerable role in centrifugal pump efficiency. Therefore, operators should monitor lube tanks or sumps and check lubricant usage levels for inconsistencies. If lubricant consumption goes up, this can indicate that friction has increased in the system and should be addressed immediately.
Train the Pump Operators
A well-trained operator is critical for efficient pump operation. Pump operators and other authorized personnel should know how to monitor system performance and perform routine maintenance. Train key staff members to report any issues with system pressure or flow rate and have a course of action in place. Taking these measures will ensure your systems operate at the most efficient levels.
Contact PumpWorks for All Your Centrifugal Pump Needs
Finding the perfect centrifugal pump can be challenging, so let us help! PumpWorks is a trusted manufacturer of ANSI centrifugal process pumps and API process pumps in Houston, Texas. We specialize in pump services and repair work and are ready to help you anytime you need it.
Contact us online today to learn more about improving your centrifugal pump efficiency.
