In today’s uncertain economy, keeping pumping systems and stations operating at their optimum capability is vital. However, many organizations responsible for this crucial task do not perform regular health checks on their pump systems.
Most people would not run their car or home heating units until they break down or stop working. Similarly, most people maintain their health with visits to the doctor or dentist.
The same principles apply to pump systems. They require the same level of preventive care and maintenance so that operators and end users benefit the most from their investments. Preventive maintenance and monitoring provide a clear picture of the pump system’s performance, save end users money and reduce environmental impact by improving energy usage.
The maintenance of a pumping station should not be a one-time event. A robust monitoring system along with regular health checks will deliver an accurate understanding of how a pump system is performing.
When end users consider the different options for monitoring performance, they should look for a system that monitors energy use, the whole life-cycle cost of the equipment and how the pump performs against its most efficient duty point. Also, maintenance records can reveal any fault trends that will help predict or diagnose pump failure, regular breakdowns or loss of performance. This information can assist the operator in planning maintenance and controlling the budget.
Continuously-improving technology has resulted in the increased accuracy of system variable measurements. Monitoring equipment can measure pressure, flow, depth, energy consumption, vibration and temperature, without the need to drastically modify the pump station layout.
A modern monitoring system can accurately obtain and record precise data, including trends of all the hydraulic and power inputs, which display in real time as the pump operates. A visual display such as this is more informative than basic numerical data logging and can be invaluable in providing information for system troubleshooting.
Having access to the data obtained from a monitoring system is particularly important because each system or station has a different set of requirements. In general, pumps are selected based on the most efficient duty point designated by the manufacturer. Selections are most often made from desktop designs and drawings.
However, even in the best circumstances, installation of a pump system/station rarely occurs exactly according to plan. This means that the pump will probably operate outside its best efficiency point. Once installed, its performance can be monitored and adjustments can be made, such as an impeller trim or speed change on the variable frequency drive. For pump upgrades and replacements, knowing the precise pumping station system data makes accurate and efficient pump selection easier.
One example of the importance of understanding a station’s requirements occurred at a station in Pembrokeshire, West Wales. An original pump had not met the required capacity. The operator, not understanding his pump system, installed an identical pump system adjacent to the original one, and this station included very large pumps. Nothing was physically wrong with the pumps, apart from being incorrectly selected. By chance, someone involved with the station called a pump system engineering firm, and the installation of a third identical system was avoided.
This firm carried out a full health check and system analysis and suggested that a different pump should be selected. As a result, the operator saved thousands in construction, plant and wasted energy costs.
Adjusting the System Over Time
As time passes, conditions change. Components wear. Parts may be added or removed, and these changes can completely alter the system’s operation. More often than not, particularly if there is no health check in place, these changes are not taken into account. However, they have altered the footprint of the originally installed system.
Over time, pipes can become partially obstructed because of silt and debris build up, or local damage may occur in which pressure from the surface has damaged or misshaped a buried pipe. Unlike our bodies, which provide signals such as pain when they are damaged, the only signals a faulty pipe will give are problems, such as flooding or a reduction in output. In most instances, pump station operators can only see the external picture. They know that the system is not working as it should, but they have no data to support their concerns.
Many common pump station issues do not show up immediately. For example, the poor design of wet well benching or in-flow paths can lead to cavitation, pump wear and reduced performance. Analysis of the pump system throughout operation will indicate the telltale signs of performance deterioration.
In an ideal world, and particularly when it comes to large pump systems or stations that use a lot of energy, the operator should perform regular health checks through a robust and reliable monitoring system that considers all aspects of the process. This includes a software system that runs seamlessly with the pumping equipment and records data, which can be viewed remotely at any given time for a performance analysis.
Key Elements of Analysis
Products are available that can show end users how the key elements of their pumping system are operating. These elements include pressure, flow, vibration and temperature. These parameters, combined with audio monitoring, provide operators with the big picture and many small problems before they become big issues.
The purpose of a health check and monitoring system is to ensure that pump systems operate at optimum performance as designed. If end users decide to employ a specialist engineering organization to perform this service, it can use the data that it gathers to advise them on their system performance, energy use and efficiencies. If performance is poor, the service provider should recommend possible causes and remedial actions.
Many of us live by the mantra, “If it isn’t broken, don’t fix it.” However, because of this mentality, some pump system operators are pouring money down the sewer. Even if the pump well empties or the station does not flood, does not mean that problems do not exist and improvements cannot be made. If problems are left unresolved, one day the system will fail, which can result in expensive outages and repair or replacement costs. Failure can also cause environmental issues. All of this can be prevented through a regular health and maintenance program.
Small Repairs Result in Large Savings
When it comes to poor performance, the issue may not be with the pump but with an associated part—an impeller, for example. A big bill can easily be avoided by having the right system, working in the right way and delivering the desired result. Small repairs and changes can make a big difference to performance. However, without identifying possible issues, how can an operator know what needs to be done?
Analysis Before Replacement
Replacing a pump with the exact same pump is no longer a practical or viable option. If a pump replacement is essential, then the whole pumping system should be analyzed before investing in a new pump. This is because, over time, the surroundings in which the pump operates is likely to have changed, possibly because of the environment, local construction, changes in weather conditions or a host of other potential causes. Again, a regular health check of the system will have identified these changes on an ongoing basis, supplying the operator with the knowledge required to make an educated pump purchase.
Addressing problems in pumping systems is a constant challenge for operators. They should think of their pump system as a finely tuned engine that needs the same level of care and attention as a car’s engine. With state-of-the-art monitoring technology at their fingertips, improving the performance of pump systems is easier than ever, without the expense of costly replacements or excessive energy use. If operators are not monitoring their systems or conducting regular health checks, the question to ask is “Why?” P&S