46 Condition Monitoring
The positive impact of condition monitoring
When rotating equipment like pumps and motors are running smoothly, it is easy to overlook common maintenance tasks and justify that it is not worth the time to regularly inspect and replace parts. Houghton International explains why it is vital to ensure that such equipment has a programme of maintenance.
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y adopting a maintenance programme for a critical pump, a business can prevent costly downtime and improve performance. A good maintenance programme will help identify a problem in its infancy, allowing users to put a plan in place to carry out repairs during a shutdown period. It also lets users maintain pumping capacity to ensure a pump is running as efficiently as possible and reduce future costs by prolonging its life. Routine preventative maintenance practices should include the monitoring of bearing temperature, vibration, bearing lubrication, amps (power) readings, suction and delivery pressures. By comparing them to the test and commissioning data, users can set a predetermined level of internal wear, which is acceptable to the process and the pump, to use as the basis of a maintenance plan. It is also worth noting that during an annual assessment of a pump’s performance, any changes in the benchmarks can be recorded and used to determine the level of maintenance that may be required to get a pump back to operating at its Best Efficiency Point (BEP). When planning the maintenance of a pump as part of a predictive maintenance programme, it is worth considering condition monitoring. Condition monitoring is performed to highlight a pump's decreasing performance, as opposed to undertaking maintenance at predefined scheduled intervals. It is a maintenance approach that monitors the actual condition of a pump to decide what maintenance needs to be carried out on specific pump components when a set level is reached. Another benefit of adopting this maintenance approach is that it is performed while a pump is running, which reduces the disruption to normal operations and reduces the cost of pump failures, increasing reliability and minimising the overall time spent on maintenance compared to a reactive approach. Also, this method will identify when the pump is running left of the BEP and therefore running less efficiently. Another advantage of ongoing condition monitoring is that data readings can be digitally stored, reducing the need for manual input. Techniques such as vibration analysis can help detect many serious problems at an early stage, allowing maintenance engineers to undertake remedial work at a time that suits. All rotating electromechanical equipment exhibits a varying degree of vibration, but by utilising a vibration sensor, you can detect how excessive the Quarter 2 2021
vibration is. Vibration can be measured in three basic quantities: displacement, velocity, and acceleration and should be measured when the pump is at its normal steady-state operating condition. It is a non-intrusive, fast response, preventative maintenance solution, designed to locate a potential problem and rectify it before it causes further damage to the machinery. Laser alignment is another key part of the overall condition monitoring process and gives users a firm printed report, which is unchangeable. As with vibration analysis, laser alignment detects the smallest deviations in the shaft to provide an accurate warning of possible breakdowns. Oil and lubrication analysis, on the other hand, is one of the easiest and most effective condition monitoring methods. Trending particle counts can be an early sign of bearing and seal wear long before vibration analysis can be effective. There are, however, a few points to consider when planning to implement condition-based monitoring as part of your maintenance programme. The initial investment cost of the measuring equipment and sensors, as well as the subsequent installation, needs to be taken into consideration and even then, particularly on older equipment, users might have to make modifications to allow monitoring equipment to be retrofitted correctly. There is also the time and money investment in up-skilling maintenance staff to ensure that they can use the condition-based monitoring equipment correctly and safely. All things considered, the benefits of adopting a predictive maintenance system such as conditionbased monitoring have become well accepted and can help prevent costly downtimes, ensure pump efficiency and reduce costs. TIMES-CIRCLE www.houghton-international.com www.theaemt.com
