A common cause of failure on centrifugal pumps is operating too far away from best efficiency point (BEP) during normal operation. This can lead shortened life caused by cavitation or recirculation. These problems can cause erosion and damage to impeller and casing, premature failure of the bearings (especially the thrust bearings), seal or packing failures, damage to auxiliary equipment such as instrumentation and valves, and in extreme cases shaft deflection and breakage. Here is a demonstration of BEP. https://kvgo.com/Example/Find-BEP
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Reliability Guru 