Failure analysis on a cooling water pump of the power plants

A failure analysis on a cooling water pump (CWP) of the coal power plant has been properly carried out. This seawater suction pump is one of four similar pumps operated at the same load. The pump started operating in 2016 and was damaged in 2019. Early detection of the pump starting to operate abnormally was from the vibrations, exceeding of permissible tolerance limits. Failure analysis was scanned initially from visual observations of the pump, vibration and cathodic protection data, XRF-chemical composition, hardness and microstructures. Pump malfunction was detected fromthe impeller not working normally. The pump impeller material is known to be severely damaged. Laboratory testing usinga scanning electron microscope (SEM-EDS) and penetrant tests was carried out to better understand the material microscopic occurrences. Analysis was deeply investigated by assessing the cathodic protection system (condenser) of thepipe and continued by testing its thickness at several locations experiencing leaks. It can be concluded that the CWP workfailure is caused by the impeller being damaged due to stress corrosion cracking (SCC). The similar components used in other CWP pumps would probably not be able to survive until the design life.