ABSTRACT
Nuclear Feed Pump Cyclic Thermal Rotor Bow troubleshooting case was presented for the author's investigation after the plant owner company conducted an extensive but unsuccessful in-company project to alleviate a vibration problem in all the feed water pumps in a plant housing two 1150 MW pressurized water reactor (PWR) generating units. Only after several months of unsuccessful in-company vibration measurements and troubleshooting diagnoses of this excessive vibration problem, the author was retained by the power company owner to see if a rotor vibration computer model analysis could identify the root cause of the excessive vibration. The rotor vibration computer analyses included investigations for root causes from critical speed resonances and instability self-excited rotor vibration phenomena. It was no surprise to the author that these analyses eliminated critical speeds and self-excited vibration phenomena as likely root causes, but the plant insisted upon these analyses as the first step.
