Experience of Condition Based On-Line Vibration Monitoring System for Rotodynamic Equipment of Nuclear Research Reactor

Nuclear Research Reactor is utilized for the production of radioisotopes and offer irradiation facilities for testing various materials such as nuclear fuel & structural materials. During normal operation, the primary cooling is achieved by circulation of Heavy Water by Primary Coolant Pumps (PCPs) and the secondary and tertiary cooling is achieved by Process Water Pumps (PWPs) and Sea Water Pumps (SWPs). However, on power failure or outage of PCPs, Heavy Water is circulated through core by means of Auxiliary Coolant Pumps (ACPs). Condition Based Monitoring of Rotodynamic equipment has been a regular feature in nuclear plants. It not only assures higher safety and reliability for plant systems but also helps in timely and economic maintenance activities. Vibration based condition monitoring programme was put in practice at research reactor, in mid-eighties which grew up with time and about 30 equipment for which predictive based maintenance activities were taken up based on condition monitoring inputs. Offline vibration measurements were able to identify the bearing defect and root cause but could not identify the motor degradation in real time. An Online Vibration Monitoring System (OVMS) was implemented for continuously monitoring the dynamic behaviour and to identify deviation or degradation in real time for important rotodynamic equipment to achieve higher availability. This paper provides the detailed account of the experience of Condition Based On-line Vibration Monitoring System for rotodynamic equipment’s of Research Reactors, its salient features, advantages, challenges faced in implementation and performance of the system.