One of the big challenges in MYRRHA is the loading and unloading of the fuel into the reactor core, submerged in liquid metal. The hostile environment necessitates the use of robotic arms for fuel handling and maintenance activities. However, corrosion and embrittlement from the liquid metal, high temperatures and lack of lubrication combine to make very unfavourable conditions for the mechanical components in these robotic arms. SCK-CEN has designed and built a unique test facility, RHAPTER, to study the behaviour of electrical cables, gears, leadscrews, ball bearings and journal bearings – basically all mechanical components required to build a functional robot – operating in liquid metal.
Five years of experiments in RHAPTER have given us extensive experience with mechanical systems in LBE, in particular with the operation and analysis of rolling element bearings in LBE. Today, the focus of our research is shifting towards journal bearings. However, the analysis methods developed for rolling element bearings experiments are not readily transferable towards journal bearings, as the sliding friction encountered there results in different wear mechanisms and different dynamic behaviour. This Post-Doc aims to contribute to the experimental programme for journal bearings, translating our experience in bearing analysis to journal bearings and developing analysis methods specific for journal bearings in LBE.