INTEGRATION OF DEGRADATION MODELS FOR THE PURPOSE OF MAINTENANCE OPTIMIZATION
Viraj Kharagjitsing - Strukton Rail (July 2021)
SUMMARY
Between various types of transportation, railways have played a significant role in modern transportation and social development. Currently, the railway industry is facing higher demands (30% growth, expectations regarding 24/7 availability, and timetable punctuality), which in its turn demands higher railway track performance, resulting in less time for maintenance execution. In 1995, the NS departments, which were responsible for track maintenance, were privatized under the name ProRail. ProRail publicly tenders projects, and these are then auctioned among the Maintenance Service Providers. Strukton Rail Netherlands (SR-NL) is one of the largest maintenance service providers in the Netherlands today. To stay competitive SR-NL must keep up with innovations and new technologies which are being developed. As SR-NL is responsible for providing maintenance solutions and advice in the form of maintenance concepts, it is necessary to constantly iterate on the maintenance process. Degradation modeling is one of the terms which is of use for providing maintenance solutions and giving out maintenance advice. Within this thesis, research is done on the effects of adding a newly developed rail wear model.
Within SR-NL rail wear and Rolling Contact Fatigue defects are also among the degradation mechanisms which are assessed. Wear and RCF are failure mechanisms that are the result of high stresses caused by heavy loads and vehicle dynamics within the wheel-rail contact. The current method of maintenance concept development is done using the Plan, Do Check, Act method in a generic framework in which the asset has four basic steps for the development of the maintenance concept. This is supported by the expert knowledge in Reliability Centered Maintenance, Fault Tree Analysis, and Failure Modes Effects and Criticality analyses. This information is used to set up preliminary maintenance concepts whereafter the data is analyzed and planned out using tools such as SAP (for planning and scheduling maintenance activities) GIS (for visualization) and the IRISSYS® platform for degradation modeling.
The Innovation Management Plan was also used to identify what requirements are needed for the implementation of the newly developed model. Furthermore, the generic framework which is used within the company was improved upon. Using a Strengths, Weaknesses, Opportunities, and Threats analysis, it became clear what the shortcomings are. Improvements were then made to the generic framework. Guidelines were also utilized (the (PAS)55/ISO55K series) to aid in building the improved framework. Within the framework, the newly developed model and its conditions were incorporated.