The existing maintenance programme is more or less based on the suppliers’ recommended programme. However, current and planned utilisation of the fleet varies significantly from the utilisation assumed in the suppliers’ baseline programme. There was consensus that at this point sufficient technical and operational experience had been accumulated about the train sets (which entered into service in 1996) to re-evaluate the maintenance programme.
As a member of the project group, DSB S-Tog engaged Scandpower to work on the project to establish the method approach and lead the analysis activities. A working group of 14 members was formed including personnel within all relevant disciplines, such as engineering, workshops, planning, logistics, etc. The working group reports to the project steering committee. Specific maintenance cost targets and programme change criteria were defined for the working group. The changes to the maintenance programme are to:
- Maintain the level of operational safety demonstrated by risk assessment complying with the EU Common Safety Methods (CSM);
- Maintain or improve operational regularity;
- Improve operational availability;
- Maintain quality and passenger comfort;
- Meet the project’s maintenance cost reduction targets.
Scandpower has experience from a number of similar projects performed on electric and diesel-driven motor units, EMU/DMU, locomotives and passenger cars. The analysis approach comprised a method based on the standard IEC 60300-3-11, “Application guide – Reliability centred maintenance”, and includes safety critical functions and barrier modelling for maintenance tasks on all safety critical systems and equipment. Hence, the method complies with the project’s defined criteria and the CSM regulation as stipulated in EU Directive 2004/49/EC. In addition the method expands the opportunity set for continuous improvement of the maintenance programme by analysing the impact of the maintenance task on operational effect (RAMS).
Two working group sessions were conducted for a total of five days. The working group is currently finalising the analysis report. The application for the maintenance programme change will be submitted to the Danish Transport Authority, Trafikstyrelsen, by mid-February 2012. A preliminary evaluation of the analysis results shows compliance with the safety and regularity criteria, and a preliminary estimation of the potential maintenance cost reduction of 20-25% indicates that project targets will be met.