FöRFATTARE
Granström, Rikard

INSTITUTION
Samhällsbyggnad / Drift och underhållsteknik

SAMMANFATTNING
Due to the increasing need for transportation and environmental concerns, there is a social and political will to transfer transportation services from roads to rail. The increasing demand for railway transportation services has a significant effect on important stakeholder requirements, such as safety, punctuality, dependability, sustainability and costs. This in turn affects railway practices concerning operation, maintenance and modification. Simultaneously, the ongoing deregulation of state-owned railways has caused new organizations to enter the railway sector. Hence, the punctuality of the railway is dependent on a combination of multiple required functions that are concurrently provided by different stakeholders, e.g. the infrastructure manager, infrastructure maintenance contractors and traffic operators. In Sweden, Banverket (the Swedish National Rail Administration) is the infrastructure manager and has the overall responsibility for railway punctuality. This means that Banverket has to coordinate and stimulate the stakeholders to provide the required functions in order to achieve the delivery of punctual transportation services.

The purpose of this research is to explore and describe how information about the condition of technical systems can support stakeholders within the Swedish railway in improving punctuality by means of more effective and efficient maintenance. The focus is on delays that are caused by the absence of required infrastructure functions, even though the interaction with the rolling stock is considered through the study of critical interfaces. Condition monitoring technologies are focused on as the primary application for obtaining condition information on technical systems. Hence, the research is intended to provide knowledge about how condition information can be used in the quest to provide the quality required from the Swedish railway transportation service at an adequate cost for society. To fulfil the stated purpose, empirical data have been collected by document studies, interviews, work-shops, observations and field measurements. Examples of covered data are train delay statistics, failure statistics, No-Fault-Found events and wheel impact forces. The data have been analysed through statistical and analytical approaches (e.g. Failure Mode and Effects Analysis, FMEA), as well as by applying theories related to principal agent problems, Scientific Management and international dependability standards.

The thesis describes how the maintenance effort required by infrastructure maintenance contractors is affected by the maintenance effort conducted by traffic operators (and vice versa). The interaction between infrastructure and rolling stock has a significant effect on the systems' punctuality and the degradation of bound capital. Hence, effective punctuality improvements through maintenance efforts must be based on a holistic railway system perspective, i.e. a joint consideration of infrastructure and rolling stock. The thesis also presents how condition information can be used as a management tool to stimulate the fulfilment of performance requirements made on railway stakeholders. It is also shown that the same information can be used to predict and plan necessary preventive maintenance tasks, as well as to support continuous improvement of the technical systems. However, unless stakeholder needs are acknowledged and unless proper scientific investigations precede the formation of requirements and the applications of condition monitoring technologies, it is likely that the desired system performance improvements will not be realised. In summary, the thesis outlines a possible scenario in which condition information could support railway stakeholders in improving the punctuality of the railway system by means of more effective and efficient maintenance.

ISSN 1402-1544 / ISRN LTU-DT--08/36--SE / NR 2008:36