Most companies today are working in a global environment where competition is hard. In order to be able to survive it is essential that the companies utilise their resources as much as possible in order to keep the production cost low. Maintenance plays a crucial role because of its impact on availability, reliability, quality and life cycle cost (LCC). However, being able to use maintenance proactively so as to increase the utilisation of the production process resources requires access to proper tools and methods for deciding on what maintenance to use and to follow up maintenance impact. Consequently, the overall research problem discussed in the thesis is: How to select a maintenance policy and follow up its performance with respect to cost-effectiveness in order to improve company profitability. In order to solve this overall research problem it has been broken down into four research questions R1: How can different approaches intended for maintaining or improving production process performance assist in the identification, analysis, elimination and prevention of recurrence of problems in a production process?, R2: How should maintenance be selected on the basis of cost-effectiveness?, R3: How should the technical and financial performance of maintenance be measured in order to enable cost-effective improvements? and R4: How to access relevant data required for cost-effective decisions in maintenance?. The philosophical basis applied in the work presented in this thesis is systems theory. When looking at maintenance, it is necessary to have a wide perspective and also see the interaction between maintenance and other relevant working areas. The major contributions that have been achieved and reported in the thesis are: 1. A literature review regarding current approach abilities to identify, analyse and prevent the recurrence of problems, 2. The development of a conceptual model for measuring the maintenance impact through a set of key performance indicators indicating where and how much to invest in maintenance., 3. The development of a maintenance support system for measuring the economic/financial impact of maintenance on both operative and strategic levels, 4. The development of a model for selecting and improving maintenance policies based on cost-effectiveness. The model presented is characterised by being flexible, in the meaning that it is possible to make a selection among any types of maintenance policies., 5. The definition and description of a common database containing relevant data for maintenance management and 6. Results from an exploratory study regarding IT maturity within maintenance management in Swedish industry are presented. The main conclusion of the thesis is that the tools and methods described in this thesis can represent important elements in a system to continuously and cost-effectively improve maintenance performance and thereby better utilise the resources in the production process.

This thesis describes the role of cost effective maintenance in achieving competitive advantages. It explores by means of a survey which maintenance practices are used, and how maintenance policies are selected in Swedish industries. Also, it suggests a model for selecting the most cost effective maintenance policy, and how to improve the effectiveness of condition based maintenance decision-making. Finally it discusses how to assess the impact of maintenance practices on business strategic objectives. The main results achieved in the thesis are 1) A better understanding of maintenance organisation, management, systems and maintenance status in Swedish industry. For example, it was found that about 70% of Swedish companies still consider maintenance as a cost centre. Preventive and predictive maintenance approaches are also emphasised. 2) Most Swedish firms, i.e. about 81%, use the accumulated knowledge and experience within the company as a method for maintenance selection. Besides, about 31% use a method based on modelling the time to failure and optimisation. About 10% use failure mode effect and criticality analysis (FMECA) and decision trees and only 2% use multiple criterion decision-making (MCDM). However, the most used maintenance selection method is not the one most satisfactory to its users. Furthermore, about 30% use a combination of at least two methods. 3) A practical model for selecting and improving the most cost effective maintenance policy was developed. It is characterised by incorporating all the strengths of the four methods used in industry. 4) A mechanistic model for predicting the value of vibration level was verified both at the lab and in a case study. 5) A model for identifying, assessing, monitoring and improving the economic impact of maintenance was developed and tested in a case study. Thus it was proved that maintenance is no longer a cost centre, but could be a profit-generating function. To achieve competitive advantages, companies should do the right thing, e.g. use the most cost effective maintenance policy, and they should do it right, e.g. ensure that they have the right competence. Furthermore, they should apply the never-ending improvement cycle, i.e. Plan-Do-Check-Act, which requires identifying problem areas by assessing the savings and profits generated by maintenance and monitoring the economic impact of the applied maintenance policy. Thus, they would know where investments should be allocated to eliminate the basic reasons for losses and increase savings. The major conclusion is that proper maintenance would improve the quality, efficiency and effectiveness of production systems, and hence enhances company competitiveness, i.e. productivity and value advantages, and long-term profitability.