As a result of global competition, companies within the automotive industry are required to improve their production systems to achieve sustainable and competitive production. To attain operational excellence, companies have adopted concepts like lean and World Class Manufacturing (WCM). In order to deliver, companies need to increase the availability and reliability of production equipment. This demands focus on both operational and strategic maintenance, and efficient equipment acquisition and management. The main objective of this thesis is to identify processes and success factors that are necessary for improved maintenance performance. By conducting a case study and by performing a literature review, the following has been studied: 1) how companies within the automotive industry work with maintenance and maintenance strategies, 2) implementation of maintenance strategies, and 3) new acquisition and spare parts management for maintenance.  The results show that basic maintenance concepts and related terms are well defined in the literature. However, maintenance strategy is not unanimously defined. Results from the case study reveal that Professional Maintenance (PM) within WCM has been considered as a maintenance strategy. Furthermore, driving forces and obstacles for implementing maintenance strategies have been identified. The study also reveals that there is a strong link between maintenance performance, new acquisition and spare parts management. / Den globala konkurrensen inom fordonsindustrin, har medfört krav på företag att effektivisera sina produktionssystem för att åstadkomma en hållbar och konkurrenskraftig produktion. Detta har resulterat i arbete enligt koncept som lean och World Class Manufacturing (WCM).  För att kunna leverera behöver företag öka den tekniska tillgängligheten på utrustning. Detta i sin tur ställer ett ökat krav på både operativt och strategiskt arbete med underhåll, anskaffning och reservdelsstyrning. Målet med examensarbetet är att identifiera processer och faktorer som bidrar till ett förbättrat underhåll. Med hjälp av litteraturstudie och en fallstudie har följande studerats: 1) hur företag inom fordonsindustrin arbetar med underhåll och underhållsstrategier, 2) implementering av underhållsstrategier, och 3) nyanskaffning och reservdelsstyrning för underhåll. Resultat från litteraturstudier visar att det finns en enighet om att underhåll delas in i förebyggande och avhjälpande underhåll. Däremot, visar resultatet att det inte finns en enig definition av underhållsstrategi. Fallstudien visar att Professional Maintenance (PM) inom WCM betraktas som en underhållsstrategi. Som ett resultat har även ett antal drivkrafter och svårigheter som påverkar implementering av underhållsstrategier identifierats. Vidare visar resultatet att det finns ett starkt samband mellan underhåll, nyanskaffning och reservdelsstyrning.

Företag kan använda sig av olika strategier för underhåll. Det kan vara avhjälpande underhåll som utförs först när ett fel uppkommer eller förebyggande underhåll. Ofta används en kombination av båda. Det förebyggande underhållet kan vara förutbestämt eller tillståndsbaserat. Fördelar med att använda sig av tillståndsbaserat underhåll är exempelvis att utbyte av enheter inte behöver ske i onödan utan först när en observation visar att ett fel är på väg att ske. Vid val av förebyggande underhåll kan RCM-metoden användas för att utröna vilka feltillstånd som kan uppstå och som orsakar funktionsfel. Val av förebyggande underhåll kan baseras på fakta om nya tekniker, felhistorik samt vilken utrustning och kompetens som finns tillgänglig. Volvo Cars i Skövde använder sig just nu av i stort sett likadant förebyggande underhåll på nya verktygsmaskiner som på gamla. Företaget använder sig av tillståndsbaserat underhåll på vissa komponenter och enheter. Det består då främst av inspektioner, subjektiva tillståndskontroller, och vibrationsövervakning på motorspindlar. Genom intervjuer framkommer att nya tekniker sällan införs och att lagda planer sällan ändras. Företaget är dock medvetet om att nya tekniker för tillståndsbaserat underhåll finns och är intresserat av att undersöka om ett utökat tillståndsbaserat underhåll är lämpligt på verktygsmaskiner. De tillståndsbaserade teknikerna som det talats om är främst ballbarmätning, övervakning av processparametrar och geometrisk verifiering. Ett underlag för att se om nya tekniker bör införas togs fram genom datainsamling av felhistorik på maskiner. Avgränsning gjordes genom att en fem år gammal bearbetningslinje för cylinderhuvuden studerades. Genom sortering av data från haverier ur underhållssystemet Maximo från de senaste åren och prioritering genom Paretoprincipen visade det sig att återkommande haverier på kulskruvar finns. Till komponenten finns ett tillståndsbaserat underhåll kopplat, den inspekteras en gång om året. Det är dock sällan som fel på komponenten upptäcks på inspektionen, bara fyra av tjugosju bytta kulskruvar de senaste fem åren är bytta efter anmärkning från inspektion. Genom att kartlägga komponentens haverier på femton verktygsmaskiner och när FU gjorts hittades flera förbättringsmöjligheter. Kostnaden för att byta kulskruv när väl fel uppstått är upp till tio gånger så stor jämfört med att byta den förebyggande. När fel uppstått har det medfört kassationer av producerade detaljer och lång stilleståndstid. Motiv för att införa ett bättre förebyggande underhåll finns därför framför allt i minskade kostnader och ökad tillgänglighet. Företaget rekommenderas att införa ballbarmätning som ett nytt tillståndsbaserat underhåll. Detta för att öka den objektiva kontrollen av mekaniska slitdelar. Mätmetoden är inte helt okänd för företaget och relativt lätt att införa. Den subjektiva kontrollen som görs idag bör göras om för att bättre fånga begynnelse till fel. Kontrollen kräver idag en hel del driftstoppstid vilket gjort att den inte utförts i tid och bör därför kortas ner. Företaget rekommenderas också att undersöka nya metoder för förebyggande underhåll kontinuerligt. Idag finns ingen anställd med uppdraget och för att utveckla underhållet måste företaget hålla sig uppdaterade på nya tekniker. / A company can use different strategies when performing maintenance. One strategy is corrective maintenance where maintenance is carried out after a failure has occurred. Another strategy is preventive maintenance. A combination of the two is often used. The preventive maintenance can be predetermined or condition based. Advantages with the condition based maintenance are e.g. that the replacement of parts can be planned according to observations indicating there’s an increasing risk of failure. When choosing preventive maintenance, the RCM method can be used to determine risk of failure modes and the cause of function failures. Decisions regarding the preventive maintenance should be based on knowledge in new techniques, history of failures and the equipment and competence available. Volvo Cars in Skövde is doing more or less the same preventive maintenance on machine tools regardless of whether it’s a new or old machine. The company is using condition based maintenance on some of the components and units. Mostly it consists of human inspections, a subjective control of the machine’s condition, and spindle vibration analysis. Through interviews it has been determined that new techniques are rarely implemented and that the decided maintenance plan for a machine is rarely changed. The company is aware of the development of new techniques for condition based maintenance and wants to investigate whether it is appropriate to evolve their condition based maintenance on machine tools. The techniques further investigated are measurement with Ball bar, monitoring of process parameters and geometrical verification. To make accurate decisions regarding the implementation of new techniques, a data collection of the history of frequent failures was done. To limit the amount of data a five year old processing line was studied. Data from the maintenance system Maximo was sorted by long failures from the recent years and by prioritizing with the Pareto principle it showed the recurring failures of ball screws. The component do have a condition based maintenance activity today, there is an inspection once a year. However, the inspection is rarely able to predict or find a failure on the ball screw. Four out of twenty-seven ball screws with fault have been changed after inspection over the last five years. By mapping the components failures on fifteen machine tools and when preventive maintenance has been done, several options for improvements were found. The cost of the replacement of a ball screw when a failure has already occurred is as much as ten times the cost of replacement before failure. This is caused by cost of scrap and long down time. A new, improved preventive maintenance task is therefore highly justified. The motif is both reducing the scrap cost related to failure and with increased availability. The company is recommended an investment in Ball bar as a new method for condition based maintenance. It should be used to increase the objective control of the mechanical parts of a machine tool. The method is not totally new for the company and relatively easy to implement. The current subjective control on the machine tools should be revised to increase the probability of finding degradation of functions. Today the activity takes rather long time and has therefore not been done in time, it should be shorter. The company is also recommended to investigate new methods for preventive maintenance continually. Today there is no employee with that mission and to evolve maintenance, the company has to be updated on new techniques.

Face aux nouveaux cadres législatifs ou environnementaux dans lesquels ils doivent évoluer, les systèmes industriels actuels sont, en plus d'être contraints par des exigences classiques de productivité et de cout, sujets au respect de nouvelles exigences relatives à la sûreté, la sécurité ou au développement durable notamment. Pour répondre à ces exigences et améliorer la maitrise des performances de ses systèmes, EDF souhaite faire évoluer sa démarche d'Optimisation de la Maintenance Basée sur la Fiabilité vers une nouvelle méthode. Cette méthode nécessite en autre la proposition d'une approche outillée permettant de quantifier a priori les programmes de maintenance (CMPQ) sur ses systèmes par rapport aux indicateurs de performance attendus (KPIs). Cet outillage fait l'objet de cette thèse financée dans le cadre du GIS 3SGS - projet DEPRADEM 2. Après avoir généralisé les besoins d'EDF en regard de la CMPQ, nous proposons une identification de la connaissance générique nécessaire pour évaluer les KPI. Afin d'aboutir à un outil permettant l'automatisation de ces études de CMPQ, cette connaissance générique est ensuite modélisée sur la base de deux langages : le langage semi-formel SysML capitalisant, par l'intermédiaire de différents diagrammes, la connaissance statique, interactionnelle et comportementale ; et le langage AltaRicaDF, supportant un modèle dynamique permettant d'évaluer les KPIs par simulation stochastique. La création de ce modèle dynamique à partir des différents diagrammes est basée sur un mapping entre les concepts d'intérêt des deux langages. La démarche dans sa globalité est validée à la CMPQ d'un cas d'étude fourni par EDF : le système ARE.

Derrière la grande diversité de ses manifestions, l'entretien des personnes et des biens se révèle être une catégorie juridique originale. Cette notion, en effet, est irréductible à aucune autre, non seulement parce qu'elle obéit à des critères qui lui sont propres, mais aussi parce qu'elle se trouve assortie d'un régime qui lui est spécifique. L'originalité de l'entretien des personnes et des biens procède tout d'abord de son unité notionnelle, découverte par la recherche de sa définition. Qu'il soit accompli à l'égard d'une personne ou d'un bien, l'acte d'entretien a toujours la même cause: le dépérissement de la personne ou du bien. De plus, pour pouvoir être qualifié d'entretien, un acte doit réunir deux critères. Il doit assurer le maintien d'une existence normale et le maintien d'une existence durable.• Ces critères de qualification établissent une frontière assez nette entre l'entretien et les notions qui lui sont voisines, à savoir celles de fournitures d'aliments et de conservation ainsi que celles relatives à la gestion d'un patrimoine et celles de garde et de surveillance. Toutefois, l'originalité de l'entretien des personnes et des biens n'est pas uniquement notionnelle. Suite à la découverte de l'unité de la notion, on pouvait s'attendre à ce que lui réponde une unité de régime. Tel n'est pourtant pas Je cas. Bien qu'étant une notion parfaitement unitaire, l'entretien se singularise en outre par la dualité de son régime qui n'est en rien incompatible avec l'unité de la notion puisque c'est la consistance de cette dernière qui fait que l'acte d'entretien est facultatif ou obligatoire. / No English summary available.

No description available.

The master's thesis deals with maintenance in the theoretical part, this part is describing historical development and individual systems. Then explains concepts of vibro-diagnostics and electro-diagnostics. Further work will focus on complex maintenance systems such as Reliability Centered Maintenance (RCM). The implementation of RCM in the manufacturing company is the subject of a practical part.

This master thesis concerns modern method of TPM used in the production companies for maintenance of machinery. In the theoretical part, general maintenance is first described, as well as the TPM method. There is also described the technical diagnostics, which was emphasized in the practical part in terms of the use of vibrodiagnostics in predictive maintenance. In the practical part there is presented the proposal for introduction of the TPM method at the SMC Industrial Automation s.r.o. in Vyškov.

Surface treatments are often used in the manufacturing industry to change the surface of a product, including its related properties and functions. The occurrence of degradation and corrosion in surface treatment processes can lead to critical breakdowns over time. Critical breakdowns may impair the properties of the products and shorten their service life, which causes increased lead times or additional costs in the form of rework or scrapping.  Prevention of critical breakdowns due to machine component failure requires a carefully selected maintenance policy. Predictive maintenance is used to anticipate equipment failures to allow for maintenance scheduling before component failure. Developing predictive maintenance policies for surface treatment processes is problematic due to the vast number of attributes to consider in modern surface treatment processes. The emergence of smart sensors and big data has led companies to pursue predictive maintenance. A company that strives for predictive maintenance of its surface treatment processes is Seco Tools in Fagersta. The purpose of this master's thesis has been to investigate the occurrence of critical breakdowns and failures in the machine components of the chemical vapor deposition and post-treatment wet blasting processes by mapping the interaction between its respective process variables and their impact on critical breakdowns. The work has been conducted as a Six Sigma project utilizing the problem-solving methodology DMAIC.  Critical breakdowns were investigated combining principal component analysis (PCA), computational fluid dynamics (CFD), and statistical process control (SPC) to create an understanding of the failures in both processes. For both processes, two predictive solutions were created: one short-term solution utilizing existing dashboards and one long-term solution utilizing a PCA model and an Orthogonal Partial Least Squares (OPLS) regression model for batch statistical process control (BSPC). The short-term solutions were verified and implemented during the master's thesis at Seco Tools. Recommendations were given for future implementation of the long-term solutions. In this thesis, insights are shared regarding the applicability of OPLS and Partial Least Squares (PLS) regression models for batch monitoring of the CVD process. We also demonstrate that the prediction of a certain critical breakdown, clogging of the aluminum generator in the CVD process, can be accomplished through the use of SPC. For the wet blasting process, a PCA methodology is suggested to be effective for visualizing breakdowns.

This master thesis has the purpose to analyse and identify smart efficient future solutions within the Maintenance, Repair and Overhaul (MRO) process for aircraft. The efficiency solutions, in form of new technologies and tools, should present a foundation that MRO suppliers can continue to develop to enhance and streamline their maintenance processes. The project was performed as a case study at the aerospace and defense company Saab AB in Linköping, where the company's MRO process was investigated. Through identifying possibilities and alternative technologies available today and in the near future, one continues to have a competitive and future-proof position in the market.  Through an own constructed course of action influenced from established methods, the thesis' purpose and aim was attained. The method was based on authentic approaches for case studies but also inspired by the so-called "Requirement Engineering". The combination of the methods resulted in a precise focus on the relevant subjects, together with a clear structure of the requirements on the technologies to reach a successful implementation. Through a detailed data collection comprised of study visits, interviews, literature studies, market analyses, and document reviews, multiple relevant technologies and requirement-lists for utilization were identified.  To concretize the use and potential improvements with the technologies, the project had the objective to develop a demonstrator with one of the technologies presented. The demonstrator should focus on minimizing the use of paper, which is a common problem among many market actors today. The most promising technology was considered to be a tablet application with an accommodated application. The selection of the tablet solution was based on the motivation that it is a well-established technology and a favorable first step from paperwork.  To conclude this master thesis, a tablet application was developed in Novacura Flow Studio, where the majority of the identified requirements were fulfilled. Beyond the demonstrator, an introduction and analysis of technologies, such as AR-glasses, voice guidance, additive manufacturing, and a digital twin, was presented.

This study reports on language contact phenomena among the Italian-Venetian communities of Anglophone Canada. The analysis perspective is twofold: on one hand it studies language maintenance/attrition comparing two cohorts of migrants, those already well researched who migrated during the period of mass migration (1945-1967) and those who did so in the following four decades (1970-2009). On the other, it investigates language maintenance/attrition taking an intergenerational perspective on three generations of speakers. The corpus used in the analysis is composed of 56 interviews, collected during three months of fieldwork in Canada in 2009. These data were supplemented by 99 questionnaires, which set the background of the analysis, discussing in particular the linguistic habits and attitudes of the community investigated. Given the huge amount of data considered and the mainly quantitative approach taken in this research, two statistical software programs, Taltac and SPSS, were employed to help with the analysis. Another tool, meta-linguistic observation, is also used to broaden the general framework of the study and whenever possible support it with more evidence. The literature on language maintenance/attrition among Italian migrant communities is sizeable; however, there remains room for further investigations. This work, in particular, addresses two major aspects still rarely explored: first, quantifying the decline in heritage language skills on a generational scale, and secondly, comparing the linguistic skills of post-Second World War migrants, on which research has mostly concentrated so far, with those of new waves of migrants. Although this thesis is concerned with a particular geographical and historical framework and the findings are therefore representative of this specific context, the work aims to point to some observations from which generalisation may be possible. By setting side by side these two very distinct cohorts and discussing the new linguistic tendencies in language proficiency among the most recent groups of migrants, research is opened to the new scenarios evolving among Italian communities abroad.