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Melhoria da qualidade no projecto e na fabricação : estudo de caso de uma empresa construtora de autocarrosVieira, Isabel Cristina Martins January 2012 (has links)
Trabalho realizado na CaetanoBus, orient. Francisco José Ferreira Magalhães / Dissertação de mestrado integrado. Mestrado Integrado em Engenharia Metalúrgica e de Materiais. Faculdade de Engenharia. Universidade do Porto. 2012
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Konceptframtagning av inspektionspluggar till flygmotorerRoskvist, Jimmy, Rydell, Richard January 2009 (has links)
<p>This report describes the results of the project "Concept development of jet engine inspection plugs" carried out in the spring of 2008. The work was done at the department of product definition at the company Volvo Aero in Trollhättan. The objective of the work was to develop concepts for a "Volvo-unique" inspection plug. The work is part of Volvo Aero's focus on proprietary (self-developed) technologies. Inspection plugs can be found on virtually all aircraft engines and gas turbines. They are used during inspections with fiber optics done at regular intervals during engine operation. Since the inspection plugs are screwed in and out many times during the life of an engine, it is important that the handling (the assembly and disassembly) is simple. It is also very important that the plugs are properly fixed in position to prevent them from coming off during operation. The focus of the work was to develop proposals on how the assembly and fixing of plugs could be designed to simplify the handling and have adequate and simple function. The procedure during the work was to first study relevant theory and methods that could be used. Then development was carried out according to the first steps of the systematic design methods. These steps include product specifications, concept generation, evaluation and selection of concepts, and development of selected concept. During the implementation, a number of tools and methods, including QFD, FMEA and decision matrices were used. Out of 14 developed concepts, two were chosen for comparison with a leading rival. Both developed concepts turned out to outscore the competitor and the main difference was the cost of production. One of the concepts was considered to have advantages over the other and was consequently chosen for further development. Geometry, manufacturing, materials, sealing and misalignment were the focus areas of the development. CAD models were made of the various design ideas that were identified and one principal inspection plug was recommended for further development.</p>
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Konceptframtagning av inspektionspluggar till flygmotorerRoskvist, Jimmy, Rydell, Richard January 2009 (has links)
This report describes the results of the project "Concept development of jet engine inspection plugs" carried out in the spring of 2008. The work was done at the department of product definition at the company Volvo Aero in Trollhättan. The objective of the work was to develop concepts for a "Volvo-unique" inspection plug. The work is part of Volvo Aero's focus on proprietary (self-developed) technologies. Inspection plugs can be found on virtually all aircraft engines and gas turbines. They are used during inspections with fiber optics done at regular intervals during engine operation. Since the inspection plugs are screwed in and out many times during the life of an engine, it is important that the handling (the assembly and disassembly) is simple. It is also very important that the plugs are properly fixed in position to prevent them from coming off during operation. The focus of the work was to develop proposals on how the assembly and fixing of plugs could be designed to simplify the handling and have adequate and simple function. The procedure during the work was to first study relevant theory and methods that could be used. Then development was carried out according to the first steps of the systematic design methods. These steps include product specifications, concept generation, evaluation and selection of concepts, and development of selected concept. During the implementation, a number of tools and methods, including QFD, FMEA and decision matrices were used. Out of 14 developed concepts, two were chosen for comparison with a leading rival. Both developed concepts turned out to outscore the competitor and the main difference was the cost of production. One of the concepts was considered to have advantages over the other and was consequently chosen for further development. Geometry, manufacturing, materials, sealing and misalignment were the focus areas of the development. CAD models were made of the various design ideas that were identified and one principal inspection plug was recommended for further development.
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Upprättande av underhållsplan för rullkanal LRQ på SKF, gällande pressutrustning : Examensarbete i flygteknikPettersson, Lars January 2010 (has links)
Denna rapport behandlar arbetet kring att ta fram åtgärder för förebyggande underhåll på en kanal för tillverkning av rullar till rullager, vid SKF i Göteborg. Målet har varit att upprätta ett grundläggande underhållsprogram, med fokus främst på operatörsunderhåll, med syftet att få ner antalet oplanerade driftstopp. Upplägget var att först knyta samman den kunskap som fanns samlad på företaget, många av kanalens maskiner var av äldre modell och har funnits i produktionen i många år, varför det visade sig finnas många personer med erfarenhet på dem på olika positioner. Samtal fördes med främst operatörer, tekniker och mekaniker, då det är dessa personer som arbetar närmast och mest med maskinerna, i syfte att isolera de mest frekventa felområdena. Analysen resulterade i en lista med förslag på åtgärder, vilken gicks igenom grundligt med, på maskinerna, kunnig och erfaren personal. Detta ledde till att listan så småningom kom att omfatta till synes relevanta underhållspunkter, med förslag på åtgärd, intervall och utförare. Nästa steg var att gå djupare i komponentnivå på en enstaka maskin, den viktigaste och mest kritiska på kanalen, nämligen själva pressen, med vilken man pressar råmaterial, kallat kuts, till rullar. Vilka efter slipning/polering monteras tillsammans med ytter- och innerring till att bilda ett komplett rullager. Pressen var av modell äldre, från någon gång under 70-talet, en tid då man hade en helt annan underhållsfilosofi, vilket för med sig att underlag för förebyggande underhåll är bristfällig i sin natur, eller saknas helt. Analysen utfördes i form av en så kallad RCM-analys, en process där man bryter ner maskinen på komponentnivå och genom en FMEA-kategorisering avgör huruvida komponenten är kritisk på någon av punkterna; tillgänglighet, produktivitet, kvalitet, säkerhet, miljö eller ekonomi. Utifrån detta tar man fram åtgärder till de kritiska komponenterna. Tillsammans med punkterna från det första steget bildades en ganska omfattande lista med underhållsåtgärder, vilket innefattade åtgärd, intervall och utförare. Sista steget innan implementering var att sammanställa åtgärdslistan i ett av företaget standardiserat format, vilket innebär att man vill kunna skriva ut åtgärderna tillsammans med bilder för att sätta i pärmar och förvara i kanalen, för lätt åtkomst för kanalens personal. Själva slutresultatet, tillika underhållsprogrammet, återfinns i bilaga C och D i denna rapport.
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A Literature Review on Risk Analysis of Production Location DecisionsDadpouri, Mohammad, Nunna, Kiran January 2011 (has links)
This report is the result of a master thesis with a focus on risk analysis of production location decisions. The project is a part of “PROLOC-manufacturing footprint during the product’s life cycle”. The main aim of this thesis is to point out how current applicable risk analysis techniques evaluate the risks involved in production location decisions and then underline the most important risks involved in production location decisions and elicit strengths and weaknesses of these methods.A systematic review of literature with a focus on journal papers of risk analysis and production fields is conducted by using the content analysis and coding technique. The current risk analysis techniques identified are failure mode and effects analysis (FMEA), life cycle cost (LCC) analysis, and system based techniques like multiobjective analysis, decision tree analysis, and analytic hierarchy process (AHP). In addition two identified frameworks of foreign direct investment (FDI) and international production are the research fields that have contributed extensively in identifying various risks of production location decisions.Having reviewed the literature, it is realized that majority of companies take a short sighted vision in choosing production location and consider just cost based issues like cheaper raw material and low labour cost in some countries and simply ignore uncertainties that can be sources of political, economic, social, competitive, and seismic risks. Low cost countries are usually situated in politically instable areas that can cause long production halts or expropriation. Political risk is mainly identified in FDI literature and is usually triggered by a political turmoil, coup d’état, or revolution. On the other hand cheap labour does not necessarily mean decrease in costs and might bring about quality issues and damage company prestige among customers which results in time and monetary loss. Currency exchange and inflation in costs often causes the initial forecast and cost analysis go wrong. Supply risks are because of disruption of ties with raw material or part suppliers in home country and might result in risk of misuse by new suppliers or partners. Also the seismic risk is introduced as a separate category of risks of production location decisions which can be considered a matter of more investigation and requires further research.The study also presents a review of strengths and weaknesses of existing risk analysis techniques of production location decisions. The lack of consistency, vagueness of information, unfamiliarity with design to cost concept are among the major weaknesses of risk analysis techniques of production location decisions. The study concludes with the fact that just considering the cost oriented factors like cheap labour and raw material by production companies exposed them to various risk and might make the whole investment in vain. Suggestions for further study on techniques and risks of production location decisions are also proposed.
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Further Development of a Docking Station : Redesign of MagniLink S Docking Station at LVI Low Vision InternationalJohansson, Tim, Nilsson, Pontus January 2015 (has links)
The purpose of this work is to evaluate how a docking station can be more future proof, environmentally friendly and satisfy the customers’ needs more. The docking station in focus of this project is owned by LVI, and used with one of their cameras MagniLink S. When comparing the results of the new docking station and the current docking station, the new docking station is more future proof, environmentally friendly and satisfies the customers’ needs more. In the end it is established that following steps should be followed during the development of a docking station: - Make sure that the cables are reliably fastened into the docking station and that the connectors can handle the docking force. - Design to use more material with lower environmental impact and ensure that the material fulfils the product requirements and objectives. Use as small amount of material as possible. - Prioritize the customers’ expressed and unexpressed needs as one of the highest priorities during the development process.
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Weight Reduction of Reach StackerEkdahl Norling, Linda January 2014 (has links)
The report is about reducing the Eigen weight of a reach stacker in order to obtain decreased fuel consumption. The detail the product development treats is the telescopic boom. By using steel of higher strength the dimension can be decreased, which in turn results in a reduced weight. Suitable steel for the application might be the high strength structural steel of designation S690QL. With support of calculations and CAD simulations the possible weight reduction is assumed to amount to 28%.
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Reliability improvement of railway infrastructureJidayi, Yakubu Mara 03 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The railway transportation system is fundamental in sustaining the economic activities of a
country, by providing a safe, reliable and relatively affordable means of transporting people and
goods; hence, the need to ensure its ongoing reliability is of paramount importance. The principle
and applications of rail reliability have been reviewed, and reliability improvement in rail
infrastructure has been investigated using failure mode and effect analysis (FMEA).
Reliability improvement is a continuous process that is geared to meeting dynamic changes in
operation and stakeholders’ expectations. Recently, growth has occurred in the amount of rail
transport traffic utilisation undertaken, together with the degradation of the infrastructure
involved. Such deterioration has amplified the operating risks, leading to an inadequacy in rail
track maintenance and inspection that should have kept abreast with the changes. The result has
been increased rail failures, and subsequent derailments.
A case study of the Passenger Rail Agency of South Africa (PRASA) Metrorail maintenance
policy was reviewed to evaluate its maintenance strategy and identifying the potential critical
failure modes, so as to be able to recommend improvement of its reliability, and, thus, its
availability. On the basis of the case study of PRASA Metrorail maintenance strategy and its
performance, it is recommended that PRASA Metrorail change its maintenance policy through
employing a cluster maintenance strategy for each depot. / AFRIKAANSE OPSOMMING: Die spoorwegvervoerstelsel is fundamenteel om die ekonomiese bedrywighede van ’n land te
ondersteun deur die voorsiening van ’n veilige, betroubare en betreklik bekostigbare manier om
mense en goedere te vervoer. Dus is dit van die allergrootste belang om die voortgesette
betroubaarheid daarvan te verseker. Die beginsels en toepassings van spoorbetroubaarheid is
hersien en die betroubaarheidsverbetering van spoorinfrastruktuur met behulp van foutmodus-eneffekontleding
(“FMEA”) ondersoek.
Betroubaarheidsverbetering is ’n voortdurende proses om tred te hou met dinamiese
bedryfsveranderinge sowel as verskuiwings in belanghebbendes se verwagtinge. Die hoeveelheid
spoorvervoerverkeer het onlangs beduidend toegeneem, terwyl die betrokke infrastruktuur
agteruitgegaan het. Dié agteruitgang het die bedryfsrisiko’s verhoog, en lei tot ontoereikende
spoorweginstandhouding en -inspeksie, wat veronderstel was om met die veranderinge tred te
gehou het. Dit gee aanleiding tot ’n toename in spoorwegfoute en gevolglike ontsporing.
’n Gevallestudie is van die instandhoudingsbeleid van die Passasierspooragentskap van Suid-
Afrika (PRASA) Metrorail onderneem om dié organisasie se instandhoudingstrategie te
beoordeel en die moontlike kritieke foutmodusse te bepaal. Die doel hiermee was om
verbeteringe in stelselbetroubaarheid en dus ook stelselbeskikbaarheid voor te stel. Op grond van
die gevallestudie van die PRASA Metrorail-instandhoudingstrategie en -prestasie, word daar
aanbeveel dat PRASA Metrorail sy instandhoudingsbeleid verander deur ’n
klusterinstandhoudingsplan vir elke depot in werking te stel.
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Development of a maintenance plan for the STEPWISE project at Swerea MEFOSHassabelnaby, Aly January 2018 (has links)
Process plants come with a wide variety of engineering challenges. Each process has uniqueoperating conditions that require careful operation and maintenance programs to keep the process equipment in a condition that is safe for operation. A pilot-scale plant was built in Luleå to demonstrate the possibility of carbon dioxide removal from blast furnace gas usingthe Sorption Enhanced Water Gas Shift (SEWGS) technology. One of the challenges facingthe SEWGS pilot plant was the lack of a maintenance plan which was the motivation for this thesis. The aim of this thesis was to create a maintenance plan for the SEWGS pilot plant. Studying the process conditions of the pilot plant was the starting point since an understanding of the unique operating conditions was necessary for creating a maintenance plan for the pilot plant’s equipment. The Reliability-centered maintenance (RCM) method was chosen to create the maintenance plan. The study began with determining the objectives and contents of the analysis. The next step was a functional failure analysis in the form of a Failure Mode and Effect Criticality Analysis (FMECA) covering all the equipment in the plant. Afterwards the failure consequences were assessed based on a criticality assessment matrix to determine which equipment necessitate the performance of maintenance activities. The maintenance plan was created based upon the criticality of the equipment and the selected maintenance activities were based on the recommendations of manufacturers. The failure analysis found that the blast furnace gas compressor is the most critical for the process. The boiler and superheater have been found to be highly critical due to the dangerous safety consequences of their failure. In addition, all pressure safety valves have been found to be highly critical due to the hidden nature of their failure. The maintenance plan addresses these critical items and other less critical items while some non-critical items have been removed from the plan due to the negligible consequences of their failure.
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Proposta de análise quantitativa de confiabilidade a partir de dados qualitativos provenientes da FMEAGuzzon, Samanta de Oliveira January 2009 (has links)
Este trabalho apresenta um método de análise de confiabilidade de sistemas novos em desenvolvimento, no qual se utiliza como referência dados predominantemente qualitativos. O método proposto está organizado em três fases, as quais são subdivididas em etapas que constituem as atividades a serem realizadas. A primeira fase é a análise FMEA, que visa definir e identificar falhas potenciais do sistema ainda em seus estágios iniciais de conceituação e projeto. A segunda fase é a análise de confiabilidade, que tem como objetivo gerar dados quantitativos para uma análise aprimorada da confiabilidade do sistema a partir de dados qualitativos coletados na fase da análise FMEA. A terceira fase consiste na análise comparativa e visa, além de comparar os resultados obtidos previamente, propor uma forma de integração destes. O método proposto foi aplicado em dois sistemas principais de um sistema de transporte sobre trilhos: o sistema de propulsão e o sistema de controle. Com o intuito de integrar as duas técnicas, propôs-se uma nova forma de calcular o risco, denominado RPNI, que leva em consideração o índice de severidade, a probabilidade de ocorrência, a probabilidade de detecção e o índice de impacto. A partir desse valor, foi então possível determinar os componentes considerados prioritários para os sistemas e propor as medidas cabíveis, tendo em vista as metas de segurança e a confiabilidade do sistema em desenvolvimento. / This work presents a method for the reliability analysis of a new system under development, which uses qualitative data as predominant reference. The proposed method is organized in three phases, which are subdivided in activities to be accomplished. The first phase employs the FMEA to define and identify potential failures in the early stages of conceptualization and system design. The second phase contemplates a mathematical reliability analysis, providing quantitative data for an enhanced analysis of system reliability from qualitative data collected at the first phase. The third phase, named comparative analysis, compares the previous results and proposes an integrated prioritization. The proposed method was applied in two major systems of a transportation system on guideways: the propulsion and the control systems. In order to integrate the FMEA and the mathematical analysis, a different form to calculate the risk, named RPNI, was proposed, which considers the severity index, occurrence probability, detection probability and the impact index. Using the RPNI, it was possible to determine system priority components and to propose appropriate measures to increase the safety and reliability goals of the system under development.
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