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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Water Drop Tribology of Graphene and Polymer Nanocomposites

Cox, Paris 16 September 2013 (has links)
Basic physics teaches us that the frictional force (lateral force) needed to move objects on surfaces are proportional to load (normal force) – Amonton’s Laws. In tribology, this force is proportional to contact area, whereas Amonton is just a special case for contact area scaling with load. Such established laws do not seem to apply to small drops on flat, smooth surfaces in which frictional forces have an inverse relation to contact area and have time component prior to movement. Such phenomena can be explained by Shanahan-deGennes were intermolecular forces are considered for a deformed surface. Graphene is a special case where no time component is observed and frictional forces are attributed to its chemical homogeneity and stability. In the second part of this thesis, graphene is considered as nanofiller to build up polymer nanocomposites via Layer by Layer (LbL). Graphene Nanoribbons derived from multi-walled carbon nanotubes (MWCNT) offers a special case for thermoplastic polyurethane nanocomposites in that of thermally activated twisting morphology influences nanocomposite properties. Finally an electric field driven transdermal hydrogel drug delivery device has been demonstrated by just using CNTs, polyvinyl-borax gel and a CNT membrane
2

Implementering av TPU : En fallstudie om implementeringen av TPU på ABB Cewe-Control i Nyköping

Månsson, Anders January 2008 (has links)
För att svenska företag ska kunna konkurrera med företag som har produktion i lågkostnadsländer måste företagen bedriva en effektivare produktion.Syftet med totalt produktivt underhåll (TPU) är att öka företagets lönsamhet genom att höja produktiviteten. TPU är ett arbetssätt där alla medarbetare ska engageras för att minimera störningar och haverier så att utrustningseffektiviteten kan höjas. Syftet med rapporten är att utvärdera implementeringen av TPU på ABB Cewe-Control i Nyköping och ge rekommendationer för den fortsatta implementeringen. Som grund för analys och slutsats har en fallstudie på ett pilotavsnitt genomförts. Fallstudien byggs upp till största delen av kvalitativ data i form av deltagande observationer, enkäter och intervjuer. Ledningens engagemang är den mest centrala faktorn i implementeringen av TPU. Produktionsledningen på ABB Cewe-Control måste tydligare visa engagemanget i aktiva handlingar för att en förändring ska kunna ske. Resultatet från fallstudien visar på att både medarbetarnas och produktionsledningens engagemang måste höjas för att verksamheten ska kunna utvecklas. För att det framtida arbetet inte heller ska drabbas av onödiga konflikter eller irritation är det viktigt att tydliggöra ansvar och roller vid implementeringen av TPU. Fallstudien har också visat på att utbildningen under implementeringen inte har varit tillräcklig. Ordentlig utbildningen behövs för att TPU-arbetet ska kunna bedrivas på ett effektivt sätt och för att höja motivationen hos medarbetarna. Den förbättringsverksamhet som tidigare har bedrivits inom ramarna för verksamhetsutveckling (VU) är en mycket bra grund för förbättringsarbetet i TPU. Det finns ingen anledning till att inte fortsätta med förbättringsverksamheten enligt VU eftersom det är inarbetat i verksamheten och då VU så tydligt kopplar samman gruppernas arbete med företagets strategiska mål. / If Swedish companies are to compete with companies in low-cost countries they have to achieve a more efficient production. The purpose of Total Productivity Maintenance (TPM) is to increase the company's profitability by increasing the productivity. TPM is a method that involves all employees and aims to prevent failures in order to increase the availability of existing equipment. The aim of this paper is to evaluate the implementation process of TPM and give recommendations for the further implementation process. The conclusion and the analysis are based on a case study done at a production department at ABB Cewe-Controls facilities in Nyköping. The case study consists mainly of qualitative data from participation observations, surveys and interviews. Commitment of the management is a key factor in the implementation process of TPM. The management of ABB Cewe-Control need to demonstrate their commitment in order for a change to happen. The case study shows that the commitment of both employee and management must be raised if the implementation process is to be successful. To avoid unnecessary conflicts or irritation in the further implementation process it is important to clarify responsibilities and roles in the implementation of TPU. The case study has also shown that the training during the implementation process has not been sufficient. Proper training is needed to be able to conduct the implementation process of TPM in an effective manner. Proper training is also needed to raise the motivation of the staff. Business Development is ABB’s methodology for the improvement work in the company. Business Development is a well-known concept in the organisation and has a well-defined connection with the company's strategic objectives. Because of this there is no reason why the improvement work and how it has been done should change. Business Development is a good foundation for the implementation of TPM and the improvement work in the future.
3

Implementering av TPU : En fallstudie om implementeringen av TPU på ABB Cewe-Control i Nyköping

Månsson, Anders January 2008 (has links)
<p>För att svenska företag ska kunna konkurrera med företag som har produktion i lågkostnadsländer måste företagen bedriva en effektivare produktion.Syftet med totalt produktivt underhåll (TPU) är att öka företagets lönsamhet genom att höja produktiviteten. TPU är ett arbetssätt där alla medarbetare ska engageras för att minimera störningar och haverier så att utrustningseffektiviteten kan höjas.</p><p>Syftet med rapporten är att utvärdera implementeringen av TPU på ABB Cewe-Control i Nyköping och ge rekommendationer för den fortsatta implementeringen. Som grund för analys och slutsats har en fallstudie på ett pilotavsnitt genomförts. Fallstudien byggs upp till största delen av kvalitativ data i form av deltagande observationer, enkäter och intervjuer.</p><p>Ledningens engagemang är den mest centrala faktorn i implementeringen av TPU. Produktionsledningen på ABB Cewe-Control måste tydligare visa engagemanget i aktiva handlingar för att en förändring ska kunna ske. Resultatet från fallstudien visar på att både medarbetarnas och produktionsledningens engagemang måste höjas för att verksamheten ska kunna utvecklas. För att det framtida arbetet inte heller ska drabbas av onödiga konflikter eller irritation är det viktigt att tydliggöra ansvar och roller vid implementeringen av TPU.</p><p>Fallstudien har också visat på att utbildningen under implementeringen inte har varit tillräcklig. Ordentlig utbildningen behövs för att TPU-arbetet ska kunna bedrivas på ett effektivt sätt och för att höja motivationen hos medarbetarna. Den förbättringsverksamhet som tidigare har bedrivits inom ramarna för verksamhetsutveckling (VU) är en mycket bra grund för förbättringsarbetet i TPU. Det finns ingen anledning till att inte fortsätta med förbättringsverksamheten enligt VU eftersom det är inarbetat i verksamheten och då VU så tydligt kopplar samman gruppernas arbete med företagets strategiska mål.</p> / <p>If Swedish companies are to compete with companies in low-cost countries they have to achieve a more efficient production. The purpose of Total Productivity Maintenance (TPM) is to increase the company's profitability by increasing the productivity. TPM is a method that involves all employees and aims to prevent failures in order to increase the availability of existing equipment.</p><p>The aim of this paper is to evaluate the implementation process of TPM and give recommendations for the further implementation process. The conclusion and the analysis are based on a case study done at a production department at ABB Cewe-Controls facilities in Nyköping. The case study consists mainly of qualitative data from participation observations, surveys and interviews.</p><p>Commitment of the management is a key factor in the implementation process of TPM. The management of ABB Cewe-Control need to demonstrate their commitment in order for a change to happen. The case study shows that the commitment of both employee and management must be raised if the implementation process is to be successful. To avoid unnecessary conflicts or irritation in the further implementation process it is important to clarify responsibilities and roles in the implementation of TPU.</p><p>The case study has also shown that the training during the implementation process has not been sufficient. Proper training is needed to be able to conduct the implementation process of TPM in an effective manner. Proper training is also needed to raise the motivation of the staff.</p><p>Business Development is ABB’s methodology for the improvement work in the company. Business Development is a well-known concept in the organisation and has a well-defined connection with the company's strategic objectives. Because of this there is no reason why the improvement work and how it has been done should change. Business Development is a good foundation for the implementation of TPM and the improvement work in the future.</p>
4

Framtagning av förebyggande underhållsplan : På tomgodsförsörjningen av rullpallar på Arla Foods Jönköping

Dinh, Minh Thu, Makaraan, Hassan January 2016 (has links)
Strävan om en större konkurrenskraft har medfört förändringar inom modern produktion där det sker en övergång från arbetskraftsberoende produktion till en ökad automatisering av produktionsanläggningar. En ökning av automatiseringar i samband med teknikutveckling har medfört att produktionsutrustningar har blivit mer avancerade och komplicerade att underhålla. Förändringarna har medfört större krav på driftsäkerheten hos produktionsutrustningar för att bemöta kundkrav samt bibehålla konkurrenskraft. Utförandet av ett effektivt underhållsarbete har blivit en viktig faktor för uppnå en driftsäker produktionsanläggning. I Arla Foods Jönköpings mejeri tillämpas både operatörs- och specialistunderhåll på produktionen där mätningar av utrustningar genomförs och förebyggande underhållsplan har utformats. Tomgodsförsörjningen, som förser tomma lastbärare till förpackningsmaskinerna och kyllagret, har däremot ingen underhållsplan, utan det tillämpas enbart akuta underhållsarbeten. Studiens syfte har varit att framställa en förebyggande underhållsplan för tomgodsförsörjningen av rullpallar. Detta har skett parallellt med en störningsanalys där störningar kartlades och därefter utformades åtgärdsförslag. All data införskaffades på Arla Foods mejeri i Jönköping, där metoderna som utnyttjades var observationer, intervjuer, workshops samt dokumentstudier. Dessutom utfördes litteraturstudier, för att ge en teoretisk grund till studien, som behandlar grundläggande underhålls principer och verksamhetsutvecklingskonceptet Total Produktivt Underhåll, TPU. Analysen omfattar en sammanställning av störningar, med hjälp av ett paretodiagram, där de störningar som påverkar försörjningssystemet mest kunde identifieras. Analysen påvisade att 49,3 procent av alla störningar berodde på att rullpallarna fastnade i kurvor samt att defekta rullpallar kom igenom kontroller och orsakade stopp i försörjningssystemet. Dessutom gjordes en analys av det nuvarande underhållsarbetet och hur en utebliven underhållsplan påverkar försörjningssystemet. Utifrån analysen utformades förbättringsåtgärder för de två mest återkommande störningarna samt en FU-plan för försörjningssystemet. Med hjälp av litteraturstudier, underhållspersonalens kompetenser samt leverantörernas underhållsguide har en FU-plan kunnat utformas, där vikt lades i att inte skapa en främmande arbetsmetod. Då hela produktionen arbetar med RIS-tavlor ansågs det som en lämplig arbetsmetod då personalen känner igen och arbetar efter metoden i andra avdelningar. Underhållsplanen består av styrkort, RIS-kort, med instruktioner för varje område och ska även fungera som en checklista för att underhållsarbetet ska ske i rätt tid. En ansvarsfördelning av underhållsarbetet har gjorts som förenklar att underhållsplanen fullföljs. RIS-tavlorna medför att felrapporteringar sker på ett korrekt sätt samt fördelar ansvar och möjliggör dokumentering av utförda reparationer. Vidare rekommenderas Arla Foods Jönköping att integrera den nyutvecklade underhållsplanen i affärssystemet SAP, som underhållsavdelningen arbetar med i dagsläget för att utföra förebyggande underhållsarbete på förpackningsmaskinerna. Dessutom bör en implementering av TPU genomföras i hela organisationen, där den nyutvecklade underhållsplanen anses vara en grund, för att åstadkomma störningsfri produktion med hjälp av ett strukturerat arbetssätt och skapa ett engagemang i organisationen som arbetar tillsammans för ett arbete med ständiga förbättringar. På lång sikt bör det även övervägas att rekonstruera rullpallsbanorna och skapa rakare transportbanor för att undvika kurvor och störningarna de medför. / The pursuit for a greater competitiveness has brought changes in modern production, where there is an ongoing transition from labour-dependent production to an increased automation in production plants. The increase of automation and the advance of technology has meant that production equipment has become more sophisticated and complicated to maintain. The changes have brought greater demands on the dependability of production equipment in order to meet customer requirements and also maintain competitiveness. The execution of an effective maintenance has become an important factor in order to achieve a dependable production plant. Arla Foods Jönköping’s dairy plant works with both operator and specialist maintenance, where measurement on equipment are carried out and preventive maintenance plan has been developed. On the other hand, the empty-packaging-supplying system, which supplies empty cargo carriers to the packaging machines and to the cold storage warehouse, lacks a maintenance plan and therefore only emergency maintenance work are applied. The purpose of this study has been to develop a preventive maintenance plan for the empty-packaging-supplying system of rolltainers. This has taken alongside an interference analysis where interferences were mapped and then a proposal for action was devised. All data was obtained in Arla Foods Jönköping’s dairy plant, where the methods that were used are observations, interviews, workshops and document studies. Literature studies, that treats basic maintenance principles and Total Productive Management, TPM, where also performed in order to provide a theoretical basis for the study. The analysis covers a compilation of interferences, through a Pareto chart, where those interferences which affected the supplying system most could be identified. The analysis showed that 49,3 percent of all the interferences was due to rolltainers that got stuck on curves and defective rolltainers that went through controls and caused a stop of the supplying system. An analysis was also made of the current maintenance work and how the lack of a maintenance plan affects the supplying system. Based on the analysis, a proposal for action was devised for the two most prevalent interferences and a preventive maintenance plan for the supplying system was developed. With the help of literature studies, maintenance staffs competencies and the suppliers maintenance guide, a preventive maintenance plan was developed, where great emphasis was put on to not introduce an alien working method. Since the whole production works with RIS-boards and the personnel are familiar with them, it was viewed as a suitable working method. The maintenance plan consists of scorecards, RIS-cards, with instructions for each area, and will also serve as a checklist for the maintenance work to take place at the right time. In order for the maintenance work to be fulfilled a delegation of responsibility for the maintenance work has been made. The RIS-boards enables error reports to be made in a proper way, delegate responsibility and enables documentations of performed reparations. Furthermore, Arla Foods Jönköping is recommended to integrate the newly developed maintenance plan with SAP, which is an enterprise resource planning software, which the maintenance department is currently working with to perform preventive maintenance on the packaging machines. Also, an implementation of TPM should be applied throughout the whole organization, where the newly developed maintenance plan is considered to be a basis for achieving interference-free production through a structured approach and create a commitment in the organization to work together for continuous improvement efforts. In the long term, consideration should be given to reconstruct the rolltainer tracks and create more direct transportation tracks to avoid curves and the interferences they create.
5

Automatiserad utläggning och upptagning av temporära väglinjer med tillhörande materialvalundersökning / Automated pick and placement of temporary road-lines with associated material selection analysis

Ågren, Ellen, Andersson, Emanuel, Kardell, Kasper January 2019 (has links)
Uppdragsgivaren för projektet har varit AstaZero, de specialiserar sig på validering och forskning av aktiva säkerhetssystem. Ett pålitligt, aktivt säkerhetssystem är ett väldigt effektivt verktyg och kommer att spela en stor roll för att minska antal olyckor i trafiken världen över. Tillförlitligheten på systemen bygger på kvalitet och kvantitet av simuleringsmiljöer av trafiksituationer som utförs på särskilda testbanor, bland annat AstaZeros anläggning i Hällered. Kandidatuppsatsen har vart inriktad på att ta fram ett koncept för ned samt upptagning av de temporära väglinjerna som används för uppbyggnad av olika simuleringsmiljöer med en tillhörande materialvalsanalys av linjerna. I dagsläget är uppbyggnaden av dessa trafiksituationer en resurskrävande process då det sker manuellt och de temporära väglinjerna som används blir emellanåt påkörda. Det leder till att nuvarande material för väglinjerna blir deformerat och obrukbart för framtida simuleringar. Målet med uppsatsen är att komma fram till en automatiserad maskin för applikationen samt en materialundersökning för att ersätta de befintliga linjerna. Examensarbetet innehåller de aktuella faserna för uppdraget från den traditionella produktutvecklingsprocessen. Koncept har tagits fram ur en idégenereringprocess och vidare evaluering av koncepten har gjorts i så kallade värderingsmatriser. Därefter skapades 3D skisser för det mest gynnsamma alternativet. Selektering av lämpliga material för ändamålet har skett via ett materialvalsprogram samt litteraturgranskning av vetenskapliga artiklar. De material som granskningen mynnade ut i har tagits fram i högskolans laborationsavdelning. Därefter testades utvalda mekaniska egenskaper för att validera dess reabilitet mot de befintliga databladen som finns till vårt förfogande. Arbetet avslutas med förslag på vidare forskning samt förädling av koncept och material. / The client for the project has been AstaZero who specializes in validation and research of active safety systems. A reliable active safety system is a very effective tool and will play a major role in reducing the number of traffic accidents worldwide. The reliability of the systems is based on the quality and quantity of simulation environments of traffic situations performed on specific test tracks, including AstaZero's facility in Hällered. This bachelor thesis has been focused on developing a concept for pick and placement of the temporary road lines used for the construction of different simulation environments, with an associated material selection analysis of the lines. At the present, the build-up is a resource-intensive process as it is performed manually and the temporary road-lines that AstaZero uses are sometimes hit. This leads to the current material for the road lines being deformed and unusable for future simulations. The aim of this thesis is to conceptualize an automated machine for the application and to do a materal analysis to eventually replace the existing lines. The project contains the phases relevant for the assignment from the traditional product development process. Concepts have been developed from an idea generation process and further evaluation of the concepts has been done in valuation matrices. 3D-drawings were created for the most favorable option. Selection of suitable materials for the purpose has been done via a material selection program and literature review of scientific articles. The materials that the examination resulted in have been produced in the university's laboratory department. Subsequently, selected mechanical properties were tested to validate its reliability to the existing data sheets available at our disposal. The work concludes with proposals for further research and refinement of chosen concept.
6

Desempenho de poliuretanos termoplásticos particulados como adesivo para indústria calçadista

Bockorny, Geovana de Avila January 2016 (has links)
Elastômeros termoplásticos têm sido largamente empregados como adesivos hot melt em diferentes setores da indústria. Neste trabalho foram estudados dois copolímeros em bloco de poliuretano na forma particulada, base poliéster (TPU1) e policaprolactona (TPU2), com o objetivo de avaliar o desempenho dos mesmos como adesivos particulados. Foram preparadas diferentes composições dos TPUs com aditivos de policarbodiimida (A), resina hidrocarbônica (B) e poliisocianato (C). Os TPUs aditivados em diferentes composições foram avaliados por termogravimetria (TGA) e calorimetria diferencial de varredura (DSC) e quanto à resistência da colagem. A cinética de cristalização dos TPUs particulados puros e aditivados em diferentes isotermas foi acompanhada por DSC. Os adesivos TPU1 apresentaram velocidade de cristalização mais lenta, com exceção do TPU1 contendo os aditivos A e B (TPU1AB). Os adesivos TPU2 apresentaram taxa de cristalização maior somente quando aditivado com mistura de aditivos (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). O expoente de Avrami (n) foi inferior para os TPUs aditivados, o que sugere a ocorrência de alteração no tipo de nucleação e geometria de crescimento dos cristalitos. Os TPU1 (poliéster) e TPU2 (policaprolactona) apresentaram perfil de degradação térmica diferenciados devido a diferenças na estrutura química dos mesmos. Os adesivos TPU2 apresentaram valores de resistência mecânica mais elevados que os TPU1, em colagens de substratos de PVC. Os adesivos com maiores valores de resistência (TPU1A e TPU2A) foram extrusados e micronizados para uso como tal. O adesivo TPU1A micronizado apresentou aumento da resistência mecânica. As colagens com os adesivos TPU1 e TPU2 apresentaram falha coesiva e as composições TPU1B e TPU2AC demonstraram falha coesiva e adesiva em ensaio de tração. O processamento dos adesivos TPU1 por tratamento de plasma favoreceu um incremento dos valores de resistência de colagens em substratos de PVC. / Thermoplastic elastomers have widely been used as hot melt adhesives in different industry sectors. In this paper were studied two polyurethane block copolymers in particulate form, based polyester (TPU1) and polycaprolactone (TPU2), in order to evaluate their performance as adhesives. Different compositions of TPUs were prepared with polycarbodiimide (A), hydrocarbon resin (B) and polyisocyanate (C) additives. The TPUs with additives in different compositions were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) and by the bond strength. The kinetics crystallization of pure and additivated TPUs at different isotherms were followed by DSC. The TPU1 adhesives showed lower crystallization rate, except the TPU1 with both A and B additives (TPU1AB). The TPU2 adhesives showed higher crystallization rate only when formulated with mixture of additives (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). The Avrami exponent (n) was lower for the TPUs containing additives, which suggests changes in the nucleation type and crystallites growth geometry. The thermal degradation profile of both TPU1 (polyester) and TPU2 (polycaprolactone) adhesives were quite different due to chemical differences. The TPU2 adhesives showed higher strength values than TPU1s on PVC substrates. The adhesives with higher bond strength (TPU1A and TPU2A) were extruded and micronized, and the TPU1A adhesive showed improved bonding property. The TPU1 and TPU2 adhesives on PVC collages showed cohesive failure and the TPU1B and TPU2AC compositions showed cohesive and adhesive failure under tension test. The adhesive plasma treatment promoted a bonding increasing of TPU1 on PVC substrates.
7

Modeling and Control of Electromechanical Actuators for Heavy Vehicle Applications

Pettersson, Alexander, Storm, Patrik January 2012 (has links)
The possibility to develop control systems for electromechanical actuators at Scania is studied, in particular the focus is on how to exchange the intelligent actuators used today with dumb ones. An intelligent actuator contains its own control electronics and computational power, bought as a unit from suppliers by Scania and controlled via the CAN bus. A dumb actuator contains no means of controlling itself and its I/O is the motor’s power pins. Intelligent actuators tend to have limited control performance, time delays and poor diagnose systems, along with durability issues. A dumb actuator could have the benefit of avoiding these disadvantages if the system is designed within the company. A literature study concerning the different types of electrical motors available and their control methods is performed, the most suitable for use in a heavy vehicle is deemed the brushless DC motor, BLDC. An intelligent throttle is chosen for a case study and has its control electronics stripped and replaced with new sensor- and control cards. The case study is used to investigate the possibilities and difficulties of this design process. A simulation model is developed for the electronics, motor and the attached mechanical system. With the aid of this model a controller architecture is designed, consisting of PI controllers with feed-forward and torque compensation for nonlinearities. The developed controller architecture is tested and in theory it can compete with the intelligent throttle’s performance. The model is also adapted to allow for code generation. The simulation model is used to study some common electrical faults that can effect the system and the possibilities for diagnosis and fault-remedial actions. The hardware prototype system shows that a current controller is necessary in the control architecture to achieve decent performance and the prototype is developed in such a way as to make future studies possible. The conclusion of the thesis is that Scania would be able to design control systems for dumb actuators, at least from a technical perspective. However more studies, from an economical point of view, will be necessary.
8

Plan för implementering av strukturerat underhållsarbete på Valmet ABs gjuteri i Karlstad

Åstrand, Leon January 2014 (has links)
Rapporten handlar om att sätta upp en plan för implementering av ett mer strukturerat underhållsarbete på Valmet ABs gjuteri i Karlstad. Arbetet görs i kursen examensarbete för högskoleingenjörsexamen i maskinteknik på Karlstads universitet under våren 2014. Valmet har nyligen köpt upp gjuteriet på Lamberget i Karlstad. Där är det ett mycket eftersatt underhåll och finns i nuläget inte någon bra struktur på hur de arbetar med underhåll. Underhållsverksamheten är i behov av att systematiseras och integreras i Valmets övriga underhållsorganisation. Syftet med arbetet är således att utarbeta en plan för att strukturera underhållet på Valmets gjuteri i Karlstad. Arbetet är indelat i tre faser. - Nulägesanalys genom dels intervjuer av underhållspersonal samt kartläggning av utrustning - Skapa en målbild över hur man vill arbeta med underhåll, genom studiebesök hos andra liknande verksamheter, diskussioner med ledningen samt litteraturstudier. - Upprättande av plan för hur man ska ta sig dit. Vilka aktiviteter som skall utföras samt i vilken ordning, där bland annat lämpliga mätetal ska tas fram. Arbetet är baserat på metodiken TPM (total productive maintenance), det handlar dock inte om ett fullständigt införande av TPM utan begränsat till valda delar. Utifrån intervjuer med underhållspersonalen på gjuteriet samt observationsstudier och en kartläggning av maskinparken har en nulägesanalys gjorts. Denna nulägesanalys har visat de problem och utmaningar som finns på underhållsavdelningen på gjuteriet. En målbild över hur man vill arbeta med underhåll på gjuteriet har ritats upp utifrån de studiebesök samt intervjuer med personal i ledningen. Det mest vitala som framkommit i denna fas är hur viktigt ledningens engagemang är för att kunna genomföra ett förändringsarbete, samt hur viktigt det är med en bra kommunikation både mellan de olika avdelningarna, men också inom gruppen. Med hjälp av de två ovanstående faserna samt den teori som bearbetats under projektet har en plan upprättats för ett mer strukturerat underhållsarbete. Planen innefattar 12 punkter som behandlar de aktiviteter som bör implementeras, samt i den turordning de bör implementeras, för att få en bättre struktur på underhållsarbetet på Valmets gjuteri. De två enskilt viktigaste delarna i planen är enligt mig dels att anställa en person som ansvarar för den dagliga driften av underhållet. Samt att implementera underhållssystemet AM-underhåll, så att man kan få en bättre struktur på underhållsarbetet i form av arbetsordrar, mätetal och historik. / The report is about setting up an Implementation plan for a structured maintenance work on Valmet ABs foundry in Karlstad. This work is the final part for the Degree of Bachelor of Science in mechanical engineering and takes place at Karlstad University in the spring of 2014. Valmet has recently bought the foundry at Lamberget in Karlstad. The maintenance work is much neglected and in the current state there is no good structure. The maintenance work is in need of systemization and integration into Valmets other maintenance organization. The purpose of the project is to develop a plan Implementation plan for a structured maintenance work on Valmet ABs foundry in Karlstad. The project is divided into three phases. - Situational analysis through both interviews of maintenance personnel and identifying the current equipment - Create a vision of how they want to work with maintenance through benchmarking against other similar businesses, and literature studies - Establishment of a plan for how to get there. What activities to be performed and in what order The work is based on the methodology TPM (total productive maintenance). However it is not about an implementation of TPM, but limited to certain parts. From interviews with the maintenance staff at the foundry, observational studies and an identification study of the machinery, a situational analysis has been made. This situation analysis has shown the problems and challenges that exist in the maintenance department at the foundry. A vision of how they want to work with maintenance on the foundry has been drawn, based on study visits and interviews with management staff. It is most vital that emerged in this phase is the importance of management commitment to implement a process of change. A good communication both between the different departments and within the group is also vital. Using the two phases above, together with the theory processed during the project, a plan has been established for a more structured maintenance. The plan includes 12 stages that addresses the activities that should be implemented, and in what order, in order to get a better structure on maintenance work at the foundry at Valmet. The two single most important elements of the plan are, in my mind, to hire a person who is responsible for the daily operations of the maintenance work. As well as to implement the maintenance system AM-underhåll, so you can get a better structure to the maintenance work in the form of work orders, metrics and history.
9

Desempenho de poliuretanos termoplásticos particulados como adesivo para indústria calçadista

Bockorny, Geovana de Avila January 2016 (has links)
Elastômeros termoplásticos têm sido largamente empregados como adesivos hot melt em diferentes setores da indústria. Neste trabalho foram estudados dois copolímeros em bloco de poliuretano na forma particulada, base poliéster (TPU1) e policaprolactona (TPU2), com o objetivo de avaliar o desempenho dos mesmos como adesivos particulados. Foram preparadas diferentes composições dos TPUs com aditivos de policarbodiimida (A), resina hidrocarbônica (B) e poliisocianato (C). Os TPUs aditivados em diferentes composições foram avaliados por termogravimetria (TGA) e calorimetria diferencial de varredura (DSC) e quanto à resistência da colagem. A cinética de cristalização dos TPUs particulados puros e aditivados em diferentes isotermas foi acompanhada por DSC. Os adesivos TPU1 apresentaram velocidade de cristalização mais lenta, com exceção do TPU1 contendo os aditivos A e B (TPU1AB). Os adesivos TPU2 apresentaram taxa de cristalização maior somente quando aditivado com mistura de aditivos (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). O expoente de Avrami (n) foi inferior para os TPUs aditivados, o que sugere a ocorrência de alteração no tipo de nucleação e geometria de crescimento dos cristalitos. Os TPU1 (poliéster) e TPU2 (policaprolactona) apresentaram perfil de degradação térmica diferenciados devido a diferenças na estrutura química dos mesmos. Os adesivos TPU2 apresentaram valores de resistência mecânica mais elevados que os TPU1, em colagens de substratos de PVC. Os adesivos com maiores valores de resistência (TPU1A e TPU2A) foram extrusados e micronizados para uso como tal. O adesivo TPU1A micronizado apresentou aumento da resistência mecânica. As colagens com os adesivos TPU1 e TPU2 apresentaram falha coesiva e as composições TPU1B e TPU2AC demonstraram falha coesiva e adesiva em ensaio de tração. O processamento dos adesivos TPU1 por tratamento de plasma favoreceu um incremento dos valores de resistência de colagens em substratos de PVC. / Thermoplastic elastomers have widely been used as hot melt adhesives in different industry sectors. In this paper were studied two polyurethane block copolymers in particulate form, based polyester (TPU1) and polycaprolactone (TPU2), in order to evaluate their performance as adhesives. Different compositions of TPUs were prepared with polycarbodiimide (A), hydrocarbon resin (B) and polyisocyanate (C) additives. The TPUs with additives in different compositions were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) and by the bond strength. The kinetics crystallization of pure and additivated TPUs at different isotherms were followed by DSC. The TPU1 adhesives showed lower crystallization rate, except the TPU1 with both A and B additives (TPU1AB). The TPU2 adhesives showed higher crystallization rate only when formulated with mixture of additives (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). The Avrami exponent (n) was lower for the TPUs containing additives, which suggests changes in the nucleation type and crystallites growth geometry. The thermal degradation profile of both TPU1 (polyester) and TPU2 (polycaprolactone) adhesives were quite different due to chemical differences. The TPU2 adhesives showed higher strength values than TPU1s on PVC substrates. The adhesives with higher bond strength (TPU1A and TPU2A) were extruded and micronized, and the TPU1A adhesive showed improved bonding property. The TPU1 and TPU2 adhesives on PVC collages showed cohesive failure and the TPU1B and TPU2AC compositions showed cohesive and adhesive failure under tension test. The adhesive plasma treatment promoted a bonding increasing of TPU1 on PVC substrates.
10

Desempenho de poliuretanos termoplásticos particulados como adesivo para indústria calçadista

Bockorny, Geovana de Avila January 2016 (has links)
Elastômeros termoplásticos têm sido largamente empregados como adesivos hot melt em diferentes setores da indústria. Neste trabalho foram estudados dois copolímeros em bloco de poliuretano na forma particulada, base poliéster (TPU1) e policaprolactona (TPU2), com o objetivo de avaliar o desempenho dos mesmos como adesivos particulados. Foram preparadas diferentes composições dos TPUs com aditivos de policarbodiimida (A), resina hidrocarbônica (B) e poliisocianato (C). Os TPUs aditivados em diferentes composições foram avaliados por termogravimetria (TGA) e calorimetria diferencial de varredura (DSC) e quanto à resistência da colagem. A cinética de cristalização dos TPUs particulados puros e aditivados em diferentes isotermas foi acompanhada por DSC. Os adesivos TPU1 apresentaram velocidade de cristalização mais lenta, com exceção do TPU1 contendo os aditivos A e B (TPU1AB). Os adesivos TPU2 apresentaram taxa de cristalização maior somente quando aditivado com mistura de aditivos (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). O expoente de Avrami (n) foi inferior para os TPUs aditivados, o que sugere a ocorrência de alteração no tipo de nucleação e geometria de crescimento dos cristalitos. Os TPU1 (poliéster) e TPU2 (policaprolactona) apresentaram perfil de degradação térmica diferenciados devido a diferenças na estrutura química dos mesmos. Os adesivos TPU2 apresentaram valores de resistência mecânica mais elevados que os TPU1, em colagens de substratos de PVC. Os adesivos com maiores valores de resistência (TPU1A e TPU2A) foram extrusados e micronizados para uso como tal. O adesivo TPU1A micronizado apresentou aumento da resistência mecânica. As colagens com os adesivos TPU1 e TPU2 apresentaram falha coesiva e as composições TPU1B e TPU2AC demonstraram falha coesiva e adesiva em ensaio de tração. O processamento dos adesivos TPU1 por tratamento de plasma favoreceu um incremento dos valores de resistência de colagens em substratos de PVC. / Thermoplastic elastomers have widely been used as hot melt adhesives in different industry sectors. In this paper were studied two polyurethane block copolymers in particulate form, based polyester (TPU1) and polycaprolactone (TPU2), in order to evaluate their performance as adhesives. Different compositions of TPUs were prepared with polycarbodiimide (A), hydrocarbon resin (B) and polyisocyanate (C) additives. The TPUs with additives in different compositions were evaluated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) and by the bond strength. The kinetics crystallization of pure and additivated TPUs at different isotherms were followed by DSC. The TPU1 adhesives showed lower crystallization rate, except the TPU1 with both A and B additives (TPU1AB). The TPU2 adhesives showed higher crystallization rate only when formulated with mixture of additives (TPU2AB; TPU2BC; TPU2ABC; TPU2AC). The Avrami exponent (n) was lower for the TPUs containing additives, which suggests changes in the nucleation type and crystallites growth geometry. The thermal degradation profile of both TPU1 (polyester) and TPU2 (polycaprolactone) adhesives were quite different due to chemical differences. The TPU2 adhesives showed higher strength values than TPU1s on PVC substrates. The adhesives with higher bond strength (TPU1A and TPU2A) were extruded and micronized, and the TPU1A adhesive showed improved bonding property. The TPU1 and TPU2 adhesives on PVC collages showed cohesive failure and the TPU1B and TPU2AC compositions showed cohesive and adhesive failure under tension test. The adhesive plasma treatment promoted a bonding increasing of TPU1 on PVC substrates.

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