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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.
81

Modernisering av driv- och vändstation för timmersortering

Kihlgren, Erik, Masterdalshei, Jonas January 2010 (has links)
<p>The purpose of the rebuild of Notnäs AB timber sorting line is to renew the existing drive and turning ends of the transport chain, which has become old. This means that Notnäs AB have problems to get new parts if the gearbox and chain are worn out. They also require that the rebuild should have a maintenance schedule for the new spare parts that will be used in the rebuild. Maintenance workers placed great emphasis on that in a rebuild it shall be a service-friendly design. The maintenance schedule used in Notnäs AB in the current situation is from Statoil and the report uses SKF formulas and recommendations in order to obtain a lubricating schedule. The rebuild has been made in Pro Engineers skeletal structure with a top-down structure. Notnäs AB will have all the CAD files as well as complete drawings that make it possible for the rebuild to take place after the summer of 2010. After a summary of the CAD it revealed that a rebuild of timber sorting line was possible. Parts of the draw-ings are available in a reduced format of the report. Drawings have been approved and work on the rebuild can be started by Notnäs AB.The purpose of the rebuild of Notnäs AB timber sorting line is to renew the existing drive and turning ends of the transport chain, which has become old. This means that Notnäs AB have problems to get new parts if the gearbox and chain are worn out. They also require that the rebuild should have a maintenance schedule for the new spare parts that will be used in the rebuild. Maintenance workers placed great emphasis on that in a rebuild it shall be a service-friendly design. The maintenance schedule used in Notnäs AB in the current situation is from Statoil and the report uses SKF formulas and recommendations in order to obtain a lubricating schedule. The rebuild has been made in Pro Engineers skeletal structure with a top-down structure. Notnäs AB will have all the CAD files as well as complete drawings that make it possible for the rebuild to take place after the summer of 2010. After a summary of the CAD it revealed that a rebuild of timber sorting line was possible. Parts of the draw-ings are available in a reduced format of the report. Drawings have been approved and work on the rebuild can be started by Notnäs AB.</p>
82

Konceptutveckling för lampdesign : The developing concept of lamps

Jansson, Jenny, Madsen, Maria January 2008 (has links)
<p><strong><strong><p>Abstract</p><p>This thesis was conducted by Jenny Jansson and Maria Madsen, students at the Faculty of</p><p>Technology and Science and the Innovation and Design Engineer programme at Karlstad</p><p>University, during the spring 2008. The thesis covers 22,5hp for each student. Anna</p><p>Holmquist and Chandra Ahlsell at the company FOLKFORM were the ones who requested</p><p>the theis, their company are located at Stora Skuggan in Stockholm. Tutor for this thesis was</p><p>Lennar Wihk and the examiner was Monika Jakobsson of Karlstad University.</p><p>The given assignment came from FOLKFORM and the aim for the thesis was to create a</p><p>further development of two already existing lamps from an earlier collection at FOLKFORM,</p><p>“Jaipur” and “Modern Times”. The students used their creativity and ability to come up with</p><p>fresh ideas and new innovations with the lamps current design, but also considering</p><p>material, manufacturing methods and the environment.</p><p>Throughout the working process it was evident to create an exclusive concept yet a cheap</p><p>concept for each lamp, where the main criteria were to make the material enlighten the</p><p>feeling.</p><p>Apart from these concepts new ones for the packing was to be evolved, one concept for</p><p>each one of the lamps.</p><p>Through extensive research of materials, production methods and the market and consumer</p><p>needs, which generated in many ideas. The final stage was with the product of a concept</p><p>development. The chosen concept then generated in this thesis, with concept developing</p><p>and prototype developing, and four actual products, well conducted concepts of the lamps</p><p>Palmett and Rotation in the final stage.</p><p>The result of the thesis was, as mentioned above, four prototypes in 1:1 scale, an exhibition,</p><p>a PowerPoint presentation and a written thesis report.</p><p>Expectations are that FOLKFORM are willing to use the concept made by the two students in</p><p>their own making when it comes to the developing of earlier collections, were the lamps are</p><p>represented.</p></strong></strong></p>
83

Smaksatt vatten : Implementering av smaksättning av vatten i kaffemaskiner

Olsson, Pär January 2008 (has links)
This degree project is a part of the mechanical engineer program at the University of Karlstad. The project has been fulfilled during 15 weeks in collaboration with Coffee Queen AB. Coffee Queen is a company that produces professional coffee machines. The company is a leading supplier of coffee machines to offices, restaurants and fast food industries. The assignment has been to develop an operating concept of a system that will flavour carbonated water. This due to the fact that one of Coffee Queens greatest customer submitted wishes to get this function on their coffee machines. The solution that came up was that with help of a pump dose the right amount of floating essence. Then this essence mixes with the carbonated water in a mixing faucet and then dispenses out into a glass. The project resulted in a simple working prototype. The finished product will probably get in bulk production in the beginning of 2009 / Detta examensarbete är en del i maskiningenjörsutbildningen vid Karlstads universitet. Arbetet har genomförts under 15 veckor tillsammans med uppdragsgivaren Coffee Queen AB i Arvika. Coffee Queen är ett företag som tillverkar kaffemaskiner för professionellt bruk. Företaget är ledande leverantör av kaffemaskiner till kontor, restauranger och snabbmatskedjor. Uppgiften har varit att ta fram ett fungerande koncept för hur smaksättning av kolsyrat vatten kan ske. Detta efter att en av Coffee Queens största kunder har efterfrågat denna funktion i sina kaffemaskiner. Lösningen blev att med hjälp av en pump, dosera ut rätt mängd flytande essens. Denna essens blandas sedan med det kolsyrade vattnet i en blandningsventil, för att sedan dispenseras i ett glas. Projektet har resulterat i en enkel prototyp. Den färdiga produkten kommer troligtvis att börja serietillverkas i början av 2009.
84

Postväskan / The mailbag

Johansson, Emmelie, Skarius, Johan January 2009 (has links)
This Degree project for Degree of Bachelor of Science in Innovation and Design Engineering has been carried out by Emmelie Johansson and Johan Skarius at the Faculty of Technology and Science at Karlstad’s university during spring 2009. The Degree project extends 22,5ECTS credits.   The commissioning body for this project has been Posten messaging AB, production and processes. The orderer and supervisor was Arne Grentzelius. Supervisors and examiners at Karlstad’s university were Monica Jakobsson and Lennart Wihk. Posten is one of the Nordic regions largest messaging and logistics operators. They are serving 4.5 million homes and 900 000 businesses daily.   Posten messaging AB is a daughter company to Posten AB. Posten messaging includes both post activities for private customers and companies. The service contains mail distribution and news distribution. Mail distribution gives Posten the largest incomes. Posten distributes both unaddressed and addressed direct mail. Their main country is Sweden. There are about 15000 mailmen in Sweden and 2750 of them are delivering mail by bicycle.   Posten has a problem with the front mailbag on the bicycle and want it to be improved. That is how the students got their assignment. The assignment is to find a better solution of the mailbag. Today’s mailbag has some problems, like its short lifetime, high price and its rain cover allows almost no resistance against rain.   To fulfil all the mailmen’s needs, an extensive analysis of the current market as interviews, inquiries and study visits were made. A several manufacturing companies were contacted by the students, about technical possibilities and estimates of price of the future product. These were followed by generating innovative ideas and identify those which are most likely to become successful concepts.   The final product is made of a plastic material or a composite material (such as glass fibre) which gives it a much longer lifetime together with, more stability and a very advantageous price. Most accessories have been integrated to the manufactoring, which makes it easier to deliver mail. The rain cover has been more resistant of the penetration of rain and designed to fit the mailbag.   The degree project resulted in a prototype in a 1:1 scale, 3D-visualisations, an academic report, a final presentation and an exhibition
85

Konstruktion av bottenlocket till kalottventil PN25 DN500

Sjöman, Ola, Bergkvist, Gustav January 2008 (has links)
Av vår uppdragsgivare SOMAS i Säffle har vi fått uppgiften att konstruera ett bottenlock till kalottventil DN500 PN25. Vårt mål med arbetet är att minimera vikt och bearbetnings kostnad för locket. Materialet består av CF8M enligt Amerikansk standard.[2] Locket ska godkännas enligt SS-EN 13445-3:2002.[1] För FEM-analys används bilaga C design by analysis. [1] Locket ska analyseras i 3 lastfall. <ul type="disc">  <ul type="circle">Täthetsprovning av sätet, påverkar locket med en radiallast Tryckprovning, påverkar locket med en övertryckslast Drift baklänges, både radiallast och inre övertryck   Med utgångspunkt från kalottventil DN500 PN10, som har identisk axel och kalott, analyserades locket till DN500 PN10 i Abaqus med övertrycket 25bar. Där locket inte uppfyllde kraven sattes stödfjädrar för att styva upp locket. Vid låga spänningar togs det bort material för att reducera vikten.   Lastfall 1 och 2 godkändes statiskt och temperaturberoende. Lastfall 3 underkändes då de linjäriserade spänningarna inte klarade kraven för ventilen. Locket kan inte styvas upp mer då styvfjädern skulle gå in i skruvförbandet. Då inte lastfall 3 får godkänt enligt standard [1] ändrades det värsta fallet för ventilen till lastfall 1 som beräknades med de två olika materialstandarderna SS-EN10213-4 Nr 1,4408 [3] och ASTM A351 CF8M [2] och det blir godkänt i båda fallen även om det är ett gränsfall med den europeiska standarden. Ventilen kan köras i lastfall 3 med reducerat tryck, motsvarande 10 Bar med europeisk standard och 11 bar med amerikansk materialstandard. Lastfall 1 klarar inte kraven för utmattning.      Det vi kommit fram till för att ett nytt examensarbete ska kunna genomföras är att centrera locket under huset vilket skulle skapa plats för stödfjädrar på lockets framsida. Att minska kontakttrycket borde även det vara önskvärt, vilket skulle åstadkommas med en ökad axeldiameter. / By our employer SOMAS in Säffle we have been given the assignment to design a bottom lid for the ball segment valve PN25 DN500. Our goal is to minimize the weight and the manufacturing cost of the lid. The material consists of CF8M according to American standard.[2] The lid will be approved according to appendix C FEM-analys. [1]   The lid will be analyzed in 3 load cases. <ul type="disc">Seat tightness test, affects the lid with a radial force Pressure testing, open valve Operation backwards to the valve, both radial force and inner pressure   With base from DN500 PN10, which have identical shaft and ball segment, the lid PN10 DN500 was analyzed in Abaqus with the pressure 25 Bar. Where the lid didn’t reached up to the demands, ribs where placed to stiffen up the lid. If there where low tension material where removed to lower weight.   Load case 1 and 2 where approved for static and temperature dependence. Load case 3 failed when the stress linearization didn’t meet up to the demands for the valve. Due to the lack of space to build out more material the lid could not be stiff enough to support the load. Load case 3 was cleared at 10 bar by European standard [3] and 11 bar by American standard. [2] Load case 1 is not approved for fatigue. We have come to the conclusion that a new graduation work can be done if the housing could be centered under the house to make room for a longer rib to support the housing. To decrease the contact pressure an increase in shaft diameter would be wanted.
86

Produktutveckling av dryckespump

Andersson, Lars-Åke January 2009 (has links)
This work is a product development of a product which facilitates enduro drivers swallowing fluid while driving. My own experience of the problem and a custom survey gave me some frames and requirements of how such a product would look. To obtain the different concepts the method of brainstorming was used where I outlined the various proposals. The basic concept was that some kind of pump would build pressure in the liquid and when the user opens the nozzle the liquid will come out without the need to use the mouth to suck. The screening phase consisted of two steps. The first step, a Pugh matrix where I varied reference concepts and four of the six proposals were eliminated. During the second screening phase, two test models were built and I tried out which one I would eliminate. The concept that was left was a simple pump, powered by a battery of9-volt. The pump starts when the user opens the nozzle and stops automatically when the nozzle is closed.  This is controlled by a hose which swells when the pump is running and the nozzle is closed. Then the hose begins to swell and affects a small micro switch that breaks the voltage supply to the pump. A check valve makes sure that the liquid remains in the hose and the pump will remain neutral until the re-opening of the nozzle and the hose shrinks.
87

Effektivisering av arbetsplats : Effektivisering av monteringsplats vid Wigells AB / Increase the assembly efficiency : Streamlining of the assembly area at Wigells AB

Jarlö, Marcus, Holmgren, Jonas January 2009 (has links)
The work presented in this report is written at IEIs department on Linköping Institute of Technology. The report aims to increase the assembly efficiency at Wigells AB. The report shall be used as a guide for the implementation of changes at other workstations in the company. Together with Träcentrum in Nässjö, Wigells AB has identified the needs of this study and contacted IEI at Linköping Institute of Technology. In order to implement an efficient assembly line at the company, studies on lean production have been made. This theory has been studied and together with our own views and findings at the company we have analyzed the assembly area. Wigells is a small company that manufactures wood furniture. A major problem for the assembly of the pin seats is that the company has a wide range of different models and designs. In order to identify problems and possible improvements we first carried out a current state analysis of the assembling area. The current state analysis shows that there are many operations in the manufacture of pin seats which are routine. Production consists today of manual operations and no automatic equipment. The company does not wish to acquire any automatic equipment. The assembly location is perceived by outsiders and employees of the company as disorganized. After the current state analysis was conducted and compiled, problems were identified in order to enable improvements. Identified difficulties in assembly: Difficult to get an overview of the assembly area, it is perceived disorganized and cluttered assembly area No documentation for assembly Defective components from external suppliers Defective components from internal machines In order to create solutions to problems discovered we had to link theory and our own views together to suggest new proposals. The major problem requiring a solution is how to pass on the existing craftsmanship and knowledge.To enhance the efficiency of the assembly area many small changes that are suggested must be implemented. The company should get the staff involved in the changes proposed in this work to get best result.
88

Konstruktion av pipelinebro i Charagua, Bolivia

Gunstedt, Andreas, Bergström, Samuel January 2009 (has links)
Guazuigua is a small village in Bolivia, which has had too small water resources, especially for irrigation. A project started after some studies were made, to create a canal to provide the village with water from a nearby town. To make the canal work it had to cross a dried out river. There have been several attempts to cross these dried out rivers, but with poor results. The purpose of the report is to provide a solution for this problem. During the field studies, the project changed direction, and a decision was made to build a well system instead. This proved to be a better solution for the village’s water problem. The report still remained with solving the canal problem. Calculations show that a pipe placed across the dried out river would break down. The report suggests a support construction which resembles a cable stayed bridge, which is build economical and by materials accessible in the area. / Guazuigua är en liten by i Bolivia som länge haft för liten tillgång på vatten, och främst i bevattningssyfte. Efter att en förstudie gjorts startades ett projekt att med ett kanalsystem förse byn med vatten från närliggande stad. Projektet finansieras av en personlig gåva. För att kanalsystemet skulle kunna genomföras behövdes en akvedukt byggas där kanalen är tvungen att passera en uttorkad flodbädd. Metoder att leda vatten över dessa flodbäddar har gjorts på ett flertal platser i området, där konstruktionerna havererat. Rapportens syfte är att bidra med en lösning på detta problem. Mitt under fältstudien förändrades projektets inriktning, varav man valde att bygga ett brunnsystem istället. Denna förändring var en bättre lösning på byns vattenproblem. Rapporten kvarstod ändå vid att lösa problemet med akveduktkonstruktionen. Beräkningar visar att ett fritt liggande rör över flodbädden skulle plasticera och haverera. Rapporten föreslår en stödkonstruktion som liknar en kabelupphängd bro, som är byggd på material som är billiga, och finns tillgängliga i området.
89

Automatisering av flexibel fixtur

Avdic, Nermin January 2009 (has links)
This thesis was conducted at Linköping University and SAAB Aerostructures, Linköping, and focuses on the automation of flexible fixturing in machining applications. At Linköping University a project called "Koofix" is conducted with support from Strategiska stiftelsen and several manufacturing industries including SAAB Aerostructures. The purpose of this project is to develop a more cost-effective, flexible, technique for fixation of workpieces during processing and assembly. Fixtures are an important part during the machining process, especially if you process the parts with high accuracy. Today a large number of fixtures are used at SAAB and they would prefer to reduce the number of fixtures by using flexible fixtures instead. SAAB uses one fixture for each article and this result in a high fixture cost and it also takes time to design and construct a new fixture. There are several advantages with using a flexible fixture such as that you can process workpieces with different length, height and thickness in the same fixture. Bigger workpieces takes time to fasten in the fixture because the machine operator must tighten the clamps by hand. By automating the fixture with for example grippers or clamping cylinders the set time would be reduced because the clamping process is automatic. In this report there is also a mapping of various flexible fixture components such as grippers, clamping cylinders and linear units. These components are quite common today in the processing industry and are also used in fixtures. The idea of flexible components is to provide a more flexible and automated fixture then the currently used at SAAB. These components were also linked to a concept idea and based on this idea, several concepts were sketched. The result of the concept idea was two concepts that were generated in the CAD program CATIA. The first concept uses grippers for the clamping process and for additional flexibility the grippers can also be rotated with rotary actuators. Linear units are used to automatically position the beams to reduce the set time. The second concept uses clamping cylinders and rotary grippers to clamp the workpiece. Beams are positioned by an operator, but linear units could also be used in this concept as well. Finally, the concepts were evaluated according to a method from Ullman with a so called decision matrix. The concept that fulfilled the criteria best was concept 1, which uses grippers and linear units. Another method that was used from Ullman was a QFD (Quality Function Deployment) chart and this chart shows the design requirements that are important and that should be fulfilled. The components that are presented in this report have not been tested. This could be a suggestion in an upcoming work to test these components. For example the pneumatic linear units with passive or active brake could be tested to make sure that the braking force is sufficient.
90

To increase the efficiency in sugar and ethanol industries by using a decanter centrifuge : a feasibility study made in the Dominican Republic

Sjöberg, Mikael, Nilsson, Daniel, Widén, Pontus January 2008 (has links)
This Bachelor Degree Project is a study about possible improvements of the efficiency at sugar mills and ethanol distilleries by using a decanter centrifuge. The report handles background, purpose and result including conclusions and discussions. The implementation of the decanter at site is fully described, including problems and solutions during the project. With the increased use of ethanol as a bio fuel, the question about bio ethanol’s energy balance have become of more importance. As a part of the project a study about the energy balance have been carried out. In our research we did only find one (more or less) accepted investigation concerning ethanol energy balance from sugar cane. All other found information about the subject refers to this single assessment which is quite remarkable. The sugar and ethanol production processes are almost similar until after the clarifier step. The clarifier is a gravitational settling tank where the juice is clarified and then sent to evaporation (sugar process) or fermentation (ethanol process). The by-product called molasses still contains some sugar and is therefore sent to a rotating vacuum filter to extract the remaining sugar. Rotating vacuum filters has high energy consumption, is dirty, creates a lot of smell and needs a lot of space. The objective with the study was to investigate the possibilities to replace the rotating vacuum filter with a decanter centrifuge and achieve better efficiency in the production. A decanter is a centrifuge that separates solids from liquids. The decanter is based on the simple theory that solids fall to the bottom due to the force of gravity. The decanter centrifuge works with this principle but the difference is that the gravity force has been replaced by a centrifugal force. The result of our test gives a good indication that the decanter is a good investment. The payback time is short and the investment gives many positive side effects such as less energy consumption, better working environment and it needs less space in the factory. / El proyecto para el título de bachiller se basa en un estudio de las posibles mejoras a la eficiencia en los ingenios azucareros y destilerías de etanol mediante la aplicación de un decantador de centrifugación. El informe explica los antecedentes, las partes implicadas y de la finalidad del proyecto. El procesamiento del azúcar es descripto en breve, ya que el proceso es similar al del etanol hasta después del proceso clarificador. El clarificador es un tanque de solución gravitacional donde el jugo se aclara y luego enviado para a la evaporación (proceso del azúcar) o para la fermentación (proceso del etanol). El sub-producto obtenido, denominado melaza de azúcar todavía incluye algunos azúcares y es por lo tanto enviado a un filtro rotatorio de vacío para extraer el azúcar restante. El filtro rotatorio de vacío es una antigua técnica utilizada en el proceso del azúcar. Tiene un alto consumo de energía, es muy voluminoso, emana gran cantidad de olores, y necesita asimismo de mucho especio. El Proyecto investiga la posibilidad de reemplazar el filtro de rotación al vacío por un decantador centrífugo y adquirir mayor eficiencia. El decantador es un centrifugador que separa sólidos de los líquidos. Está basado en la teoría de que los sólidos caen al fondo por la fuerza de gravedad. Se basa en la sencilla teoría de que los sólidos caen a la parte inferior debido a la fuerza de la gravedad. El decantador de centrífugo trabaja con este principio, pero la diferencia es que la fuerza de gravedad ha sido sustituida por una fuerza centrífuga. La aplicación en el sitio se describe de forma detallada, incluyendo todos los problemas y soluciones durante el proyecto. Con el aumento del uso de etanol como bio-combustible, la cuestión acerca del balance de energía de bio etanol ha tomado mayor importancia. En nuestra búsqueda, encontramos únicamente una investigación precisa concerniente al etanol de la caña de azúcar. Los resultados se presentaron y discutieron antes de dar la conclusión del proyecto.

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