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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

Torkning av plastgranulat : En jämförande undersökning av energibesparingsalternativ / Drying of Plastic Granules : A Comparative Investigation of Energy saving Alternatives

Persson, Hans, Hyltse, Emanuel January 2010 (has links)
<p>With increasing energy prices and more demanding competition within the manufacturing industry Swedish corporations are forced to decrease their energy needs to handle being profitable on the market.</p><p>We have with this report tried to help Nexans IKO Sweden AB in Grimsås to decrease the energy use in drying plastic granules in their cable production. We also did an inventory of their machine park for drying plastic granules at the time being.</p><p>An investigation of the market was also done to analyze what other possibilities there are for drying and what the future looks like. Our own tests were done with plastic granules to get an understanding for how the material behaves when drying it and re-moisturising it.</p><p>What we quickly discovered is that the handling of the desiccant dryers is very important to get it as economic as possible in use. It was also discovered that batch drying should be avoided as far as possible because it is uneconomical in many aspects; the material is re-moisturising among others. Another advantage with avoiding batch drying is that hot material reaches the extruder that in turn will not have to heat the material as much.</p>
2

Torkning av plastgranulat : En jämförande undersökning av energibesparingsalternativ / Drying of Plastic Granules : A Comparative Investigation of Energy saving Alternatives

Persson, Hans, Hyltse, Emanuel January 2010 (has links)
With increasing energy prices and more demanding competition within the manufacturing industry Swedish corporations are forced to decrease their energy needs to handle being profitable on the market. We have with this report tried to help Nexans IKO Sweden AB in Grimsås to decrease the energy use in drying plastic granules in their cable production. We also did an inventory of their machine park for drying plastic granules at the time being. An investigation of the market was also done to analyze what other possibilities there are for drying and what the future looks like. Our own tests were done with plastic granules to get an understanding for how the material behaves when drying it and re-moisturising it. What we quickly discovered is that the handling of the desiccant dryers is very important to get it as economic as possible in use. It was also discovered that batch drying should be avoided as far as possible because it is uneconomical in many aspects; the material is re-moisturising among others. Another advantage with avoiding batch drying is that hot material reaches the extruder that in turn will not have to heat the material as much.
3

Temperaturstyrning av aluminiumextruderingsprocess / Temperature control of aluminium extrusion process

Nilsson, Richard January 2003 (has links)
<p>In this final thesis a rough description of aluminium extrusion is made, the importance of temperature of both the raw material and the extruded profile for a good profile quality. The difficulty in controlling these temperatures are discussed and attempts to increase the control are described. The attempts are basically made by controlling the furnace that is heating the raw material. This is done in a manner that the raw material reaches its final temperature shortly before it is extruded. An IR-camera at the press can be used for profile temperature measurements. The profile temperature is in turn used to decide the raw material temperature. Finally some proposals are given that can lead to a more controlled temperature at raw material and profile.</p>
4

Ergo Mopp : Från koncept till produkt / Ergo Mop : From concept to product

Kamf, Tobias January 2010 (has links)
<p>This thesis describes the work process and the results for the development of a newkind of ergonomic cleaning mop, ranging from basic concept to a virtually productionready digital prototype. The project was made in cooperation with, Ömer Altun, whowas also the project supervisor, and whose plan it is to launch this new product onthe market in a foreseeable future. The mop is meant to be used by both professionalcleaning staff and ordinary home users. What makes this product unique is that it hasa movable center piece that simplifies the cleaning under low furniture.The work began with the establishment of a product requirements specification andlater a study of similar products and existing functional models was conducted. Afterthese surveys the work began with refining the existing concepts in order to makethem more complete. In consultation with Ömer, further refining of one of these newconcepts was conducted, but was split into seven smaller steps.After the initial refining process, effort shifted into the investigation and selection ofappropriate materials and manufacturing methods. At this stage, two experimentswere also conducted and subsequently used to support the final decisions concerningthe choice of materials and design.When the materials and methods were adopted, a detailed CAD model of the wholeproduct and related technical drawings was made and also a number of FEM-analyseson all critical details, to ensure that performance requirements were met, wasconducted. These CAD models are closer described in detail in the chapter“Detaljkonstruktion”.In the final sections of discussion and evaluation are suggestions for furtherimprovements. And also some evaluation of the work process and the problems andsolutions encountered during the project execution.</p>
5

Ergo Mopp : Från koncept till produkt / Ergo Mop : From concept to product

Kamf, Tobias January 2010 (has links)
This thesis describes the work process and the results for the development of a newkind of ergonomic cleaning mop, ranging from basic concept to a virtually productionready digital prototype. The project was made in cooperation with, Ömer Altun, whowas also the project supervisor, and whose plan it is to launch this new product onthe market in a foreseeable future. The mop is meant to be used by both professionalcleaning staff and ordinary home users. What makes this product unique is that it hasa movable center piece that simplifies the cleaning under low furniture.The work began with the establishment of a product requirements specification andlater a study of similar products and existing functional models was conducted. Afterthese surveys the work began with refining the existing concepts in order to makethem more complete. In consultation with Ömer, further refining of one of these newconcepts was conducted, but was split into seven smaller steps.After the initial refining process, effort shifted into the investigation and selection ofappropriate materials and manufacturing methods. At this stage, two experimentswere also conducted and subsequently used to support the final decisions concerningthe choice of materials and design.When the materials and methods were adopted, a detailed CAD model of the wholeproduct and related technical drawings was made and also a number of FEM-analyseson all critical details, to ensure that performance requirements were met, wasconducted. These CAD models are closer described in detail in the chapter“Detaljkonstruktion”.In the final sections of discussion and evaluation are suggestions for furtherimprovements. And also some evaluation of the work process and the problems andsolutions encountered during the project execution.
6

Temperaturstyrning av aluminiumextruderingsprocess / Temperature control of aluminium extrusion process

Nilsson, Richard January 2003 (has links)
In this final thesis a rough description of aluminium extrusion is made, the importance of temperature of both the raw material and the extruded profile for a good profile quality. The difficulty in controlling these temperatures are discussed and attempts to increase the control are described. The attempts are basically made by controlling the furnace that is heating the raw material. This is done in a manner that the raw material reaches its final temperature shortly before it is extruded. An IR-camera at the press can be used for profile temperature measurements. The profile temperature is in turn used to decide the raw material temperature. Finally some proposals are given that can lead to a more controlled temperature at raw material and profile.
7

Jämförande av kvalitet på extruderade profiler under nya produktionsförhållanden, på Profilgruppen / Comparison of quality of extruded products under new production conditions, at Profilgruppen

Jonasson, Gunnar, Ingvarsson, Alexander January 2020 (has links)
Dagens extruderande industrier blir allt mer efterfrågade på grund av sin förmåga att producera komplicerade geometrier med hög hållfasthet. Men för att bibehålla sin placering i den konkurrentkraftiga marknaden måste utveckling göras. Därför är målet med denna rapporten att undersöka en utvald profil som har producerats i olika produktionsförhållanden, för att se hur kvaliteten förhåller sig mellan de olika produktionsförhållandena. Detta har genomförts genom drag- och hårdhetsprover som har utförts på de olika profilerna, resultatet av detta gav en uppfattning att det faktiskt finns mätbar skillnad. För att konkret säga vad som ska göras för att neutralisera skillnaden, finns det alldeles för många faktorer och parametrar inblandade. Därför hade ett experiment där en produkt produceras med en parameterändring i taget för att se vad det är som påverkar resultatet rekommenderas.
8

Evaluation of Woodmer/plastic composites / Evaluering av Woodmer/plast kompositmaterial

Ahlström, Leon January 2023 (has links)
Plast ger otroliga möjligheter i form av stor variation för materialanvändning. Tyvärr sker det dock på bekostnad av miljön då de ackumuleras i naturen. En kompromiss mellan hållbarhet och fortsatt plastanvändning skulle kunna vara att använda biomassa som fyllnadsmaterial i plastkompositer istället för plast. Detta skulle i sin tur minska mängden plast och öka användningen av förnybara råvaror. Naturligtvis måste de mekaniska och termiska egenskaperna också vara av acceptabel kvalitet för materialtillämpningar och helst även erbjuda någon form av uppgradering av det redan existerande materialet. Ett potentiellt fyllnadsmaterial är Woodmer, en LCC (lignin kolhydrat komplex) som produceras av Ecohelix. Woodmers förmåga att agera som ett termoplastiskt kompositmaterial analyserades och jämfördes med de respektive jungfruliga termoplasterna. Tre olika plaster används som bas för kompositerna och dessa plaster var akrylnitril-butadien-styren (ABS), polymjölksyra (PLA) och lågdensitetspolyeten (LDPE). Resultaten visar att det är möjligt att skapa homogena Woodmer/termoplast kompositmaterial. När det gäller de termiska egenskaperna, så gav inte UL 94 någon brandklassificering på materialen, några positiva effekter observerades i TGA och resultaten från DSC var mestadels oförändrade jämfört med respektive jungfrulig plast. Dragprovning visade å andra sidan att de mekaniska egenskaperna påverkas negativt av högre Woodmer tillsatser men effekten varierade kraftigt mellan de olika plasterna då LDPE var minst påverkad och PLA mest påverkad. Framtida forskning bör fokusera på att tillverka material genom dubbelskruv extrudering eftersom det tyvärr fanns problem med blandningen i enkelskruv extrudering. Ytterligare forskning kring materialens morfologi, löslighet och så vidare krävs också för att se om kompositerna är lämpliga material eller om det finns några oförutsedda problem. / Plastics provide incredible opportunities in the form of great versatility for material usage. However, this comes at the cost of environmental issues as they accumulate in the environment. Therefore a compromise between sustainability and continued plastic usage is to use biomass as a filler material in plastic composites instead of virgin plastics. This would in turn reduce the amount of plastic and increase the usage of renewable raw materials. Of course the mechanical and thermal properties must also be of acceptable quality for material applications and preferably even offer some form of improvement to the preexisting material. One potential biomass filler material is Woodmer, a LCC (lignin carbohydrate complex) produced by Ecohelix. The viability of Woodmer as a thermoplastic composite material was analysed and compared to virgin thermoplastics. Three different plastics were used as basis for the composites and these plastics were Acrylonitrile-butadiene-styrene (ABS), polylactic acid (PLA) and low density polyethylene (LDPE). The results show that it is possible to create homogenous Woodmer/thermoplastic composites. As for the thermal properties, while the UL 94 provided no flame classification on the materials some positive effects were observed in TGA and the results from the DSC were similar to the virgin plastics. The tensile test on the other hand showed that the mechanical properties were negatively affected by increasing Woodmer additions but the effect varied substantially between the different plastics as LDPE was the least affected and PLA the most affected. Future research should focus on making the materials through twin screw extrusion as there were unfortunately issues with the mixing from single screw extruders. Further research regarding the materials morphology, solubility and so forth are also required to see if the composites are suitable materials or if there are any unforeseen issues.
9

Effektivisering av testmetod för produkter med låga plastytvikter : Streamlining the test method for products with low plastic surface weights

Azcárate,, Simon, Hellman Rönnqvist, Patricia January 2023 (has links)
Arbetet syftar till att hitta en effektivare metod för testning av produkter med låga plastytvikter. Problemet i dagsläget är att metoden är tidskrävande och kräver ett handhavande av personalen.De närmaste tre åren kommer företaget ha en volymökning på produkterna med låga plastytvikter vilket kommer leda till att mycket mer testning kommer behöva göras.Metoderna som använts har varit att samla in data i form av intervjuer, observationer av personalen och provtagning av nuvarande metod. När data hade samlats in behövde nuläget analyseras så att en testplan för ny datainsamling kunde göras i form av ett flertal tester. Resultaten från testerna visade att det går att lägga proverna i kläm så att de hålls utsträckta hela tiden. Det visades också att det går att skölja proverna i vattenbad, både vibrerande, cirkulerande och stilla, och att de kunde torkas i ugn och svamptork med bibehållen kvalitet. När proverna torkats kunde plast och papper enkelt separeras för att sedan kontrollvägas. En alternativ metod undersöktes, vilket är en metod där en tejpremsa tejpas på baspappersrullen vilket gör att plasten inte fäster till pappret vid extrudering. Denna metod gör så att proverna inte behöver ligga i lut, sköljas eller torkas eftersom plasten redan är separerad från pappret. Med denna metod kommer tiden i labbet att bli betydligt mycket mindre då det stora arbetet görs i produktionen av operatörerna. Resultaten som tagits fram är inte helt felfria utan det finns några aspekter att ha i åtanke, vilket är att det relativt få mätpunkter på de flesta av testerna. Detta gör att resultaten endast ger en indikation på att det fungerar. En annan aspekt att ha i åtanke är att när det vibrerandevattenbadet gjordes användes en massagepistol vilket inte är ett redskap som företaget kommer att använda om de väljer att applicera den ny metoden i sin verksamhet. Detta betyder att det kommer att krävas nya tester för det vibrationsverktyg som väljs eftersom det kan ha en annan vibrationsfrekvens jämfört med massagepistolen. Slutsatserna som kan härledas från examensarbetet indikerar att den nya metoden är betydligt mer tidsbesparande. Metoden har genomgått effektiviseringar och kan nu göras ännu mer effektiv, eftersom den är fullt skalbar i sin helhet. Den utvecklade metoden visar sig dessutom vara mer stabil, då handhavandet av proverna minskat och det då ställs lägre krav på laboratoriepersonalens fingerfärdighet. / The aim of this study is to identify a more efficient method for testing products with low plastic weights. The current challenge lies in the time-consuming nature of the existing method, requiring manual handling by personnel. Over the next three years, the company anticipates a significant increase in the volume of products with low plastic weights, necessitating a corresponding increase in testing activities.The methods employed, within this report, involved data collection through interviews, observations of personnel, and sampling of the current method. Once the data was gathered, an analysis of the current situation was undertaken to formulate a test plan for new data collection, involving several tests.The test results revealed that samples can be clamped to maintain their extended, flat position. It was also demonstrated that samples can be rinsed in a water bath—whether vibrating, circulating, or stationary—and subsequently dried in an oven or with a food dehydrator, while maintaining current quality. After drying, plastic and paper could be easily separated for subsequent weight measurements. An alternative method was explored, involving the application of a tape strip to the base paper roll, preventing plastic adhesion during extrusion. This method eliminates the need for samples to be immersed in a solution, rinsed, or dried since the plastic is already separated from the paper. Implementing this method in the laboratory significantly reduces the time spent, transferring the bulk of the work to the production operators.The results obtained are not without imperfections, as some tests had relatively few measurement points, providing indicative rather than conclusive results. Another consideration is the use of a massage gun during the vibrating water bath test—a tool not intended for use by the company if they choose to adopt the new method in their operations. Consequently, new tests will be required for the selected vibrating tool, as it may have a different vibration frequency compared to the massage gun.In conclusion, the project findings suggest that the new method is more time-efficient, indicating its optimization potential. Furthermore, the method is scalable, allowing for simultaneous testing of multiple samples. The developed method is also more stable, given the reduced manual handling of samples and the lower dexterity requirements for laboratory personnel
10

Expansionsmöjligheter hos Acheta domesticus : En studie om syrsmjölets påverkan på färg,textur, gillande och expansion i extruderadmajskrok. / Expandability of Acheta domesticus : A study on the effect of cricket flour on color, texture, liking and expansion in extruded corn puffs.

Andersson, Fredrik, Hansson, Mattias January 2020 (has links)
I takt med en ökande världspopulation ställs allt hårdare krav på primärproducenter att tillgodose råvaror i adekvata mängder. Forskning inom området är av stor vikt för att hitta nya hållbara källor för näringsämnen som exempelvis protein, eftersom produktionen i dagsläget för med sig många miljömässiga nackdelar. I samband med att EU godkänner insekter som livsmedel får fler upp ögonen för eventuella fördelar som de kan bidra med som råvara. Syftet med denna studien är att undersöka vilken påverkan tillsats av syrsmjöl har på färg, textur, gillande och expansion hos extruderad majskrok. Detta är ett steg i riktningen mot implementering av insekter i västerländsk kost. Genom att analysera vatten och proteinhalt i den extruderade produkten, samt mäta dess färg, textur, radiella expansion och gillande hos konsument kan insamlad data ställas mot varandra och eventuella korrelationer belysas. Resultatet från studien visar att vid högre andel syrsmjöl blir texturen kompaktare, expansionen mindre och en färgförändring sker åt det mörkare hållet. De prov med lägre andel tillsatt syrsmjöl, och därmed en bättre expansion, fick högst gillandepoäng på alla frågeställningar i ett konsumenttest. / In line with a growing world population, higher demands are put on primary producers to supply raw materials in adequate quantities. Research in the area is of great importance in finding new sustainable sources of nutrients such as protein, which presently brings with it many environmental disadvantages. As the EU approves insects as food, more people are becoming aware of potential benefits they can provide. The purpose of this report is to investigate the effect of the addition of cricket flour on the color, texture, liking and expansion of an extruded corn puff. This is a step towards the implementation of insects in the Western diet. By analyzing the water and protein content of the extruded product, as well as measuring its color, texture, radial expansion and consumer appreciation, collected data can be compared and any correlations can be shown. The results of the study show that with a higher proportion of cricket flour the texture becomes more compact, shows less expansion and a color change toward a darker tone. The samples with a lower proportion of added cricket flour, and thus a better expansion, received the highest points of liking on all the questions in the consumer test.

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