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  • 201.
    Fredriksson, Hasse
    et al.
    Royal Institute of Technology.
    Remaeus, B
    Svensson, Ingvar L
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Diffusionless Solidification of Metallic Alloys1988In: Solidification Processing: proceedings of the 3. International Conference on Solidification Processing, Sheffield, 21 - 24 Sept. 1987, London: Insitute of Metals , 1988, p. 518-521Conference paper (Refereed)
  • 202.
    Fredriksson, Hasse
    et al.
    Royal Institute of Technology.
    Svensson, Ingvar L
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Computer Simulation of the Structure Formed During Solidification of Cast Iron1985In: The Physical Metallurgy of Cast Iron: proceedings of the third International symposium on the physical metallurgy of cast iron, Stockholm, Sweden, August 29-31, 1984, New York: North-Holland , 1985, p. 273-284Conference paper (Refereed)
  • 203.
    Fredriksson, Hasse
    et al.
    Royal Institute of Technology.
    Svensson, Ingvar L
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Mechanism of Catastrophic Swelling of Cold-Bonded Pellets1974In: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 3, no 5, p. 185-192Article in journal (Refereed)
  • 204.
    Fredriksson, Hasse
    et al.
    Royal Institute of Technology.
    Svensson, Ingvar L
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    On the Mechanism of Pore Formation in Metals1976In: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 7, no 4, p. 599-606Article in journal (Refereed)
  • 205.
    Fredriksson, Kristin
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Rehnström, Astrid
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Omkonstruktion av elektrisk testrigg2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents a thesis done at Husqvarna Groups component department. The purpose was to redesign an electrical test rig for a Husqvarna chainsaws so that it was robust enough to withstand tests for at least 50 hours at a speed of 14 000 rpm. The electrical test rig is driven by an electric motor that sets the rotating system in motion.

    The current test rig is designed to demonstrate that the relevant load conditions are achieved and the next step is to redesign the test rig so that it is robust enough to cope with component testing. So far, the tests has lasted for at most 1 minute and the coupling has been creating problems for the system since it opens up during tests because of the centrifugal forces. The choice of coupling is therefore to be reviewed. In previous tests the test rig was noted to vibrate more than expected during acceleration up to 14 000 rpm. The test rig is currently rigidly fixed onto a steel table during tests and this reduce the recreation of the chainsaw natural movement. The thesis therefore includes a review of the possibility of a vibration damping system.

    Background for the choice of the coupling and vibration damping system was based on a study containing analysis of current test rig and a previous thesis done on the test rig before its development. Theories and data collection was done through literature study of relevant articles about power of transmission and vibration. Interviews was carried through with knowledgeable persons from Husqvarna with experience of test rigs. The study then continued with the development of relevant calculations and by a concept study with creation of construction criteria lists. The concept study was finished off with a Pugh’s matrix with a comparison of the concepts.  

    The result from the concept study for the coupling which was recommended was a coupling called flex shaft. This consists of a hard twisted spring and is beneficial for designs that require nonlinear transmission, are capable of tests at high speed and can transfer the desired torque. Flex shafts are specially ordered based on special criteria’s, making it suitable for structures with multiple and complex requirements. The vibration damping system recommended from calculations and the concept study consisted of four vibration damping elements of rubber. These should be attached under the aluminum plate that the test rig is fixated on. Each vibration damping element need to have a max stiffness of 20.55 N/mm and to be able to bear a weight of 6.55 kg.

    If the recommendations are followed to create a robust test rig with the flexible shaft coupling and the proposed vibration damping system testing of components and analyzes will be more easily implemented at Husqvarna. This will also help the research and development forward in both a cost and time effective manner.

  • 206.
    Fredriksson, Robert
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Trkulja, Milovan
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Fuel Efficiency in AWD-system2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project has been made in cooperation with engineers working for GM Engineering/Saab Automobile AB in Trollhättan. The given name by Saab for the project is “Fuel efficiency improvements in All Wheel Drive(AWD)-system”. The main tasks of this thesis work were to investigate the size of the power losses in different parts on the propeller shaft, to design a computer program that calculates

    coordinates and angles on a propeller shaft and to investigate the possibilities to put together a simplified formula that calculates the natural frequencies on a propeller shaft.

    The main parts of this report are a compilation of the theory about AWD and mostly about the parts on the propeller shaft, and also a description of the developed computer program called Propeller Shaft Calculator. This report doesn’t concern power losses in the different joints because there were no such general equations to be found. The most common way to calculate the power losses inside a joint is to do tests were the power loss is measured at different angles, torque and speed and then use that data to put together an approximated equation.

    Most of the work on this project has been on theory studies and on programming. The main result of the project is the program Propeller Shaft Calculator.

    Propeller Shaft Calculator is a program that is designed in Microsoft Excel. All the menus are programmed in the visual basic editor in Excel. The program is supposed to be used as a help while designing new propeller shafts.

    Propeller Shaft Calculator can calculate all the coordinates, lengths, angles and directions on a propeller shaft. It also calculates natural frequencies, plunge, estimated power loss on the second shaft and angles in the joints. In the program you can choose to do calculations on four different configurations of propeller shafts but can quite

    easy upgrade the program with more choices.

    Basically the program works like this:

    First you choose the right propeller shaft in the main menu. Then you fill out the indata sheet with coordinates, lengths, material data and so on. As you type in the input data the output data will appear in the out-data sheet next to the in-data. Every propeller shaft has also a calculations sheet were more detailed calculations can be

    found.

    The program also has a built in help function and a warning function that lights a warning sign next to the values if they are outside the limits.

  • 207.
    Fredriksson, Stefan
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Ekström, Mikael
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Datorstödd processberedning för precisionsförbättring och effektivisering av offertarbete2007Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
  • 208.
    Frid, Matilda
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Aronsson, Malin
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Utvärdering av tätningskoncept för aktuator i motorrumsmiljö2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed in association with Kongsberg Automotive AB, a subcontractor within the automotive industry who specializes in gear shifters for both manual and automatic transmission vehicles. The automotive industry is highly dynamic and constantly searching for innovative improvements. In recent years, this has led to an increase in the importance of electronics within a product. In case of an electronic failure, this can lead to devastating consequences for the function of a product. This leads to higher demands for safe encapsulation. Some sort of sealing is often used to reduce the risk of leakage and penetration of foreign particles.

    The product that has been studied in this project is an actuator. The function of an actuator is to convert electronic signals from the gear shifter to mechanical movements that interacts with the gearbox. The product consists of three sealing solutions that works together to meet the requirements for encapsulation during the vehicles lifetime. These solutions include a static gasket in form of a FIPG, a dynamic o-ring seal and a Gore-Tex vent membrane.

    The purpose of this thesis is to study and evaluate different sealing solutions that fulfills the demands of encapsulation according to the specification. Kongsberg Automotive wishes to explore if there are better sealing alternatives than the ones used today, particularly in regards to a potential increase in volume in the near future.

    In order to perform the project, an extensive literature study has been conducted. It was based on collection of facts, benchmarking, interviews and observations both within and outside of the company. This resulted in a Pugh matrix where the different sealing concepts where evaluated against the current solution, FIPG and dynamic o-rings. Criteria such as cost, production and assembly friendliness, work environment, processing time, life expectancy and the need of redesign were developed based on DFX-tools and interviews.

    The Pugh matrix were performed for both the static and the dynamic seal, using the same criteria in both cases. Based on the matrix, laser welding were chosen to be the most suitable seal for the static application. A few of the reasons were its low cost for high volume productions, the fast processing time and high function. For the dynamic seal, Kongsberg is recommended to continue using the current o-ring solution due to its low cost.

    To implement the recommended static sealing, redesign of the product is required. To achieve a successful joint, there are increased requirements for the flange surfaces, such as warpage and surface finish. In addition to this, the flanges needs a new design that enables joining. Laser welding is based on the material properties of the flanges. One part needs to be laser transparent to let the laser beam through, while the other part has to be laser absorbent to melt the material by the joint.

    This study results in a foundation for Kongsberg Automotive, to facilitate decision-making in regards to sealing design.

  • 209. Fridlund, Lennart
    et al.
    Holmgren, Dag
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Terminalbord: En sammanställning av arbetsbord för bildskärmar och tangentbord1981Report (Other academic)
  • 210.
    García Mateo, Jimena
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Kids' phone: The design of a mobile phone for children from 5 to 11 years old2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been made in collaboration with the company Tinitell in Stockholm. The purpose of the project is to design mobile phones for children.

    This report explains all the Design Process, as SVID (Swedish Industrial Design Foundation) describes it. It starts with a research phase and according to its conclusions, a concept generation phase follows. After discussing the possible concepts, the best alternative is selected and developed. The final part of the report is the analysis and conclusions of the whole process. 

  • 211.
    Garza, Simon
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Shaqiri, Lundrim
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Korrosionsstudie om nickel-krom-molybden legeringar i våt skrubber.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work is a study of materials which focus on nickel-chromium-molybdenum-based alloys used in today’s wet scrubbers. Since the requirements for emissions of sulfur dioxide is a major environmental issue, this creates a need for the use of a wet scrubber. This product is in installations where combustion engines are available and are basically in all larger vessels. The flue gas that engines emit are harmful to the environment and for that reason, the flow is absorbed into a wet scrubber where combustion takes place. The flue gas is separated by a number of sprinklers placed above of the gas in a scrubber. Collected seawater is used to separate the gas through the sprinklers that injects the water on top of the flue gas where impurities is separated from the gas that will condense out to the atmosphere. The water fluid together with the contaminants is collected on the bottom of the scrubber and into the tanks. This environment is very harmful to the material that the product is made of, in particular on the bottom where the material is more susceptible for corrosion.

    The work describes several types of corrosion and the meaning of the different types so that the reader easily can understand the impact of the environment on the alloys. The type of corrosion that occurs primarily in scrubbers is pitting corrosion and is considerate to be a highly local type of corrosion, and the most dangerous type. Pitting occurs when the protective oxide layer does not have time to repassivate and can also lead to other types of corrosion. Due to the dangerous work environment, the risk for corrosion to occur is high and therefore, focus is put on this specific material group. The purpose of this work was to study the alloys and describe them with the help of a literature study.

    Using data collected from tests previously performed in accordance with standards, the collected data has been interpreted and contributing to the evaluation of the various alloys. The basic tests used in the evaluation of the nature of the alloy are tests in which a piece of material immersed in a specific solution with different circumstances and conditions. This is not enough to ensure a sustainable life cycle for a wet scrubber and therefore, alloys is evaluated using various field tests as well. Theoretical studies on tests in aggressive environments is used to result the ranking of the various materials and also a new material is examined by the name alloy 2120. 

  • 212.
    Ghassemali, Ehsan
    et al.
    School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore.
    Jarfors, A. E. W.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    Tan, Ming-Jen
    School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore.
    Lim, Samuel Chao Voo
    Singapore Institute of Manufacturing Technology (SIMTech).
    On the microstructure of micro-pins manufactured by a novel progressive microforming process2013In: International Journal of Material Forming, ISSN 1960-6206, E-ISSN 1960-6214, Vol. 6, no 1, p. 65-74Article in journal (Refereed)
    Abstract [en]

    Microforming is defined as the process of production of metallic micro-parts with at least two dimensions in sub-millimeter range. Many of these microforming processes have been investigated in laboratory-scale, which is not suitable for industrial applications. In this work, the feasibility of producing copper micro-pins using a novel progressive microforming process is demonstrated. This process has a good potential for mass production of micro-parts. The material flow behavior and the microstructure of the formed micro-pins were investigated by means of optical microscopy and simulation. From this study of material flow behavior with respect to different process conditions (die diameter, die design and punch diameters used), it will be shown how the respective material flow behavior in the progressive forming process influenced the microstructure evolution in the formed micro-pin. It was found in the experimental results that there is a soft zone on the micro-pins surface under specific process conditions. The microhardness results were consistent with the microstructural observations. Simulation was employed to understand the material flow direction under the punch during the microforming process and evaluate the position of the neutral zone in the disk-shape head of the micro-pin produced. This understanding of the neutral zone position with relation to the metal dead-zone as well as the material flow behavior was necessary to explain the dead-zone leakage in the microstructure and the occurrence of the soft zone. By decreasing the punch to die diameter ratio, and also choosing a die without entrance fillet radius, it was shown that the soft zones at the pin surface could be either minimized or entirely removed.

  • 213.
    Granath, Olof
    et al.
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting.
    Wessén, Magnus
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Cao, Haiping
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Determining the effect of slurry process parameters on semisolid A356 alloy microstructures produced by the RheoMetalTM process2008In: International Journal of Cast Metals Research, ISSN 1364-0461, E-ISSN 1743-1336, Vol. 21, no 5, p. 349-356Article in journal (Refereed)
  • 214.
    Granath, Olof
    et al.
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting.
    Wessén, Magnus
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Cao, Haiping
    Jönköping University, School of Engineering, JTH. Research area Materials and Manufacturing - Casting. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Porosity reduction possibilities in commercial aluminium A380 and magnesium AM60 alloy components using the RheoMetalTM process2008In: Proceedings of 4th international conference High Tech Die Casting, AIM: Montchiari (Brescia), Italy 9-10 April 2008, Milano, Italy.: Associazione Italiana di Metallurgia , 2008Conference paper (Refereed)
  • 215.
    Gundstedt, Mikael
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Svensson, Rikard
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Analys av Itabs lösfot och stolpe2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    What is the most important aspect when shelves are being sold, manufactured and used? Well they must be user-friendly which means they should be easy to assemble, carry and modify. They should also be easy to ship, weight aspect and not ungainly. Most importantly it must be worth its price or just cheap, to accomplish this one should keep the amount of material to a minimum whilst the manufacturing must be easy.

    These were some of the questions at issue that this work has started from and they have more or less thoroughly been penetrated.

    In an effort to acquire some answers the possibility to reduce the thickness of the poles to the shelves from 2,5 mm to 2,0 mm, this would present partial solutions to both weight and material issues but before all the price issue though the material contributes to a large piece of the cost. This suggestion appeared when the poles were investigated and calculated from different angels to determine if they would hold out to this kind of change. The angels that were investigated are bending of the pole, the holes in the pole will be sheared (ripped like can opener-effect) by the hooks on the shelf consol and the detachable foot. The result that emerged are that some sizes of the poles can endure the change without any thought whilst the smaller poles requires some further testing and pondering before implementing. The aspect that was found to be norm setting was the bending of the pole.

    The fact that the user friendliness always can be improved a helper was designed. The helper is meant for the user is so he/she easily can see how much merchandise (weight) a shelf and pole can withstand. In other words to make sure that the shelf/pole is not overloaded and risk a breakdown.

    To declare where Itabs system is in regards to its competitor on these important questions a competitor analysis was conducted. The primary test-issues were stability, easy to assemble and if there are any apparent hazardous areas on the stand. Unfortunately there were some difficulties in retrieving the stands from some of the competitors or more importantly the stand from Itab themselves. So a comparison was not possible although they who were interested in testing their stands and had sent them in were to be pleased so a test was conducted. The issue regarding the price was not compared though this report is not meant for the users in the stores.

  • 216.
    Gustafsson, David
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Ejdehag, Mari
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Kartläggning av omställningsarbete vid formspruta2006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    This study will chart the changeover work, with a standpoint in the SMED-theory, at the company Peter Ernst AB in Värnamo. They are suppliers in plastic moulding industry and delivers to amongst other Saab in Trollhättan and Scania. The company are in a very competitive market, and they have to make manufacturing more efficient and rationalise their costs to be able to compete. A big problem, which the company has identified, is their long changeovers. It brings higher costs, a more stressful work climate and holds back the company from becoming more efficient.

    Field studies will be conducted on the changeover, which will be observed and filmed. The filming provides the possibility to go back and look at the changeovers again. The objective of the study is to map the changeover work, and also make clear suggestions for improvements.

    To give the suggestions of improvements more depth they will be discussed with the changeover workers. All the machines in the study are plastic moulding machines and are CNC-guided.

    Our study will result in a mapping of the changeover work, and some suggestions for improvements of the tool carrier and new work routine.

  • 217. Gustafsson, E
    et al.
    Hofwing, Magnus
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Simulation and Measurement of Residual Stresses in a Stress Lattice2007In: Proceedings of the the 2nd International Conference of Simulation and Modelling of Metallurgical Processes in Steelmaking, September 12-14, Austria, 2007, Leoben: ASMET , 2007, p. 285-290Conference paper (Refereed)
  • 218. Gustafsson, E
    et al.
    Hofwing, Magnus
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Simulering och mätning av restspänningar i spänningsharpor2007In: Luleå tekniska universitet, Svenska Mekanikdagar, 13-15 juni, 2007, 2007Conference paper (Other academic)
  • 219. Gustafsson, E
    et al.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Shape optimization of castings by using successive response surface methodology2008In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 35, no 1, p. 11-28Article in journal (Refereed)
  • 220. Gustafsson, E
    et al.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Structural optimization of castings by using ABAQUS and Matlab2005In: Proceedings of the Seminar on Competent Design by Castings (GJUTDESIGN -2005), June 13-14, Espoo, FINLAND,, 2005Conference paper (Refereed)
  • 221. Gustafsson, E.
    et al.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Structural optimization of castings by using Abaqus and Matlab2005In: Proceedings of the Abaqus World Users' Conference, May 18-20, Stockholm, Sweden, 2005., 2005Conference paper (Refereed)
  • 222.
    Gustafsson, E
    et al.
    Jönköping University.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Strukturoptimering av gjutgods med hänsyn tagen till gjutspänningar2007In: Luleå tekniska universitet, Svenska Mekanikdagar, 13-15 juni, 2007, 2007Conference paper (Other academic)
  • 223. Gustafsson, E
    et al.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Successive Response Surface Methodology by using Neural Networks2007In: Proceedings of the 7th World Congress on Structural and Multidisciplinary Optimization, May 21-25, Seoul, Korea, 2007Conference paper (Refereed)
  • 224.
    Gustafsson, Erik
    et al.
    Väderstad-Verken AB.
    Hofwing, Magnus
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Strömberg, Niclas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Engineering mechanics and optimization.
    Residual stresses in a stress lattice - experiments and finite element simulations2009In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 209, no 9, p. 4320-4328Article in journal (Refereed)
    Abstract [en]

    In this work residual stresses in a stress lattice are studied. The residual stresses are both measured and simulated. The stress lattice is casted of low alloyed grey cast iron. In fact, nine similar lattices are casted and measured. The geometry of the lattice consists of three sections in parallel. The diameter of the two outer sections are thinner than the section in the middle. When the stress lattice cools down, this difference in geometry yields that the outer sections start to solidify and contract before the section in the middle. Finally, an equilibrium state, with tensile stresses in the middle and compressive stresses in the outer sections, is reached. The thermo-mechanical simulation of the experiments is performed by using Abaqus. The thermo-mechanical solidification is assumed to be uncoupled. First a thermal analysis, where the lattice is cooled down to room temperature, is performed. Latent heat is included in the analysis by letting the fraction of solid be a linear function of the temperature in the mushy zone. After the thermal analysis a quasi-static mechanical analysis is performed where the temperature history is considered to be the external force. A rate independent J2-plasticity model with isotropic hardening is considered, where the material data depend on the temperature. Tensile tests are performed at room temperature, 200°C, 400°C, 600°C and 800°C in order to evaluate the Young´s modulus, the yield strength and the hardening accurate. In addition, the thermal expansion coefficient is evaluated for temperatures between room temperature and 1000°C. The state of residual stresses is measured by cutting the mid section or the outer section. The corresponding elastic spring-back reveals the state of residual stresses. The measured stresses are compared to the numerical simulations. The simulations show good agreement with the results from the experiments.

  • 225.
    Gustafsson, Joakim
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Kontroll av lyftredskap i betongindustri2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    This paper shows how instructions for the inspections of the lifting tools at Abetong were made. The most important is how the company can ensure that every lifting tool is inspected. The work was carried out at three of Abetongs factories. Abetong makes precast concrete elements, which makes them use liftingtools as a part of their daily work; most of the lifting tools are custom made for the concrete industry.

    A numeric system for the lifting tools was formed and partially implemented. A small investigation to find companies which could do the annual inspections was made. A specification for this was also written. An instruction for the daily inspection of the lifting tools was made. A signing list will be put up at each working area to ensure that the daily inspections are being done. The lifting yokes which lacks label will be risk analysed, this creates some questions about whether this is aloud.

  • 226.
    Gustafsson, Robin
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Karlsson, Alexander
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Tool Belt For Professional Forestry Workers2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report discusses different steps of the product development of a new tool belt, for the company Husqvarna Group, to be used by professional forestry workers. From identifying the customers’ needs through field studies and inter-views with different users, to a substantial solution to the problem.

    The introduction states the purpose of the report, the research questions that this report is discussing, and also the delimitations that have been made. The report is focused on finding a new and better solution than the current one to attaching holsters on the tool belt, but also how detachable braces can be attached to the belt. Husqvarna and their current tool belt, is covered along with the main com-petitors’ tool belts. Then follows a chapter with theoretical background there the QFD method and Pugh’s decision matrix are described which are later used in the report. There is also a description of how the work in the forest is being done and how the tool belt is used.

    In the method chapter a time plan is established for the project’s different phases. After that the QFD method is used along with a house of quality to identify the customers’ needs and to rank the customers’ requirements and create engineering specifications to make the requirements measureable. The house of quality in-cludes an analysis of the competitors compared to the current tool belt from Husqvarna. A number of different concepts are included to solve the two prob-lems, fastener for holsters and braces are produced and are evaluated against the set requirements with the help of Pugh’s decision matrix. A “proof of concept” prototype is then produced from the final concept.

    A summary of the opportunities for improvements on the current tool belt is dis-played in the result chapter. There is a presentation of the final concept and the corresponding prototype. The concept for attaching the holsters includes a plastic band with holes that is attached in its lower edge so it can be folded down. Behind the plastic band, and through the holes, flies from the holsters are threaded. The plastic band and the holster flies is then covered and secured by a fabric band that is sewn onto the belt in the upper end and attached to the belt with snap fasteners in the lower end.

    Finally there is a chapter with conclusions, where the methods and the results are discussed and there are suggestions on how the work should be further continued.

  • 227.
    Gustavsson, Jonas
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Kundutredning av deltagande företag i IndustriForums Lean krAft utbildning 2005-20062006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    This essay is an enquiry about how companies as participated in a Lean pro¬duction education use this education. The essay describes also how one works with the implementation of Lean production and how they believe that they will work. The enquiry tries to create an advisory material for other companies that are in the beginning of implementing their own Lean production systems. There these companies’ gets a picture of how other companies have done during their try to create a functioning Lean production system. In the essay, one may see how well the Lean concept basic thoughts and principles agree with the seven differently producing companies in the Jonkoping region. One may also see which parts from Lean production these companies use.

  • 228.
    Gustavsson, Markus
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Granskning av hur ett miljöledningssystem uppfyller kraven i SS-EN ISO 14001:20042007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose with this report is to make a contribution to Bodycote heat treatments workshop in Värnamo, how to introduce, establish and constantly improve its environmental system. The rapport will help Bodycote with there certifying in ISO 14001: s demand standard. Organizations who continuously work with environmental issues have a lot to gain. Two things an active environmental development process will convey are, building of thrust within the circle of customers, and great financial savings. An increasingly numbers of organizations realize the importance to introduce a functioning environmental system into their activity. The investment in a functional environmental system normally has a pay back time in just a few years.

    A perusal was carried out of the current documents and routines in the environmental system of the workshop. This perusal has later been presented through comments and by proposals to improvements. The result of the perusal showed that there are certain areas of the environmental system that not are properly fulfilled by the standard demands. For example the guaranteed concern for the important environmental aspects, when the system is established, introduced and supported. The problem is rooted in the lack of information documented by the organization. There shall be a list documented over the most important environmental aspects.

    Other important demands that the standard proclaim, is the comprehensive and the detailed environmental goals. These goals are not established, introduced or supported. Each environmental goal shall have an achievement plan, plans that are yet not active or documented. According to the demands in standard, the workshop shall guarantee that the measurement of environmental performance is performed in a proper way. A routine on these demands was not found during the perusal.

    The conclusion of the perusal is that the most of the criteria’s in the standard is fulfilled by Värnamo workshop. To succeed with the certifying, the workshop shall especially look at demands concerning the important environmental aspects, the comprehensive and the detailed environmental goals. These demands are vital through out the whole environmental system. However, the other demands that are not fulfilled are also important.

  • 229.
    Gyllengren, Elisabeth
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Lantz, Daniel
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Olsson, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Information ochmaterialflödesförbättrings analys2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This examination work is performed at the institution of industrial economy and production at Jonkoping technical university, for JELD-WEN Door Solutions plant in Forserum.

    Today the focus in the company is on to reduce their inventories binding of capitals as well as inventory of products and that includes to get a good control of the supply and handling of material which is of great importance.

    JELD-WEN Door Solutions is one of the worlds leading producers of windows and doors and the head-office is located in Oregon, USA.

    A great number of wooden doors are manufactured by the company in varying of constructions, classifications and performance.

    The production of the plant in Forserum has a project- and customer focus manufacturing where only internal doors are produced. The overall market they are concentrated on is to different institution such as schools, hospitals etc.

    The purpose of this work is to investigate possibilities to improvement of material- and production control at JELD-WEN. The report will handle the master production schedule to and from the production divisions within manufacturing industry. Focus will be on the way for information- and material flows from arrival, transport within the company and further on to customers.

    Further a map of the flow was performed which gave a clearer picture of the connection between the flow of information- and material for the manufacturing process. On the basis of the mapping of the flow, the group discovered that the flow of material had some improvement potential. The group has also chosen to look on the final assembling process to investigate if it’s able to do improvements here also.

    The report is concluded with discussion and suggestions of improvement considering the flow of information- and material. The suggestions of improvement that is given are suggestions that how JELD-WEN can work with the handling and the structure of material to production.

  • 230.
    Gårdenheim, Martin
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Landstedt, Alexander
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Analys av kompressorer i system 751 på Ringhals AB, block 12009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ringhals AB upplever att de har stora underhållskostnader på tre kompressorer som försörjer system 751 med tryckluft. Rapportens syfte är att ta fram ett beslutsunderlag för att kunna motivera en nyinvestering. Underlaget ska innefatta bl.a. en underhållskostnad för kompressorerna, vilka de vanligaste felen är samt en rekommendation till lämplig utbytesinvestering.

    En sammanställning av underhållskostnader har genomförts för att sedan ställa i jämförelse med en nyinvestering. Då driftsäkerheten för Ringhals AB är av största prioritet, undersöktes vilka de vanligaste felen är som uppkommer samt hur ofta underhållsinsatser krävs. Denna undersökning visade att 80 % av dagens fel kommer att försvinna helt vid en nyinvestering av skruvkompressorer.

    Arbetet har genomförts genom att undersöka de arbetsordrar på kompressorerna som uppstått under de senaste 10 åren. Ur arbetsordrarna sammanställdes vilka underhållskostnader kompressorerna har, gällande mantimmar och reservdelar, både på avhjälpande- och förebyggande underhåll. Flera mätningar har genomförts, en elmätning för att se hur elförsörjningen ser ut i de olika driftstegen hos kompressorerna samt en ljudmätning för att kunna jämföra hur ljudnivån förändras med ett investeringsalternativ. En undersökning av hur mycket administrativ tid som lagts ned på varje avhjälpande underhåll har också utförts.

    I den stora underhållskostnaden som finns idag på kompressorerna ingår det en ventilrenoveringskostnad av hög- och lågttrycksventiler. Den kostnaden skulle försvinna helt samt frigöra mantimmar om byte till skruvkompressorer sker, p.g.a. att det inte finns några sådana ventiler i en skruvkompressor.

    Två leverantörer av kompressorer kontaktades och deras offerter jämfördes sedan med hjälp av nuvärdesmetoden och en LCC- kalkyl. Den mest lämpliga investeringen för Ringhals AB är skruvkompressorer, ZR200, från Atlas Copco Compressor AB. Deras kompressorer ger en lägre livstidskostnad och ett bättre nuvärde under beräkningsperioden på 15 år. Dessa kompressorer uppfyller de krav som ställs från Ringhals och de kan kopplas direkt på nuvarande system. En investering skulle bidra med att underhållskostnaderna, för att bibehålla tryckluftssystem 751 i drift, skulle sjunka drastiskt. Det skulle också frigöras mantimmar, både hos serviceteknikerna och underhållsingenjörerna, då mindre underhåll krävs.

  • 231.
    Hall, Elin
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Rydberg, Per
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Konceptutveckling av remdriftskoppling: Kraftöverföring från fordon till redskapsrem och frånkoppling av denna2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis was initiated in collaboration with Husqvarna Rider and Semcon AB. The thesis developed concepts for automated attachment of gardening tools to the front of the ride-on mowers developed by Husqvarna Rider. These concepts aim to improve the users experience when shifting between the cutting deck and other available tools, while avoiding direct interaction with the vehicles’s belt drive. The project also researched documented information and theory regarding the construction to establish a foundation for future development of the product detail.

    The work has been carried out through pilot study, study of literature and concept study. The concept study has consisted of preparatory work, concept generation, concept evaluation and concept selection. Examples of methods used in this study are 6-3-5 brainwriting, contradiction charts, morphology and decision matrices using robust decision methodology. The study worked with a total of over 100 ideas and concepts which were reduced down to two solutions. One of these can be applied with minimal investment while the other possesses a good potential for broader future application.

    The first solution was chosen as it had the potential to improve the existing product with relatively minor modifications of the construction. The second solution was chosen as it provided a very efficient tool switch with fewer failure modes than other concepts. The second solution also had the potential of application in other products and allows remote interaction with the belt drive, resulting in improved user safety.

  • 232.
    Hallgren, Sara
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Pumpning av slam med hög TS2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sweden's largest sewage treatment plant, Henrikdal, will be rebuilt to receive twice as much sludge than they can do today. To have the ability to do that, either the level of total solids (TS) must increase or expand the rotary chambers. Off which the second option is to be avoided due to the high costs.The report will answer why the origin, viscosity, shear rate, temperature and TS-level of the sludge is important to consider when pumping it. Also, the report will show results of how the viscosity will get higher either when the TS-level or the shear rate is increasing as well as the temperature is decreasing. Beyond that, the report will contain source gathering, method, conclusion, discussion and ends with proposals for further research.

  • 233.
    Hammerin, Karl
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Werther, Adrian
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Beslutstödsmodell: För ökad effektivitet i lagermiljöer2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The globalized world has increased people’s awareness, which has resulted in a higher demand for better quality as well as shorter led times, without increasing the selling price. The fact that companies are actively working with streamlining processes of the existing business can therefore be seen as crucial for its future existence.

    In this study, a decision support model for the initial part of streamlining projects for warehouses has been developed. The model is based on key theories and methods of efficiency and warehouse layouts. This constitutes the theoretical foundation, for which the six areas of the model were designed. The model is based on a process- and rating structure, in which the six areas were broken down to 12 matrices and 1 summary. In each matrix, the solution methods are rated based on their individual properties against crucial parameters. As support for the model, complementary questions for each area have been developed, to give the user good opportunities to gather necessary information and data.

    By answering the questions and studying the matrices, the user has a good foundation to select the alternatives that fits the company’s needs. By doing this, the user will be able in a timely manner to identify the most relevant opportunities, and thus also discard those who do not possess the requested features or properties.

    This study has resulted in a model whose strength lies in its ability to allow companies, at an earlier stage, to allocate resources to the solutions that are relevant and therefore should be examined more closely. This based on the company's situation, goals and needs.

  • 234.
    Hannes, André
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Viktor, Park
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Konstruktion av matarsystem2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose – To create an innovative system that separates and facilitates feeding of small details from point A to point B without any complications. To create a system that facilitates transportation of details through an automatic measuring machine to minimize manual labor who wears the staff. The purpose of this study is not to develop a construction which is ready for production. The aim is to develop a proposed solutions to the problems experienced with the machine.

    Method – The work is rooted in the industrial PU-process where certain phases have been removed because no new product has been developed, but only a further development have been made. The pilot study was done in the form of a meeting with PEMA Metall. The meeting was to gather as much information as possible for further work. A requirement specification was drawn up in collaboration with PEMA Metall. Subsequently a schedule were issued in the form of a Gantt chart, based on the phases of the process used. An idea generation took place in the form of a brainstorming session. Then the requirements from the specification where weighted against each other by the method Pairwise comparison.

    The first concept elimination was carried out in three steps, in the first step only gut feeling was used to eliminate unrealistic solutions. In the second step an elimination matrix was used to eliminate the solutions that did not meet the given requirements. In the third step a Pugh matrix was established to eliminate the worst solutions.

    The remaining solutions were transferred into a morphological matrix to produce a number of total solutions. The total solutions were then transferred into a new Pugh matrix to produce a winning concept.

    Findings – The work resulted in a proposed solution to the two sub-problems with the measuring machine. The sub-problems comprises separating and feeding.

    The authors have developed a concept proposal that largely solves the problems PEMA Metall experiences with the machine. This proposal is not directly applicable to the machine due to that no important measurements has been taken in mind during the design work.

    Implications – The development has resulted in an efficiency increase from about one detail per second being measured to the theoretical 3.9 measurements per second depending on the selected chain.

    Limitations – There is a risk that the piston used at the input cannot work as fast as it needs without causing vibration. A solution to this problem is discussed in chapter 6.3.

  • 235.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    A mixed method for elasticity with the curl of displacements as a drilling degree of freedomManuscript (preprint) (Other academic)
    Abstract [en]

    We present a mixed method for the linearized elasticity equations with independent approximation of the curl of the displacements.The curl can be seen as a drilling degree of freedom allowing for coupling with rotating objects and the direct application of moments of force.

  • 236.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Nonconforming rotated Q1 tetrahedral element with explicit time stepping for elastodynamics2011Report (Other academic)
    Abstract [en]

    In this paper we apply a rotated bilinear tetrahedral element recently introduced by Hansbo to elastodynamics in R3. This element performs superior to the constant strain element in bending and, unlike the conforming linear strain tetrahedron, allows for row-sum lumping of the mass matrix. We study the effect of different choices of approximation (pointwise continuity versus edge average continuity) as well as lumping versus consistent mass in the setting of eigenvibrations. We also use the element in combination withthe leapfrog method for time domain computations and make numerical comparisons with the constant strain and linear strain tetrahedra.

  • 237.
    Hansbo, Peter
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Nonconforming rotated Q1 tetrahedral element with explicit time stepping for elastodynamics2012In: International Journal for Numerical Methods in Engineering, ISSN 0029-5981, E-ISSN 1097-0207, Vol. 91, no 10, p. 1105-1114Article in journal (Refereed)
    Abstract [en]

    In this paper, we apply a rotated bilinear tetrahedral element to elastodynamics in R3. This element performs superior to the constant strain element in bending and, unlike the conforming linear strain tetrahedron, allows for row-sum lumping of the mass matrix. We study the effect of different choices of approximation (point- wise continuity versus edge average continuity) as well as lumping versus consistent mass in the setting of eigenvibrations. We also use the element in combination with the leapfrog method for time domain com- putations and make numerical comparisons with the constant strain and linear strain tetrahedra. 

  • 238.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats
    Intrinsic finite element modeling of a linear membrane shell problem2012Report (Other academic)
    Abstract [en]

    A Galerkin finite element method for the membrane elasticity problem on a meshed surface is constructed by using two-dimensional elements extended into three dimensions. The membrane finite element model is established using the intrinsic approach suggested by Delfour and Zol´esio.

  • 239.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats
    Umeå Universitet.
    Locking free quadrilateral continuous/discontinuous finite element methods for the Reissner–Mindlin plate2014In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 269, p. 381-393Article in journal (Refereed)
    Abstract [en]

    We develop a finite element method with continuous displacements and discontinuous rotations for the Reissner-Mindlin plate model on quadrilateral elements. To avoid shear locking, the rotations must have the same polynomial degree in the parametric reference plane as the parametric derivatives of the displacements, and obey the same transforma- tion law to the physical plane as the gradient of displacements. We prove optimal conver- gence, uniformly in the plate thickness, and provide numerical results that confirm our estimates. 

  • 240.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Energy norm a posteriori error estimates for a continuous/discontinuous Galerkin approximation of the Reissner-Mindlin plate2011Report (Other academic)
    Abstract [en]

    We derive energy norm a posteriori error estimates for continuous/discontinuous Galerkin finite element approximations of the Mindlin-Reissner plate model. The finite element method is based on continuous piecewise second degree polynomial approximation for the transverse displacements and the rotated Brezzi-Douglas-Marini approximation,with tangential continuity only,for the rotations. This approximation enjoys optimal convergence, uniformly in the plate thickness. The a posteriori error estimates are residual based and are derived using techniques based on Helmholtz decompositions.

  • 241.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    Finite element modeling of a linear membrane shell problem using tangential differential calculus2014In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 270, p. 1-14Article in journal (Refereed)
    Abstract [en]

    We construct a new Galerkin finite element method for the membrane elasticity problem on a meshed surface by using two-dimensional elements extended into three dimensions. The membrane finite element model is established using a tangential differential calculus approach that avoids the use of classical differential geometric methods. The finite element method generalizes the classical flat element shell method where standard plane stress elements are used for membrane problems. This makes our method applicable to a wider range of problems and of surface descriptions, including surfaces defined by distance functions. 

  • 242.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering. Jönköping University, School of Engineering, JTH. Research area Product Development - Simulation and Optimization.
    Larson, Mats G.
    Umeå University.
    Larsson, Karl
    Umeå University.
    Variational formulation of curved beams in global coordinates2014In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 53, no 4, p. 611-623Article in journal (Refereed)
    Abstract [en]

    In this paper we derive a variational formulation for the static analysis of a linear curved beam natively expressed in global Cartesian coordinates. Using an implicit description of the beam midline during derivation we eliminate the need for local coordinates. The only geometrical information appearing in the final expressions for the governing equations is the tangential direction. As a consequence, zero or discontinuous curvature, for example at inflection points, pose no difficulty in this formulation. Kinematic assumptions encompassing both Timoshenko and Euler-Bernoulli beam theories are considered. With the exception of truly three-dimensional formulations, models for curved beams found in the literature are typically derived in the local Frenet frame. We implement finite element methods with global degrees of freedom and discuss curvature coupling effects and locking. Numerical comparisons with classical solutions for straight and curved cantilever beams under tip load are given, as well as numerical examples illustrating curvature coupling effects. 

  • 243.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Larson, Mats G.
    Umeå University.
    Zahedi, Sara
    Uppsala University.
    A cut finite element method for a Stokes interface problem2014In: Applied Numerical Mathematics, ISSN 0168-9274, E-ISSN 1873-5460, Vol. 85, p. 90-114Article in journal (Refereed)
    Abstract [en]

    We present a finite element method for the Stokes equations involving two immiscible incompressible fluids with different viscosities and with surface tension. The interface separating the two fluids does not need to align with the mesh. We propose a Nitsche formulation which allows for discontinuities along the interface with optimal a priori error estimates. A stabilization procedure is included which ensures that the method produces a well conditioned stiffness matrix independent of the location of the interface. 

  • 244.
    Hansbo, Peter
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Larson, Mats
    Zahedi, Sara
    A Nitsche method for a Stokes interface problemManuscript (preprint) (Other academic)
    Abstract [en]

    We present a finite element method for the Stokes equations involving two immiscible incompressible fluids with different viscosities and with surface tension. The interface separating the two fluids does not need to align with the mesh. We propose a Nitsche formulation which allows for discontinuities along the interface with optimal a priori error estimates. A stabilization procedure is included which ensures that the method produces a well conditioned stiffness matrix independent of the location of the interface. 

  • 245.
    Hariri, Bashar
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Sven, Skalleberg
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Implementering av ett verktyg för dokumentering av riskanalyser2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Machinery Directive gives a general overview of legal safety regulations that machinery must align to. Further specific safety requirements and standards for each individual components or assembly of parts must also be met in order to achieve a low safety risk.

    This work has been carried out for Rapid Granulator, currently one of the world’s largest producers of granulators. Granulators grind down plastic waste into a compact form of granules that can then be reused in the form of injection moulding.

    The purpose of this report is to propose a flexible tool for documenting the risk analysis for the granulator machinery, either by building on an existing tool or developing an entirely new one. The priority is to create a database that offers the user a clear view of the risk analysis for each component and allows data to be easily edited.

    In order to achieve this purpose and fully understand the client's needs, the following two questions have been considered:

    • How do others business perform their risk analysis and what tools do they use?
    • Which tools are best suited for Rapid Granulator AB and how is it structured?

    A tool has been selected based on a pilot study that consisted of interviews and an observation. The interviews were conducted with five medium-sized enterprises and the observation took place at Rapid Granulator AB. The pre-study phase of the supporting method literature resulted in a clearer understanding of the tool and its use.

    Authours found four different tools that can be used for documentation of risk analysis. Microsoft Access was selected as the most suitable tool to overcome the deficiencies of the previous tool. The authors have implemented features to meet the client's wishes. Features such as dropdown menu, color-coding and modulation basing are key additions that have resulted in a more flexible tool.

    The conclusion suggests that the company should exploit this Microsoft Access risk analyses database that has been designed specifically for their machinery and should consider developing the tool further.

  • 246. Harrysson, U
    et al.
    Sunnersjö, Staffan
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    FEM/BEM1990Report (Other (popular scientific, debate etc.))
  • 247. Harrysson, U
    et al.
    Sunnersjö, Staffan
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Werke, M
    Konceptkonstruktion: Formgivning, analys, visualisering1991Report (Other (popular scientific, debate etc.))
  • 248.
    Hassa, Marcus
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Eliasson, Sofia
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    FRAMTAGNING AV INSTALLATIONSKIT FÖR PROJEKTILINMÄTNINGSYSTEM2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report presents a thesis carried out on behalf of the company SAAB Training and Simulation which is situated in Huskvarna. The authors of this report are going to graduate as mechanical engineers focusing on product development and design, and this thesis should reflect the knowledge obtained during the education. The assignment, given from the company was to develop a concept of a stand that will constitute as a part of a mobile system for target practice. The reader get to follow throughout the project and can hopefully learn from the smart solutions and approaches that have arisen during the process.Today SAAB doesn’t have a mobile application in their portfolio that utilizes the benefits of their sensor measuring system, also called the LOMAH-bar. The system allows direct feedback to the shooter, which is preferred for training when the purpose is to improve the accuracy. The company’s request was a mobile stand that can be transported together with the LOMAH-bar and accessories in a box. This stand should easily get installed at a shooting range for practice and demounted just as fast after finishing the practice.In order to arrive at a final concept different methods and theories has been taken into account. To test and explore ideas several different experiments has been made and people in the surroundings has been interrogated to act as test subjects to reach a desired result. The final concept was a construction with a smart design. Simple configurations that offered the necessary functional solutions and a low amount of components made the choice fall on this particular design.The thesis gives the company a concept for a possible future product. By having access to this concept, the product can be demonstrated and shown to potential customers before the product is fully developed. This enables the company to ensure interest in the product early in the development stage.

  • 249.
    Hatami, Sepehr
    et al.
    Chalmers University of Technology, Department of Materials and Manufacturing Technology .
    Stolt, Roland
    Jönköping University, School of Engineering, JTH. Research area Computer Supported Engineering Design. Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Nyborg, Lars
    Chalmers University of Technology, Department of Materials and Manufacturing Technology.
    Optimized Selection of Processing Routes for Sintered Parts Manufacture: A Component-Oriented Approach2009In: Advances in Powder Metallurgy and Particulate Materials, 2 ( Part 13 ): Proceedings of the 2009 International Conference on Powder Metallurgy & Particulate Materials / [ed] MPIF, Princeton, N.J.: Metal Powder Industries Federation , 2009Conference paper (Refereed)
    Abstract [en]

    To stay competitive, PM manufacturers have to be able to accept a wide range of components with different features and properties. Thus, it is of utmost importance for manufacturers to adapt their common process routes to new requirements as rapidly and economical as possible. The procedure of identifying the right route among all the alternatives requires abundance of experience and knowledge and is a crucial and time-consuming decision; usually made by a team of engineers. In this study, by considering the mechanical properties and design specifications of the final component, a simple methodology is developed to aid the engineer(s) in selection of the optimum PM process route. In order to sort the possible routes according to cost, a cost estimating module has been devised. The total concept is applied to a case studyies and its accuracy has been evaluated.

  • 250.
    Haugan, Martin
    et al.
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Randowo, Mikael
    Jönköping University, School of Engineering, JTH, Mechanical Engineering.
    Utveckling och utförande av frekvensstudie vid Rapid Granulator AB2006Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    The object of this examination project is to produce a method of work sampling at Rapid Granulator AB. The aim is to perform the method at the company and evaluate if it is executable. The study is delimited to the basic construction of the 45-series in the assembly hall.

    Preparations to produce the method of the work sampling resulted in definitions of activities, a form and a product tree. Several days were spent studying the assembling to learn and understand the entirety.

    The work sampling result showed a large amount of no value adding time that was used in the assembling. Some of the activities could be reduced and we observed some problems during the assembly process. These problems were noted and are presented to enlighten the company, together with some suggests of changes, with the purpose to reduce the time of the assembly cycle and increase the productivity.

    Conclusions of the results of the work sampling are discussed at the end.

    A large amount of tables and charts, connected to preparations and results, is to be found in the appendix.

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