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  • 1.
    Absalyamova, Viktoriya
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Energy Analysis within Industrial Hydraulics and Correspondent Solar PV System Design2010Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Energy efficiency and renewable energy use are two main priorities leading to industrial sustainability nowadays according to European Steel Technology Platform (ESTP). Modernization efforts can be done by industries to improve energy consumptions of the production lines. These days, steel making industrial applications are energy and emission intensive. It was estimated that over the past years, energy consumption and corresponding CO2 generation has increased steadily reaching approximately 338.15 parts per million in august 2010 [1]. These kinds of facts and statistics have introduced a lot of room for improvement in energy efficiency for industrial applications through modernization and use of renewable energy sources such as solar Photovoltaic Systems (PV).The purpose of this thesis work is to make a preliminary design and simulation of the solar photovoltaic system which would attempt to cover the energy demand of the initial part of the pickling line hydraulic system at the SSAB steel plant. For this purpose, the energy consumptions of this hydraulic system would be studied and evaluated and a general analysis of the hydraulic and control components performance would be done which would yield a proper set of guidelines contributing towards future energy savings. The results of the energy efficiency analysis showed that the initial part of the pickling line hydraulic system worked with a low efficiency of 3.3%. Results of general analysis showed that hydraulic accumulators of 650 liter size should be used by the initial part pickling line system in combination with a one pump delivery of 100 l/min. Based on this, one PV system can deliver energy to an AC motor-pump set covering 17.6% of total energy and another PV system can supply a DC hydraulic pump substituting 26.7% of the demand. The first system used 290 m2 area of the roof and was sized as 40 kWp, the second used 109 m2 and was sized as 15.2 kWp. It was concluded that the reason for the low efficiency was the oversized design of the system. Incremental modernization efforts could help to improve the hydraulic system energy efficiency and make the design of the solar photovoltaic system realistically possible. Two types of PV systems where analyzed in the thesis work. A method was found calculating the load simulation sequence based on the energy efficiency studies to help in the PV system simulations. Hydraulic accumulators integrated into the pickling line worked as energy storage when being charged by the PV system as well.

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  • 2.
    AL-Shareefi, Hussein
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Neutral network corrosion control by impressed cathodic protection2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
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  • 3.
    Alzén, Axel
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Effektivisering av en produktionsprocess: Analys och förbättringsförslag till en verkstadsindustri2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Isakssons AB is the manufacturer of custom-designed products and efficient solutions in stainless steel, constructional metalwork and environmental technology. The company is currently going through an expansion phase, which leads to greater requirements for the production. In order to cope with this expansion, they have chosen to rebuild their premises, and these changes must be adapted for the production to enable further growth for the company.  The purpose of this study is to give improvement proposals to a more effective production process at a manufacturing company with varying products. In order to create understanding for the process, flowcharts, process mapping’s and time studies have been executed. By performing a zero state analysis, improvement opportunities have been discovered, and changes have been proposed from these.  The results from the frequency studies show that the operators spend a lot of time on work that is non valuable for the product. By creating more workstations for manufacturing and introducing visual workplace aids, these non valuable activities can be reduced. Furthermore, the re-locating of machines and inventory have been suggested, in order to create an easier flow through the premises.

  • 4.
    Anderson, Mats
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Artursson Wissa, Ulrika
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Avdic, Anders
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Oom Gardtman, Ulf
    Dalarna University, School of Education, Health and Social Studies, Education.
    Skogbergs, Anna
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Formativ feedback i högre utbildning: Inventering, förslag och organisatorisk implementering2018Conference paper (Other academic)
  • 5.
    Anderson, Mats
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Artursson Wissa, Ulrika
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Avdic, Anders
    Dalarna University, School of Technology and Business Studies, Information Systems.
    Oom Gardtman, Ulf
    Dalarna University, School of Education, Health and Social Studies, Education.
    Skogbergs, Anna
    Dalarna University, School of Technology and Business Studies, Graphic Arts Technology.
    Formativ feedback i högre utbildning: Inventering, förslag och organisatorisk implementering2018Report (Other academic)
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  • 6.
    Andersson, Carolin
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Från oljehydraulik till vattenhydraulik: Utveckling av ett portabelt hydraulikaggregat2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report describes the work behind the development of a portable water hydraulic system that will be used to open and close a floodgate if the regular hydraulic system used for this is inoperative. The aim was to achieve the same performance as a portable oil hydraulic system, which could be achieved with the exception that oil could not be avoided completely.

    The project was carried out in collaboration with Mobin Hydraulic AB, which develops hydraulic systems for opening and closing floodgates. Mobin specializes in water hydraulics, which is a more environmentally friendly alternative compared with oil hydraulics. As an interest was also on the market where eco-friendly solutions were increasingly demanded, the portable water hydraulic system was of interest to both Mobin and the market.

    The problems were about how the flow was to be controlled and what pump and hydraulic engine could be used in the system. The components would be adapted to water and harmonize with a predetermined petrol engine while delivering desired performance.

    By studying hydraulics and water properties and impact on the hydraulic system in combination with taking part in Mobin's experience, an image of the system's structure and components was created.

    Based on a component search, calculations and design of concepts a concept selection was made where the selected components, component dimensions and placements in the system were displayed. Due to the limited availability of water hydraulics components, gearboxes were used to get the right speed and torque. One of the gearboxes contained oil and therefore it was not possible to completely avoid oil use.

  • 7.
    Andersson, David
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Effektiviserad balresthantering2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Arctic Paper Grycksbo is a company that produces paper. The pulp which is used to produce the paper is purchased. The pulp arrives to Arctic Paper in bales which are wrapped with something called wrapping paper. The wrapping paper is similar to the pulp inside of the wrapping, which means it can be used to produce paper. Damage on the bales due to transportation and handling leads to usable pulp being removed from the bales which falls to the ground. The pulp which is removed from the bales remains on the ground (pulp rests) until workers pick it up and place it in a recycling container. This container is then to be emptied and the pulp recycled, if the procedure is working as intended.

    The current recycling procedure has proven to be in need of improvement. This has led to a need of an improvement, either by improving the method/procedure to recycle the pulp, or through preventing the pulp being removed from the bales in the first place. The purpose with this thesis is to investigate- and suggest solutions to which possibilities for improvements there is.

    An investigation of which alternative to achieve this improvement is the better- and calculations of the annual recycling potential has been done. Different concepts has then been generated based on information gathered from the investigation and calculations.

    A new way of handling the pulp which is to be recycled has been suggested in consultation with technicians from Arctic Paper. The suggested new method/procedure enables easier recycling in terms of manual labour and reduces the total costs of the procedure.

  • 8.
    Andersson, Grober
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Framdrivningssystem för Articulated Funiculator i SL deep station: Framtagning och urval av koncept2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out in collaboration with Tyréns project Articulated Funiculator developing emerging vertical transport which in this case is meant to be used in SL deep station in Stockholm.The aim of this work is to is to develop propulsion concepts for Articulated Funiculator and through concept selection sort out the optimum for SL deep station. To achieve the purpose, studies have been undertaken of literature and reports followed by workshops and customer surveys. Then a pairwise comparison has been made, QFD, concept generation and a two-stage concept selection made.Result is that the optimum propulsion system for SL deep station in Stockholm is a system of linear motors mounted between the tracks.

  • 9.
    Andersson, Martin
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Konceptutvärdering av gjutformshantering: Utformning och dimensionering av entresolplan enligt eurocode2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ABB Components in Ludvika manufactures bushing for transformers. During the manufacturing, several steel molds are used. The molds are stored on a steel mezzanine floor constructed by several columns and beams. Due to that the amount of these molds has increased the existing way to handle and store these molds is impaired based on a safety and effectivity perspective. ABB have received two concept that propose how these problems could be solved. One is based on a solution with a special floor made of spheres. The other one is from a company called ELE Engineering AB that proposes a conveyor belt that is attached to the underside of the mezzanine floor. This will enable for 60 new molds to be stored. This work aims to evaluate how the mezzanine is affected by the weight of the new molds, how it should be strengthened and to evaluate which of the concept is recommended.

    Based on a series of simulations it is suggested that the mezzanine floor is reinforced with 21 new beams and 5 pillars to cope with the stresses the molds give rise to. The European standard EN-1090 has been the basis for how these columns and beams should be designed and attached. Further the two concepts will be evaluated based on effectivity, price and safety. Based on a concept evaluation ELEs solution is recommended despite lack of information about the floor with spheres.

  • 10.
    Argårds, Andreas
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Kartläggning av ytjämnheten efter kallvalsning för olika kallvalsade kvalitéer samt trimvalsningens påverkan på ytjämnheten2010Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syftet med detta arbete är att kartlägga ytjämnheten på stålbanden efter kallvalsning samt hur den erhålla ytjämnheten påverkas av trimvalsningen. Detta för att undersöka om det är möjligt att minska ner användandet av någon valsyta i Tandemverket vid SSAB Borlänge. Genom att mäta ytjämnheten på stålband av olika kallvalsade kvalitéer efter kallvalsning och trimvalsning, mäta ytråheten på texturerade valsar före och efter användning samt genomföra test med nya ytkombinationer har ett antal resultat genererats. Två test där Docol 200 band som skulle levereras med bandyta 23 valsades med en grövre yta i Tandem (valsyta 48 istället för 34) än vad som är brukligt och sedan trimvalsades med ordinarie valsyta visade att det är möjligt att klara kraven på Ra-värde för bandyta 23 även på band som kallvalsats med en grövre valsyta än i vanliga fall. Dock är det inte säkerställt att kraven för yta 23 alltid kan uppnås på band kallvalsade med grövre valsyta. Trimvalsning med valsyta 57 i den kontinuerliga glödgningslinjen har ingen betydande påverkan på ytjämnheten för Docol 600 & 800 DP, dock påverkar den ytan för Docol 200 eftersom att dessa band har mindre spridning i Ra-värde efter trimvalsning jämfört med innan. Trimvalsning med valsyta 57 höjer toppantalet på bandens yta. Band av en högre hållfasthetsklass får lägre Ra-värde jämfört mot mjukare stålsorter. Band med stor tjockleksreduktion i Tandem får lägre Ra-värde, detta gäller speciellt Docol 200 där trenden är tydligast. Ra-värdet på de texturerade valsarna i Tandem sjunker mycket i början när de används, test har visat att redan under kalibreringen kan Ra-värdet minska med 0,8 µm – 1,3 µm.

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  • 11.
    Awda, Fadi
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Omkonstruktion av luftkylning för enfasreaktor2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The task of this thesis was to review the failure of three reactor units that were caused by

    moisture and dirt that entered the reactor through the cooling system. The purpose was to find

    a solution that would allow the reactor to stay on site without being affected by moisture or

    dirt.

    The company did not have resources to provide a quick solution for the project and therefore

    time and money is a big factor. The specifications from the customer strictly forbid any

    assemblies outside of the site and that nothing in their surroundings are affected by the work.

    To come to a conclusion the reactor had to be broken down to pieces and after that concepts

    were made to affect the environment around the reactor or the design.

    The safety that the customer requires is that the cooling equipment should be at least as

    efficient as the current one and that we make sure that this type of failure will not be repeated.

    The problem was solved by adding a temperature device that measures the heat in the reactor

    that controls the fan and redirects the airflow inside the reactor through redesign to make sure

    that moisture and dirt won't occur inside the reactor – to avoid internal flash over.

  • 12. Bergdahl, Anders
    et al.
    Kenger, Patrik
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Onori, Mauro
    The use of DFA/DFAA Analysis for early start up of Assembly System Design2005In: International Forum on Design for Manufacture and Assembly, Providence - Warwick, Rhode Island, USA, 2005Conference paper (Refereed)
    Abstract [en]

    Assembly system design and development is still characterized by uncertainty resulting in increased lead-times in the design and development process and ineffective assembly system solutions. One important reason for this situation is that companies do not use methods for assembly system design and development in the extent needed, simply because there are no methods applicable. Methods developed by academia are still too complicated and not distinct enough, in quantifiable means, concerning the link to assembly system design. In this research four case studies in four different companies have been executed with the objective to find out more about how industry handles assembly system design and if there are possibilities for improvement. The findings in the case studies unambiguously point out that there is a need for a guideline supporting the assembly system design, development and re-design phases. The case studies do also indicate that the information from DFA/DFA2 analysis, valuable for the assembly system design process, is not used within the subsequent assembly system design phase. An assembly system design guideline that uses information and results from the DFA work, together with internal and external demands, would facilitate the assembly system design and development process. This paper will introduce a framework for such a method.

  • 13.
    Byron Carlsson, T
    et al.
    KTH, Superseded Departments, Production Engineering.
    Eskilander, Stephan
    KTH, Superseded Departments, Production Engineering.
    Johansson, Roger
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Peterson, P
    KTH, Superseded Departments, Production Engineering.
    A Flowchart Method for Design For Automatic Assembly1998In: International Forum on DFMA, 1998Conference paper (Other academic)
  • 14.
    Byron Carlsson, T
    et al.
    KTH, Superseded Departments, Production Engineering.
    Eskilander, Stephan
    KTH, Superseded Departments, Production Engineering.
    Johansson, Roger
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Peterson, Per
    KTH, Superseded Departments, Production Engineering.
    A structured set of concrete rules for design for automatic assembly1998Conference paper (Other academic)
  • 15.
    Caron, Simon
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Accelerated aging of thick glass second surface silvered reflectors under sandstorm conditions2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Concentrated solar power systems are expected to be sited in desert locations where the direct normal irradiation is above 1800 kWh/m2.year. These systems include large solar collector assemblies, which account for a significant share of the investment cost. Solar reflectors are the main components of these solar collector assemblies and dust/sand storms may affect their reflectance properties, either by soiling or by surface abrasion. While soiling can be reverted by cleaning, surface abrasion is a non reversible degradation. The aim of this project was to study the accelerated aging of second surface silvered thick glass solar reflectors under simulated sandstorm conditions and develop a multi-parametric model which relates the specular reflectance loss to dust/sand storm parameters: wind velocity, dust concentration and time of exposure. This project focused on the degradation caused by surface abrasion. Sandstorm conditions were simulated in a prototype environmental test chamber. Material samples (6cm x 6cm) were exposed to Arizona coarse test dust. The dust stream impacted these material samples at a perpendicular angle. Both wind velocity and dust concentration were maintained at a stable level for each accelerated aging test. The total exposure time in the test chamber was limited to 1 hour. Each accelerated aging test was interrupted every 4 minutes to measure the specular reflectance of the material sample after cleaning. The accelerated aging test campaign had to be aborted prematurely due to a contamination of the dust concentration sensor. A robust multi-parametric degradation model could thus not be derived. The experimental data showed that the specular reflectance loss decreased either linearly or exponentially with exposure time, so that a degradation rate could be defined as a single modeling parameter. A correlation should be derived to relate this degradation rate to control parameters such as wind velocity and dust/sand concentration. The sandstorm chamber design would have to be updated before performing further accelerated aging test campaigns. The design upgrade should improve both the reliability of the test equipment and the repeatability of accelerated aging tests. An outdoor exposure test campaign should be launched in deserts to learn more about the intensity, frequency and duration of dust/sand storms. This campaign would also serve to correlate the results of outdoor exposure tests with accelerated exposure tests in order to develop a robust service lifetime prediction model for different types of solar reflector materials.

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  • 16.
    Dahlblom, Linus
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Utveckling av infästningsplattor för montering av solpaneler på tätskiktstak2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Solar panels are becoming more and more common. Unfortunately, there are currently no solutions adapted to secure the panels on membrane roofs. Instead, they are attached with methods that are meant for personal safety, which are oversized for the purpose. In this work a mounting plate that is adequately sized for mounting solar panels is developed. This is done using a product development process that is designed to define the loads on the panels and from there develop a solution which is shaped and sized for the purpose. The result is a product that withstands the loads with a good margin to a considerably lower price than the original solutions.

  • 17.
    Darth, David
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Värmehantering - Datorstödd dimensionering av kapsling för batteriladdare2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis-work, the possibility of integrating a heat sink in the encapsulation of a batterycharger has been investigated. To manage the thermal load, a plate-finned heat sink has been dimensioned. Two design concepts have been developed, with two different heat sinks integrated in the design. The concepts thermal performance has been simulated in Solidworks Flow Simulation to identify surface-temperatures, component-cooling, flow conditions and radiation. The results from the calculations and the simulations shows that both of the concepts, at an ambient temperature of 30ᵒC, performs a sufficient heat flux to keep the internal components under 93ᵒC. The battery-charger’s encapsulation temperature would not exceed 54ᵒC under these conditions. For further development, a concept with the heat sink covered by a “lid” has been recommended.

  • 18.
    Domkin, Konstantin
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Physically based models of metal plasticity2003Licentiate thesis, monograph (Other academic)
  • 19.
    Edbom Matsson, Elias
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Development of external rotation lock for center section2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Dellner is a company with many years of experience in the rail industry and provide train connection systems. The headquarters is located in Vika, Sweden where the focus is on couplers engineering, assembly and aftermarket service. A train coupler consists of several subsystems and this investigation will focus on an external rotation lock located below the subsystem center section. The external rotation lock consists of a guide rail locking the rotation. However, there are some issues with the guide rail.This investigation will study the external rotation lock and apply a concept development process, based on theory by Ulrich & Eppinger (2012), in order to develop new conceptual designs for the current external rotation lock, given the issues.The results include six 3D-designed concepts which are described and then compared via a concept screening which Dellner can decide whether to continue with the highest scored concept or further improve, revise and combine the concepts before selecting a single concept to make a detailed design and set the final target values.

  • 20.
    Edlund, Johan
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Utveckling av en variabel oljepump för tävlingsmotorer2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Racing engines often use dry sump lubrication systems in which pumps supply oil to and fromthe engine via an external tank. Dry sump pumps consist of several separate displacement pumpstages that are driven by the crankshaft of the engine, usually via a reduction gearing. Asignificant portion of the power taken from the crankshaft by a dry sump pump is due to thepump stage force feeding the engine with oil from the external tank due to the supply pressurerequired by the engine. So if the power required to drive the pressure stage could be reduced itwould have a large impact on the total power used by the dry sump pump. One way to reduce thepower used by an oil pump is to replace the regular displacement pump with a pump having avariable displacement. Since the oil pump is driven at a speed that is proportional to the speed ofthe crankshaft the pump has to be dimensioned with a high displacement to provide adequate oilflow and pressure at low engine speeds leading to a pump that is oversized at high engine speeds.Normally the excess capacity of the pump at high speed is dealt with by a pressure relief valve,but this does little to reduce the power used by the pump. While variable displacement pumpsare becoming more and more common among production engines having a wet sump none haveso far been used in a dry sump lubrication system for a racing engine. With a racing engine acompact size and low weight are important, particularly when regulations mandate the maximumsize of the pump such as in NASCAR. To fit with NASCAR regulations and it’s 3.5 x 3.5 x 10inch maximum dimensions a variable vane pump using a tilting cam ring to control displacementwas selected as a replacement for the gear pump with pressure relief. While the standaloneprototype met the 3.5 x 3.5 inch requirement, the pump stage was longer and heavier than thegear pump it was supposed to replace.

  • 21.
    Efraimsson, Kim
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Development of foldable center section for train coupler2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To safely convey trains in an urban area, a number of factors must be considered. One of these is that parts pointing out from the cart may cause harm to people or the train’s surroundings. An example of such a part is the train coupler located in the front or back of the cart. To avoid this problem, train couplers with the ability to be folded and hidden behind a hatch on the cart are used. To fold the coupler, a center section with a folding joint and locking mechanism is used.

    The main problem with existing foldable center sections is that over time, a play develops in the joint and locking mechanism as a result of wear damages. The play enables the coupler to move in an undesirable fashion which causes, among other things, the train ride to be unpleasant for passengers.

    The purpose of this project was to develop a new concept for a foldable center section which aims to reduce or eliminate the wear damages and play mentioned above. This report describes the development process, which theories were used, which methods were used and the final result of the project.

    The result of the development project is a concept for a new variant of foldable center section with associated 3D models, overview drawings and a validation plan for a finished prototype. The developed concept differs from existing solutions in many ways. The goal to reduce wear damages and its consequences was achieved with the new concept. However, the result is not optimal. This is discussed in the conclusion of the report.

  • 22.
    Elemam, Aboubker
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Development of a ESES Solar Thermal Lab on Full Scale System2011Independent thesis Advanced level (degree of Master (One Year)), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    The main aim of this project is to develop an ESES lab on a full scale system. The solar combisystem used is available most of the time and is only used twice a year to carry out some technical courses. At the moment, there are no other laboratories about combisystems. The experiments were designed in a way to use the system to the most in order to help the students apply the theoretical knowledge in the solar thermal course as well as make them more familiar with solar systems components. The method adopted to reach this aim is to carry out several test sequences on the system, in order to help formulating at the end some educating experiments. A few tests were carried out at the beginning of the project just for the sake of understanding the system and figuring out if any additional measuring equipment is required. The level of these tests sequences was varying from a simple energy draw off or collector loop controller respond tests to more complicated tests, such as the use of the ‘collector’ heater to simulate the solar collector effect on the system. The tests results were compared and verified with the theoretical data wherever relevant. The results of the experiment about the use of the ‘collector’ heater instead of the collector were positively acceptable. Finally, the Lab guide was developed based on the results of these experiments and also the experience gotten while conducting them. The lab work covers the theories related to solar systems in general and combisystems in particular. 

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  • 23.
    Eling, Christofer
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Utvecklingsarbete av tät-kapsling2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the development work of a tight enclosure of electronics for a charger. The development work is based on exchanging the technology for joints to increase the possibility of recycling the plastic. In the development work, methods and theories have been applied to create ideas, convert them into concepts that meet the customer's requirements, then print them out in a 3D printer. These prototypes are then analysed through simple assembly and disassembly tests but also simpler water resistance tests. To generate ideas around the problem, the TIPS method was used then brought throughout the development work. The ideas got converted into prototypes using methods such as customer requirements identification, pairwise comparison, product characteristics generation, target value as guidelines, QFD House of Quality, concept generation. To be print out in a 3D printer, the concepts needed to be drawn in the CAD program Solidworks. When the prototypes were printed, the analysis showed that two of the concepts showed potential and recommends further development work.

  • 24.
    Emanuelsson, Simon
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Kartläggning av breddkontraktion och förbättring av breddkontraktionsberäkning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At the continuous annealing line at SSAB in Borläge there are problems with sheet width not meeting customer requirements caused by width contraction during the annealing process. Difficulties lies at handling contraction variation and the extent to how the processes is contributing is unclear. Mathematical formula estimates the value of the contraction and preventive witdh is added at earlier process step. Newly installed equipment enable mapping of how diffrent plate dimensions and steels are affected. Investigations show correlation between plate thickness and witdh contraction but clearly influence from high annealing temperatures. Comparison of calculated and actual value for width contraction indicates the necessity of complement to how formula handle sheet thickness. Applying mathematical functions forms a new replacement plate thickness dependent term that raises the calculations within the plate thickness range. Along with factor experiments, the new term reduces differences between calculated and actual width contration for examined sheet, indicating that improvement to the mathematical formula has been achieved.

  • 25.
    Engström, Fredrik
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Ökad tillgänglighet i maskiner för skärande bearbetning2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this work is to develop principles for an approach that can continuously increase the availability of the company's machines. By studying the theory of this subject, measurements has designed to produce what the companies availability is in their four main machines. The approach shown in this work is based on three different parameters that affect the value. It is production dependent stop, maintenance dependent stop and resource shortages. By doing this way, the company can be able to have a clearly arranged data to work with, which they easily can see how to enhance availability. It has also been raised a little bit about the reliability and the mean down time where it is also possible to obtain facts to increase availability. What this work have come to is that it can be very different things that affect availability negative but by doing it this way they can see these things and put into action after that.

  • 26.
    Erixson, Gunnar
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Kenger, PatrikDalarna University.
    Proceedings from the 2nd seminar on Development of Modular Products: December 13-14, 2004, Campus Framtidsdalen, Dalarna University, Sweden2004Conference proceedings (editor) (Other academic)
    Abstract [en]

    Companies are focusing on efforts increasing the overall efficiency at the same time as the ability to meet customer needs becomes even more important. There is a need to improve the organisation and the product design at the same time through the visualisation of how a product family design should be performed in order to adapt to customers, company internal issues, and long-term strategy. Therefore, there is a need for qualified personnel in today’s companies with the knowledge of product development and modularity. The graduate course Development of Modular Products at Högskolan Dalarna has the objective to provide such knowledge. As a part of the course, each student will individually perform extensive research within a chosen area with respect to Product Development and Modularity. This proceeding is the result of the students own work and was presented during a two day seminar at Dalarna University. The contents of the papers cover many areas, from the identification of customer needs to cost effective manufacturing, and benefits of modularisation. The reader of this proceeding will not only benefit from many areas within Product Development and Modularity but also from the colour of many cultures. In this proceeding, students from nine countries are represented (Bangladesh, China, Costa Rica, Germany, Holland, India, Luxembourg Nigeria, and Sweden). Enjoy the reading.

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  • 27.
    Fahlvik, Adam
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    3D-skrivare för prototyptillverkning i plast 20162016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis project has been to investigate which new 3D printing equipment

    would be of greatest use for the company Dalelven Produkutveckling AB.

    Through interviews with the company's project leaders the company's needs for new equipment has been identified.

    Information about 3D printers, processingmethods and perihpal equipment has been gathered and sorted. With the support of theories from Quality Function Deployment 3D printers have been evaluated and sorted in categories in accordance with the company's needs.

    Dalelven need to be able to create prototypes in several kinds of plastic. In comparison between the most interesting 3D printers Stratasys polyjet printers from their Objet Connex series got the highest score (exluding HP's “Multi Jet Fusion” printers that not yet are for sale).

    In a comparison between 3D printers that print with thermoplastics it was observed that a couple of relatively unknown companies is producing 3D printers with in some categories better specifications than the established companies alternatives.

  • 28.
    Fakih, Abdullah
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Undersökning av rullfriktionsplanetväxel: Undersökning i FEM och framtagning av dimensioneringsverktyg2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work is about improvement analysis of a planetary gear. The gear is affected by the friction between the planetary roller and the sleeve. This means that there are no cogs on the wheels, but the rotating parts of the planetary gear are completely round. The friction occurs after the shrinkage of a sleeve on three planetary rollers that is seated in a planetary holder. A company in Smedjebacken uses the planetary gear in their electric hybrid system and during the test run, the planetary gear has failed. The company has carried out an investigation into the cause of the accident and concluded that the sleeve becomes oval after the shrinkage which causes imbalance of the future gear at high speeds. I was commissioned to investigate how the sleeve is affected after the shrinkage and the production of a dimensioning tool that is based on Excel for an improvement proposal for the sleeve.

    The approaches that have been used to fulfill purpose are the gathering of information consisting of interviews and information on the parts of the planetary gear. Furthermore, literature research was carried out to obtain a comprehensive picture of the problem and own studies of the existing sleeve.

    The method has been divided into two parts. Firstly, the examination of the sleeve in the finite element method (FEM) and secondly determine how the structure of the dimensioning tool should be designed. The design tool structure consists of three sheets in Excel program. The first sheet introduces and explains how it works. The second sheet is static calculations that show how the forces act in the sleeve depending on the angle. The last sheet contains Calculations that are based on Hertz's surface pressure. Future work can be the improvement of dimensioning tools and a wider investigation into the cause of the failure of the planetary gear in the hybrid system.

  • 29.
    Folmerz, Mattias
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Oljeläckage torkparti PM12: Utvärdering av oljeläckage i torkparti PM122017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Stora Enso Kvarnsveden is a paper mill located at Dalälven in Kvarnsveden. The utility currently has two producing machines, and this study deals with one of them, which is PM12. At PM12 there is a problem with oil leaks in the machine's drying section. Leakage occurs through the bearing houses who are there to support the dryer's rollers. In this study, it has been investigated what the leakage is due to focusing on its bearing seals.

    The purpose of this study has been to investigate why leakage occurs and to generate concepts to reduce or eliminate leaks. The study has included various measurements and investigations to address the problem. A literature study has been conducted to identify causes and solutions. Concepts have been generated from the literature study as well as the measurements that have been taken.

    After this study it´s not fully realized why the leakage occurs, but it had come a long bit on the way. Proposals for continued work have been given, where it is recommended more specifically what kind of measurements that should be done and the concepts that should be further developed.

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  • 30.
    Forsberg, Elin
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Undersökning: kostnadsreducering av Komponent2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This investigation is made in cooperation with a manufacturing company making machines for the foresting industry. The Company is of the opinion that a Component of these machines has a manufacturing cost that is too high, which in turn brings a risk of customer buying similar components manufactured by competing companies to The Company. The Company’s Components is today manufactured by a subcontractor, The Subcontractor. This work began with an investigation of the individual parts of The Component and case studies of the manufacturing process. Further on where suggestions of how to affect the manufacturing costs defined; integration of parts, standardize components, analyse of different ordering volume, and elimination of process steps in the manufacturing process. These actions effect of the manufacturing costs were then examined and compared. The result of this work has not generated cost reductions of The Component that would make The Company competitive on the market of The Component. However the work have generated suggestions on other alternatives that The Company can continue working with to reduce the manufacturing costs of The Component.

  • 31. Ginsburg, Alexander
    et al.
    Börjesson, Fredrik
    Erixon, Gunnar
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Size Ranges in Modular Products - A Financial Approach2004In: The 7th Workshop on Product Structuring – Product Platform Development, Chalmers University of Technology, Gothenburg, 2004Conference paper (Refereed)
  • 32.
    Hagfalk, Peter
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Omkonstruktion av handmanöver2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A thesis has focused on the redesign of a manual hand maneuver for pneumatic valve actuators. The manual maneuvering ability has been expensive in relation to competitors, which has meant that the company often loses procurement. This has led to a desire to make it cheaper. The hand maneuver is not only sold mounted from scratch but is also available as a conversion kit. Such a conversion kit has been disassembled to get an understanding of how it works. A cheaper variant of hand maneuver with different functions has also been analyzed and served as a source of inspiration and reference when new concepts have been developed. By applying item reduction, the number of components involved has been reduced.  The number of items in the new concepts has been reduced compared to the expensive hand maneuver, which contributes to a lower production cost. One concept has been selected to further develop. Since then, details have been dimensioned in more detail and a risk analysis has been carried out. With the help of the article reduction, many items have been excluded and the new product developed is more like the cheaper variant but has been given the same functions as the expensive variant. This provides the conditions for completely replacing the expensive hand maneuver and therefore reducing the number of item numbers that the company works with.

  • 33.
    Hansson, Fredrik
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Tillämpad motoroptimering: Optimering av tillämpad BLDC-motor2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report contains a description and analysis of a particular type of engine that is optimized for an electric single-passenger vehicle. Work is based on the existence of a developed prototype of the vehicle and also the engine but it cannot be considered to be sufficiently optimized for the purpose. The goal and the purpose of this report is to investigate the prototype's limitations and shortcomings and what specific target values are determined to be, if possible fulfilled. These are then used to analyze and develop an improved design.

    Specific software have been used to help in the work to make a model in 3D CAD and also to simulate the performance of a theoretical model. The accuracy of the simulated model cannot be verified as no real model has been constructed. The simulated model shows that there is great opportunity to improve performance while the design has been made smaller and lighter. The creation of a 3D CAD model also allowed that strength analyzes have been done on selected components that can be considered to be highly stressed. Thus, the structure has also been verified that it can work for the intended use without a risk of breakdown or wear out prematurely.

    Finally, an estimate of the cost of manufacturing was made that's very simplified but still provides an indication of how much it might be. The calculation is based on the values that the software generates by the input of material prices. To help further, a local company was contacted for a quote in order to provide a more accurate result. Then, it is only a rough estimate and since there is not an existing production line available there will be an estimated value. The estimated cost is still within reasonable values but it can still be improved. There is potential to optimize the cost and also the design further, but the aim of this work was to develop a product that meets the requirements which was fully achieved.

  • 34.
    Hassling, Magnus
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Löppönen, Pauli
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Simulering av olika underhållsstrategier inom processindustri2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syftet med detta examensarbete är att utvärdera om simulering av flöden på en emballeringsavdelning kan vara till hjälp för att kunna planera in stopp av packmaskiner så att förebyggande underhåll kan utföras. Med hjälp av simulering har kölängder, kötider och beläggningsgrader hos emballeringsavdelningen kunnat predikteras. Genom att skapa olika hypotesgrundade scenarion i simuleringsmodellen har ett antal resultat genererats. Resultaten av simuleringarna har gett värdefull information till underhållsavdelningens planerare. Informationen bör kunna vara ett viktigt beslutsunderlag för att kunna avgöra vid vilka tillfällen som de planerade stoppen kommer att ge upphov till minst störning av driften. Arbetet har visat att simulering av flöden är ett bra hjälpmedel för att kunna planera in stopp för förebyggande underhåll. För att kunna uppfylla syftet har en simuleringsmodell skapats över emballeringsavdelningen. Genom studier av processer och genom informationshämtning från kunnig personal har en användbar modell kunnat skapas. Även studier av underhållsteorier och simuleringslitteratur har varit till hjälp för att kunna uppfylla syftet med detta examensarbete. De utförda analyserna bygger till stor del på rekommendationer hämtade från den simuleringslitteratur som studerats men även på tips och stöd från författarnas handledare som har lång erfarenhet inom området.

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  • 35.
    Holmberg, Tommy
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Utformning av ett standardbibliotek: Fundament- och apparatkombinationsoptimering vid en HVDC-station2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis objectives was to assist with general optimizations and efficiency improvements regarding the development of an HVDC station. Through the optimization of work methods and the clarification of calculation document my thesis will show the possibility to free resources directly from the quotation and project stages. This methods has great potential to be applied to many of the future HVDC-projects that the company has the opportunity to win, and with the implementation of the LEAN tool: Continuous improvements, the methods have the future opportunity to be even more efficient.

  • 36.
    Huld, Peter Mattias Pawel
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    CE marking of a lifting beam2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rotork is a company stationed in Falun municipality, Sweden and manufactures electric valve actuators. This thesis will investigate one of their lifting beams used in daily production. Although already being used for more than 10 years, it is still not yet CE market which is necessary for it to be used legally. The purpose of this thesis is to investigate how the lifting beam complies with the existing directives, laws, and standards and provide a basis for CE marking. A six-step method for CE marking was decided as useful to fulfil the aims of this thesis. This method includes everything from identifying applicable directives and standards, relevant tests, documentation and a procedure to CE mark the product.The results show that the lifting beam shall indeed be regarded as a machine by the definition provided in the Machine directive 2006/42/EG and should therefore follow its requirements as well as the Swedish version of the Machine directive, AFS 2008:3. To verify which paragraphs of AFS 2008:3 the lifting beam complies with, does not comply with or are not relevant a risk analysis was performed. In order to interpret the meaning of the paragraphs in AFS 2008:3 and its appliance, a relevant standard for lifting beam was chosen which in this case was SS-EN 13155+A2:2009. The results of the risk analysis show that the lifting beam lacks in two areas, the technical documentation which needs to be completed and further tests of the mechanical constriction are needed for the lifting beam to finally be CE marked.

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  • 37.
    Höök, Therese
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Implementeringsplan för ett flexibelt produktionssystem vid Boggs Mekaniska AB2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med examensarbetet är att undersöka det nuvarande produktionssytemet och identifiera förbättringsförslag som skapar utrymme för en mer effektiv och flexibel produktion, och sammanfatta dessa i en implementeringsplan. En ökad flexibilitet i produktionen anses nödvändig för att i framtiden kunna möta efterfrågan som i framtiden kommer att ställa krav på snabbare leveranser.

    Vid kartläggning av nuvarande system framgår det att den genomsnittliga omställningstiden är lång inom produktionssystemet, vilket skapar problem då det råder stor artikelvariation hos Boggs Mekaniska AB. I och med de långa ställtiderna körs i dagsläget stora partier där seriestorlekarna varierar mellan 50 och 10000 stycken detaljer. Mycket utav den tillgängliga produktionstiden läggs i dagsläget på onödiga och icke värdeskapande aktiviteter som bedöms bero på en ostrukturerad arbetssituation för produktionspersonalen. Det råder även långa omställningstider vid flertalet maskiner. Produktionen är i stor utsträckning personalbunden och helt beroende av rätt operatör på rätt plats. Produktionsplaneringen upplevs bristfällig, främst beroende på otillräcklig kunskap i affärssystemet monitor, men även på grund av att omplaneringar och ändrade körordningar ställer till det i produktionen.

    För att hitta rätt lösning för produktionssystemet genomfördes en omfattande datainsamling i form av observationer, enkät, intervjuer, fokusgrupp, litteraturstudier, tidsstudier. Vidare kombinerades flertalet välkända förbättringsverktyg och metoder för att säkerhetsställa att rätt lösningar tillämpas utifrån den givna situationen. Några av de viktigaste analys- och förbättringsverktyg under arbetet gång har varit SMED analys och 5S och JIT.

    Arbetet resulterade i en implementeringsplan för hur arbete med 5S, smedanalys, och en ny layout bör se ut för att möjliggöra mindre partistorlekar, fler omställningar och ett ökat antal färdigställda ordrar på kortare tid, och på så vis göra produktionen mer flexibel. Vidare arbete bör genomföras främst enligt de steg som presenteras i JIT-modellen men även vad gäller produktionsplaneringen då den i dagsläget upplevs som bristfällande. Arbete med produktionsplaneringen anses ha betydande förbättringspotential gällande reducering av genomloppstiden.

  • 38.
    Iliev, Dimitar
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Discrepancies in solar irradiation data for Stockholm and Athens2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    The aim of this study is to evaluate the variation of solar radiation data between different data sources that will be free and available at the Solar Energy Research Center (SERC). The comparison between data sources will be carried out for two locations: Stockholm, Sweden and Athens, Greece. For the desired locations, data is gathered for different tilt angles: 0°, 30°, 45°, 60° facing south. The full dataset is available in two excel files: “Stockholm annual irradiation” and “Athens annual irradiation”. The World Radiation Data Center (WRDC) is defined as a reference for the comparison with other dtaasets, because it has the highest time span recorded for Stockholm (1964–2010) and Athens (1964–1986), in form of average monthly irradiation, expressed in kWh/m2. The indicator defined for the data comparison is the estimated standard deviation. The mean biased error (MBE) and the root mean square error (RMSE) were also used as statistical indicators for the horizontal solar irradiation data. The variation in solar irradiation data is categorized in two categories: natural or inter-annual variability, due to different data sources and lastly due to different calculation models. The inter-annual variation for Stockholm is 140.4kWh/m2 or 14.4% and 124.3kWh/m2 or 8.0% for Athens. The estimated deviation for horizontal solar irradiation is 3.7% for Stockholm and 4.4% Athens. This estimated deviation is respectively equal to 4.5% and 3.6% for Stockholm and Athens at 30° tilt, 5.2% and 4.5% at 45° tilt, 5.9% and 7.0% at 60°. NASA’s SSE, SAM and RETScreen (respectively Satel-light) exhibited the highest deviation from WRDC’s data for Stockholm (respectively Athens). The essential source for variation is notably the difference in horizontal solar irradiation. The variation increases by 1-2% per degree of tilt, using different calculation models, as used in PVSYST and Meteonorm. The location and altitude of the data source did not directly influence the variation with the WRDC data. Further examination is suggested in order to improve the methodology of selecting the location; Examining the functional dependence of ground reflected radiation with ambient temperature; variation of ambient temperature and its impact on different solar energy systems; Im pact of variation in solar irradiation and ambient temperature on system output.

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  • 39.
    Jansson, Anneli
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Kapacitetsförbättring med effektivare materialhantering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To cope with anticipated future increase in production LogMax should improve material handling around the assembly. The questions that the study will answer are: How can LogMax streamline the assembly to meet the production increase? What methods can be easily implemented to improve materials handling? Capacity enhancement means to shorten assembly times for each unit, which can be done in several ways. The report provides three suggestions on how LogMax can place assembly lines (work – cells), roller conveyors for pallets of materials for the assemblers and where pre – assembly can be done. Even their advantages – and disadvantages are described. Methods for improvement are to: (1) introduce of Lean Manufacturing, which reduces, inter alia, time – wasting engines to retrieve details of the inventory, (2) introduction of 5 S in tool cabinets, and (3) introducing Kanban – board, which serves to check and balance the assembly lines. For further assistance with balancing are proposed that LogMax can balance assembly lines using group of mounting. Calculations show that LogMax need to have at least 14 manned workstations per day to achieve the headline goal 2017.

  • 40.
    Johansson, Linnéa
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Electrical coupler cover: Evaluation from a material-technical perspective2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the electrical coupler cover is to protect the electrical contacts underneath. The electrical coupler cover is today made of a metallic material that conducts electricity. In the event of a collision, the electrical coupler cover can be deformed. This creates physical contact with the pins and short-circuit the current, which can lead to several problems. The task will be to look at if there are non-metallic materials that do not conduct electricity and meet the requirements that are set for the cover. Composites are the materials which are evaluated, and the results is that glass fibre reinforced polymer is the most suitable material. Since the structure of the polymer and the fibres orientation has a major influence on the material properties it is possible to tailor the composite for specific properties. Polymers generally have low electrical conductivity which is important for the application. With the help of a computer program and the set requirements, some possible composites were found and then compared with each other. When the materials were compared to each other it was found that the design for the cover will need to change if a composite is used. The wall thickness of the cover must be increased or otherwise strengthen compared to the metallic version.

  • 41.
    Johansson, Roger
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering. KTH, Industriell produktion.
    Implementation of Flexible Automatic Assembly in Small Companies: Flexibility and Process demands2002Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis has its focus within Flexible Automatic Assembly (FAA) systems and its implementation in small companies. The small companies are an important part of a country’s industry and economy. The need for the small company to increase the technology level, in order to be competitive in a global market as a supplier, is evident. The prevailing competence and economical resources of most small companies are often limited, a fact which underlines the need for economical, technological and application flexibility for their assembly system solutions. Therefore, these needs could be viewed as the main objectives posed on solutions which claim to be flexible, such as FAA systems.

    The objectives for this thesis are:

    - to investigate the state-of-the-art in FAA systems; the primary focus of the investigation residing upon flexibility issues. Theoretical study.

    - to investigate the implementation process in a small company that tries to apply FAA technology, and observe the problems that must be solved. Empirical study.

    - propose an approach as to how FAA systems should be structured.

    As a prerequisite for the proposed structure, the state of the art within FAA systems is discussed with focus on flexibility. The work in this thesis is based on the hypothesis that if systems are developed with properties satisfying the SME needs, the FAA-systems would be user-friendlier both in an economical- and a competence perspective. Hence the need to evaluate the status of current FAA systems.

    The work attempts to illustrate, through the theoretical and empirical studies, that there are three main factors that limit success when implementing FAA systems in small companies: Competence acquisition, Product design and Strategy for implementation. Learning, or competence acquisition, is most often carried out in parallel with the actual use of the system. This extensive learning phase most often leads to the system becoming obsolete during its expected run-time (period of use). The product design is another area of interest as it often seems hard to motivate product changes to facilitate automatic assembly, especially if no system is at hand as a driving force. The work also showed that there is a lack of strategy for implementation of FAA. The understanding of the FAA system impact on the product development and manufacturing is not understood, thus, the implementation is treated as a local phenomenon in the assembly shop. Furthermore, the ii uncertainty concerning future development of products is reflected in short payoff times, which makes the economical justification of systems difficult.

    All of these factors have been misrepresented to date due to a loose application of the term flexibility, and its implications. Therefore, the work attempts to clarify the flexibility issues, in terms of the assembly process demands, and also proposes a new flexibility map.

    To facilitate implementation of FAA into small companies, a modular assembly system approach is proposed. The modules should be task oriented. By using a modular approach, the possibility to have a system that is easy to keep up to date with product development, is greatly improved and the risk to invest in dead ends will decrease. Furthermore, it should become simpler to find an optimal level of automation or to prioritise the flexibility efforts, and thereby reduce the cost for maintaining flexibility over the system lifespan.

    A way to develop a decision.making tool for prioritising the flexibility efforts is proposed by using a Penalty-of-Change curve, which exploits the proposed flexibility map as a base. The modular approach is a way to decrease the negative correlation between dynamic flexibility (on-line) and static flexibility (off-line), since too much dynamic flexibility otherwise tends to limit the possibility to change the system to new situations. The modular approach isolates this negative correlation within modules. The technological adaptability will increase if a modular system is used since the standardised interfaces between modules define clear borders between functions or tasks within a system. Furthermore, a modular approach facilitates stepwise knowledge acquisition since it will be natural to focus on modules instead of entire systems.

    A leading idea in this thesis is, that small and large companies have the same system demands at module level, which makes it possible to increase the market for standardised modules and thereby decrease the cost for such modules. In other words, standardised modules, instead of systems. Modular systems are not optimised in terms of a low cost/capacity ratio for a certain product generation, instead, the system is optimised towards, reconfigurability to be able to follow product evolution, or totally rebuild for new products. Which, in the long run, may lead to a low cost/capacity ratio. Therefore, a prerequisite for the use of modular systems is that the systems will operate in a frequently changing market where fast ramp-up are more important (to maintain the market share) than an optimised system for each product generation.

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  • 42.
    Johansson, Roger
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Understanding the product: Backtracking the QFD connections via the product structure2020In: DS 101: Proceedings of NordDesign 2020, Lyngby, Denmark, 12th - 14th August 2020: Balancing Innovation and operation / [ed] Mortensen, N.H.; Hansen, C.T. and Deininger, M., The Design Society, 2020Conference paper (Refereed)
    Abstract [en]

    The subjectivity involved when creating a Quality Function Deployment (QFD) and the need for companies to understand how their product is fulfilling the customer needs are the focus of this paper. Literature is pointing out the subjectivity when using QFD. Therefore, a method was developed and explored with the aim to try to backtrack and verify the QFD connections via the product structure and thereby reduce the uncertainty. The method calculates a connection strength value for the QFD by summoning connection strength values for three matrices: customer requirements to functions, the functions to technical solutions and technical solutions to product properties. The model was implemented in a relation database and tested using a simple product. The test shows some promising results but also shows sources to uncertainty. Some identified reason for uncertainty were for instance unbalanced matrices, difficult estimates of ratios and redundancy in matrices. The test shows that by working with the model and try to understand why the model gives different results than the QFD gives a better understanding of the product.

  • 43.
    Johansson, Roger
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Erixon, Gunnar
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering. Royal Institute of Technology.
    Assessing Flexibility: The Frequency and Horizon Approach2001Conference paper (Other academic)
    Abstract [en]

    This paper focuses on flexibility in the area of flexible automatic assembly systems. Far-reaching research has been done in effort to develop flexible automatic assembly systems. A dilemma that appears in understanding the focus for these research projects is the immense amounts of flexibility concepts used. This paper proposes a structure for the concepts based on frequency and horizon for different events in an assembly system. The results are presented in a proposed “flexibility map”. Based on the “frequency and horizon approach” and the definition of flexibility as “the penalty of change” [1], an argumentation concerning what kind of flexibility is most valuable in an assembly system can be discussed. The paper also points out the demands for a flexibility that allows for de-coupling of high and low frequency events in a system. A clear distinction is made between dynamic flexibility and static flexibility. It is a well-known fact that the increase of the dynamic flexibility in an assembly system will decrease the static flexibility [2]. The paper ends with a proposal for decreasing the negative correlation between dynamic- and static flexibility. An objective for further research concerning whether a certain process within an assembly system affects certain flexibility is also presented.

  • 44.
    Johansson, Roger
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Erixon, Gunnar
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering. Royal Institute of Technology , Sweden.
    Modular FAA-SYSTEMS: A way to facilitate justification and implementation of FAA into small and middle sized companies2002Conference paper (Other academic)
    Abstract [en]

    Small companies are the backbone of any nations industry and they are often sub contractors to major corporations, which set higher and higher demands on them. In order to survive they will inevitably be obliged to comply with the requirements [Onori et al., 2000]. In order to do so, one step is to increase their technology level. Therefore, this paper focuses on modular FAA in order to facilitate the implementation of FAA-systems into small companies. How well companies succeed in the implementation of a new technology in manufacturing depends largely on how well they understand the dependency between products and processes. Is it the right technology for the companies manufacturing system? What has to be done to the products in order to use this technology? A paradox is that new technology in manufacturing can often be justified only when a new product launch is planned. This is probably true also in the case of Flexible Automatic Assembly Systems (FAA) where the possibilities to introduce a well functioning system to use with existing products are very limited.

  • 45.
    Kalrot, Mikael
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Studie om hydraulmedietsinverkan på prestanda vid gnistbearbetning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    EDM is a method that is frequently used in service of nuclear power plants. The method

    is preferred because it causes minimal thermal and force impact on the detail, making it

    suitable to use where resistance to fatigue is of importance. The processing method is

    well proven, but the control of the tool is done via an ungainly hose/cable package

    which is not optimal. One possible step on the way to improving the method is to

    replace the hydraulic fluid, which today consists of de-ionized water and UltraSafe

    glycol mixture, to only consist of de-ionized water. With this new hydraulic fluid, the

    hydraulic part of the hose/cable package could be eliminated (or at least reduced) as

    the pump that supplies the hydraulic pressure to the tool can be moved to the tool. This

    study shows that there are no apparent problems for such development. Material

    removal rate, surface roughness and ease of use, using water as hydraulic fluid are

    comparable with UltraSafe, though other obvious advantages are present, particularly

    such as the environment areas and the workplace environment.

    The report has been commissioned by Westinghouse Electric Sweden AB in Västerås,

    Sweden and will be presented to the commissioner.

  • 46.
    Kalrot, Theres
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Produktutveckling av gripfingrar: för ökad användarvänlighet vid produktionsomställningar2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The degree project has been conducted at Högskolan Dalarna in cooperation with Mora Automation and Robotics AB in Orsa and deals with product development of gripping components for robotic management. The work concerns their range of gripping components, and the goal has been to develop a concept proposal that enhances and simplifies the conversion process with today's gripping segments. Shorter product life expectancy and greater variability spread increasingly demand for flexibility in manufacturing processes. This leads to more frequent changes in production equipment and also the robots found in the production. Adaptation of the robot and its equipment to changes in production must be possible in a simple and reliable way, and the purpose of the report is therefore to investigate the difficulties encountered in the conversion of the robot's gripping device and to propose design changes that could prevent them. Through interviews and observations of the product in use, problem areas in the conversion process have been identified. The biggest challenge can be found in achieving a correct and symmetrical positioning of the gripper fingers on the base jaws. A simple dimensionless grading on the jaws and gripping fingers can provide better adjustment options and lead to significant improvements without the development project being too resource-intensive.

  • 47.
    Karlsten, Robin
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Fastställning av orsak till prematurt brott i upphängningskomponenter: En studie för att fastställa orsak till brott i bladfjädrar2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A failure analysis was carried out to determine the characteristics of fractures in two supplied leaf springs which had fractured long before their expected life cycle had come to an end. These fractures were analysed in a scanning electron microscope to determine these characteristics and narrow down the possible causes of these fractures. A conclusion from this analysis could be made that some sort of embrittlement had occurred which caused the fracture to propagate in the grain boundaries of the material, a phenomenon which normally occurs below the material’s transition temperature where lower temperatures causes the material to become brittle. Further tests were carried out to determine the material’s impact energy absorption and to compare it to the specified values. This also provided simulated fracture surfaces which could be compared to the supplied ones which had occurred during use. In the same way, fracture surfaces were simulated from a healthy material which did not show signs of this embrittlement. Studies implied that the grain boundary embrittlement occurs somewhere in the manufacturing process on a small percentage of the manufactured leaf springs. The study became focused on locating the processes which could cause this phenomenon. Test results, microscope analysis and litterature studies all seem to point to a phenomenon called temper embrittlement. This phenomenon can occur in materials where there is a presence of impurities included in the material. These impurities can then react with substances in the material during holding in a temperature interval in the tempering process. This phenomenon can be countered by either reheating the material or by acquiring a purer material with less inclusions of impuring substances.

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  • 48.
    Kenger, Patrick
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    The way we design: a design process and manual for industrial product development2018In: Proceedings of NordDesign: Design in the Era of Digitalization, NordDesign 20182018, Linköping: The Design Society, 2018Conference paper (Refereed)
    Abstract [en]

    The design work made by designing engineers need to be clearly defined and structured. The design process to follow should naturally lead to a systematic design work that reduce wasteful work, and reuses competence and knowledge from previous design work. The design process should lead to a design work that is made with as little lead-time and cost as possible, yet with a resulting part or product with the right quality. In a time when products become more complex regarding performance, tolerances, material, and with more technological and digital things built into the products, this design process becomes even more important. The Way We Design (TWWD) presented in this paper is one contribution to such a design process for the day-to-day design work. The work behind TWWD is based on both research and industrial practice. The process is built on 11 (A to K) number of checkpoints which gives details on the design work and is customised for the specific company.

     

    Included in TWWD, as addition to the design work itself, are details regarding documentation and templates, standards, and directives. TWWD also include details of the design requirements from other departments within the company, such as sales, purchasing, assembly, manufacturing, painting and service. In this way, the designers can incorporate the requirements from their internal colleges and reduce much of the rework due to misinterpretations or design errors that are detected downstream in the manufacturing process or even at the customers. The TWWD process has been implemented at some companies as their manual for how to perform the design work. The results indicates that it is possible to reduce the design lead-time ranging from 5% to 20%, and with better precision in doing the right things and to reduce wasteful work. The design engineers at a medium and at a large company says that it is the resulting design quality that is the most beneficial from TWWD.

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  • 49.
    Kenger, Patrick
    et al.
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Erixon, Gunnar
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Studies of Design and Assembly Defects on Integrated and Modular Architectures2005In: 15th International Conference on Engineering Design, ICED 05, Melbourne: International Conference on Engineering Design (ICED) , 2005Conference paper (Refereed)
    Abstract [en]

    It is known that despite companies’ efforts to improve the quality of their products, design and assembly defects results in large repair costs both in terms of repair and providing feedback to the origin of the defect. The purpose of this paper is to study these types of defects and the defect rates in design and assembly. The paper presents a web based questionnaire answered by 29 companies. The result shows that the defect rate (defects per product) spanned from 0.01 to 10. Also, design and assembly defects covered 46%, 23% respectively, of all occurred defects. A case study is also presented, performed at a company who recently implemented a modular architecture. In this company, defects from 5 700 integrated product architectures are compared with defects from 431 modular architectures. The average defect rate increased by 21.5% – from 0.65 to 0.79 – when a more modular architecture has been implemented. Furthermore, the study showed that the assembly defects have decreased while the design defects increased. The results presented in this paper will also support the development of the MPV (Module Property Verification) method which is briefly described.

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  • 50.
    Kenger, Patrik
    Dalarna University, School of Technology and Business Studies, Mechanical Engineering.
    Beneftis of modularity and module level tests2005In: Emerging solutions for future manufacturing systems, International Federation for Information Processing., 2005, Vol. 159, p. 379-386Conference paper (Refereed)
    Abstract [en]

    Many companies implement a modular architecture to support the need to create more variants with less effort. Although the modular architecture has many benefits, the tests to detect any defects become a major challenge. However, a modular architecture with defined functional elements seems beneficial to test at module level, so called MPV (Module Property Verification). This paper presents studies from 29 companies with the purpose of showing trends in the occurrence of defects and how these can support the MPV.

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