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  • 251.
    Larsson, Kristoffer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Jämförande studie av tillverkningsmetod vid cisternbyggnationer2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is a comparative study of the manufacturing method of tank constructions that has been carried out in the spring of 2016. The work has been performed together with the Tank department at Rodoverken AB. Rodoverken builds accumulators, cisterns and pressure vessels with a unique construction method called The spiral method. The aim of the work was to evaluate proposed plate sizes used in the spiral method. The evaluation will focus on the time and cost savings the company can make with the use of different plate sizes.

    The procedure during the work started with studying the theory and the methods that were relevant to the topic. This theory chapter contained both information about the company's building technology and models used in this study to meet its primary goal. In the next step the data collection started, the aim was to gather information and identify which aspects were affected by the extended plate sizes. The data collection was conducted through studies on previous work, observations and interviews. When all the data were collected the analysis work started. An aspect impact study was performed together with the company. The impact study contained all the identified aspects and their consequences. After this an FMEA-analysis was performed based on the previous aspects, this showed the most critical aspects based on the availability, seriousness and the possibility to affect the problem.

    The calculations on this study were carried out on proposed plate sizes that Rodoverken had contributed. An evaluation was made with three different plate designs to calculate the time and cost reduction based on the total meter weld on the tank. The old plate design was used as a reference and two new larger plate sizes were used in the evaluation as well. A summary was made containing the costs that increases when the company starts to use larger plate sizes. This included the cost of transport and the necessary equipment that has to be invested in order to handle larger sheet sizes. The compilation of cost including the cost reduction in welding and the costs of transport and new investments were compiled and provided the total savings of the different plate sizes.

    The total savings of the different plate sizes:

    Plate size 2 (3300x9600mm): 127155 kr.

    Plate size 3 (3200x10700mm): 146800 kr.

  • 252.
    Lehtinen, Jesper
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Myrén, Jennie
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Framgångsfaktorer för effektivare förbättringsarbete2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis was originated by Volvo Penta in Vara announcing a need to shift the focus and streamline the company's efforts for improvement. Previously, the focus had been directed towards the workplace standard and 5S, but now the focus will be on minimizing waste and reducing causes of quality defects and delayed deliveries. The project group was given the perspectives of organizational culture, work structure and leadership philosophy by Varafabriken as a starting point for creating a proposal for change. Along with this proposal for change, the project was asked to provide suggestions for how Varafabriken can achieve a higher efficiency in a customer-focused improvement process after reorganising into teams as well as looking at how management can be structured to make the improvement process in a manufacturing industry more effective. Answering these questions became the main goals for the project.

    Methods used to achieve these goals are literature studies, interviews, surveys, observations and benchmarking. The literature studies provided a picture of how different authors advocate that organizations should be managed to achieve higher efficiency. The 16 interviews revealed that targets in Varafabriken inhibits the improvement work and that the maintenance department that executes improvements does not have sufficient resources. The survey, with 49 respondents, strengthened the answers from the interviews indicated that the target figure related to the number of deviations per week inhibit the improvement work. During benchmarking the authors noted that the majority of the visited companies preferred to neither measure the number of deviations nor the number of improvements per employee and year. It could also be seen that three of the four companies saw a success factor from paying attention to and developing the organization’s personnel.

    Finally, the three perspectives that the thesis was given increased to four; man is the new perspective because the individual is deemed important by the authors. Based on the collected data, a proposal for change was created for Varafabriken. The change proposal is that the Varafabriken should implement Toyota Kata to obtain an increased focus on the factory’s personnel and work more proactively with improvements. Toyota Kata implements a coaching leadership that develops individuals and creates routines and behaviors that lead to a sustained pattern of thinking around improvements. The authors also recommend Varafabriken to liquidate target figures concerning the number of deviations and the number of improvements per employee and year. In addition, focus should be aimed towards the maintenance department as they are essential for the effectiveness of the improvement work.

  • 253.
    Lennartsson, Edvin
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Thorleifsdottir, Birgitta
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Steglöst växelsystem för cykel2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project tackles the idea of developing a continuous variable transmission (CVT) for bicycles in order to make shifting gears while riding uphill easier. This problem was chosen in hopes of making a difference in the world of cycling for commuters and leisure cyclists, as well as contributing to the environment and society's health and wellbeing. The goal was to design a seamless transmission, where one could choose from an infinite amount of gears on a given interval. Originally, the possibility of shifting gears while stationary was considered a desirable addition, as well as the possibility of an automatic transmission, although neither of these ideas were included in the final concept.

    The project primarily focused on product development, where benchmarking played a large role, especially when it came to gathering knowledge and information on existing CVT's from all markets. The reason for this was that existing commercially successful CVT's within the bicycle market were rather scarce, thus the need for ideas from other markets. Out of all existing CVT's, four types were considered likely to be possibly implemented as bicycle gears. Out of these four, one type surpassed the others during selection: the Variable Diameter Pulley (VDP).

    The question as to how a VDP would be designed, in order to implement and mount it on a bicycle, was answered trough many hours of idea generating and concept selections, until the final concept was left standing. The final concept is a spring and hydraulic controlled VDP transmission, which is regulated through a hand driven pump and has an infinite number of gear ratios within a 240% range.

    The main principle of the concept works, although it is noteworthy that due to large axial forces the springs in the design are far too large for the design to be successfully mounted on a bicycle. Furthermore, the range of the gear ratios can be considered quite small. The conclusion is that the idea is functional, however in order for it to become a successful CVT for a bicycle it requires further work, particularly in regards to finding replacements for the springs.

  • 254.
    Leon Zapata, Diana
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Gapanalys av Bror Tonsjö ABs ledningssystem mot ISO 9001:2015 och 14001:20152016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to investigate the procedures that need to be changed or introduced in the company Bror Tonsjö AB’s existing management system in order for them to be certified in ISO 9001:2015 and ISO 14001:2015. The objective is also to make suggestions on procedures that can be integrated to the company to implement an integrated management system.

    In order to achieve the objectives a Gap Analysis was performed to get an overview of Bror Tonsjös current situation. The input for the Gap Analysis consisted of a comparison between the standards ISO 9001:2015 respectively ISO 14001:2015 against ISO 9001:2015 respectively ISO 14001:2004. The compared requirements were then checked against Bror Tonsjö’s management system. The Gap Analysis resulted in identification of the extent of the gaps in the company’s management system.

    The largest and most critical gap involved the organizations preconditions which included that Bror Tonsjö in the current situation doesn’t have a detailed documentation regarding the extent and requirements needed to meet the requirements of ISO 9001:2015 and ISO 14001:2015. The new editions of ISO 9001 and ISO 14001 also directs focus on risk-based thinking and consideration of the risks and opportunities in the design of management systems. The result is that the company also received a large gap regarding the risk-based thinking and the risks and opportunities in the planning of the management systems.

    The presented solutions should close all the identified gaps. As regards to the gap regarding the organizations preconditions, a material is presented that contains among other things questions for an stakeholder analysis and questions about what the company offers. The material covers the requirements of both ISO 9001:2015 and ISO 14001:2015. To close the gap concerning risks Tonsjö should for example consider the implications a change could bring or if the function is preserved after the changes are made.

    Based on the presented solutions, it has also appeared that the routines from the quality and environmental management systems could be integrated into one management system. Both ISO 9001:2015 and ISO 14001:2015 are constructed in the same way. Because of the similar structure Tonsjö should be able to integrate their management systems without any major problems. To enable the integration of the management systems, Tonsjös management must be engaged and take responsibility for the management systems during the integration. It’s also important that the management engages the personnel that is affected by the integration of the management system to achieve a good result.

  • 255.
    Li, Peigang
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Cold lap formation in Gas Metal Arc Welding of steel: An experimental study of micro-lack of fusion defects2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cold laps are defined as micro-lack of fusion defects at the weld toe more or less parallel to the surface of the parent plate. These defects are known to negatively influence the fatigue properties of weldments. Previous studies suggest that cold lap formation can not be avoided completely in Gas Metal Arc Welding (GMAW). Therefore, a better understanding of formation mechanisms is imperative to be able to minimize the number and size of these defects. The main objective of this work has been to provide a more comprehensive understanding of cold laps, including categorising, characterisation and defining the most significant factors for formation. GMAW was used to produce welds that were investigated by metallographic methods using light optical microscopy, scanning electron microscopy and energy dispersive spectrometry. A novel classification of cold laps was introduced and three types of cold laps were identified: spatter cold laps, overlap cold laps and spatter-overlap cold laps. It was shown that cold laps are partially or fully filled by oxides. The most common oxides are manganese silicon oxides which were concluded to be formed primarily by oxidation of droplets. The presence of oxides was found to significantly increase the tendency to form spatter cold laps as well as overlap cold laps. Particularly for overlap cold laps, it was found that the depth (in transverse direction of weld) is reduced when welding in a non-oxidising environment. Welding on blasted surfaces increased the cold lap formation by entrapment of gas. The droplet and base metal temperatures were also found to be significant factors in cold lap formation. For overlap cold laps the occurrence frequency decreased with increased preheating temperature of the base metal. Mechanisms of overflowing resulting in overlap cold laps were discussed based on an extensive literature review. Several phenomena are believed to contribute to overflow including Rayleigh instability, the balance of forces, transfer of lateral momentum by droplets and an outward Marangoni fluid flow of the weld pool.

    The present studies suggest that cold lap formation can be suppressed by ensuring that the welding process (arc) is as stable as possible and by welding on a preheated work piece in a non-oxidising environment.

  • 256.
    Li, Peigang
    et al.
    ESAB AB, Gothenburg, Sweden.
    Hurtig, Kjell
    University West, Department of Engineering Science, Division of Welding Technology.
    Högström, Mats
    University West, Department of Engineering Science, Division of Welding Technology.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Welding Technology.
    Scotti, Americo
    University West, Department of Engineering Science, Division of Welding Technology.
    A contribution to the study of negative polarity in GMA welding2018In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 95, no 5-8, p. 2543-2553Article in journal (Refereed)
    Abstract [en]

    GMAW using the electrode with negative polarity (DCEN) has been frequently suggested as a potential means of increasing production capacity. The objective of this work was to further study the performance of negative polarity in GMAW of carbon steels. In this project phase, bead-on-plate welds were carried out in flat position to assess the effect of different potential shielding gas compositions on bead geometry, finishing and spattering. The characteristics were compared with DCEP at the same current, but depositing the same volume of material per unit of length (more industrial related comparison). The arc length was kept the same by adjusting voltage to reach shortest arcs, yet with suitable non short-circuiting metal transfer mode. An approach to measure bead convexity was also proposed and assessed. The results showed that DCEN is feasible as a means of increasing GMAW production capacity. However, to become DCEN applicable with GMAW, the results suggest an Ar based blend with around 6.5 % of O2 is the most appropriate shielding gas, as much as that there is a demand for a standard electronic controlled power source able to work in constant current mode. 

  • 257.
    Li, Peigang
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Markocsan, Nicolaie
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Karlsson, Leif
    University West, Department of Engineering Science.
    Cold laps - micro-lack of fusion defects in steel arc welds: a reviewManuscript (preprint) (Other academic)
  • 258.
    Lindgren, Lars-Erik
    et al.
    Luleå Technology University.
    Babu, Bijish
    Luleå Technology University.
    Charles, Corinne
    University West, Department of Engineering Science, Division of Production Engineering.
    Wedberg, Dan
    Luleå Technology University.
    Simulation of manufacturing chains and use of coupled microstructure and constitutive models2010In: Finite Plasticity and Visco-plasticity of Conventional and Emerging Materials / [ed] Aktar S Khan, Babak Farrokh,, Fulton, Maryland, USA,: NEAT PRESS , 2010, p. 4 s.-Conference paper (Refereed)
  • 259.
    Lindqvist, Björn
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Johansson, Victor
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Layout av arbetsstation vid nyproduktionslina: ett konceptförslag till IAC Group AB2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is performed at International Automotive Components (IAC) Group located in Färgelanda, Sweden. The purpose of the work is to propose a layout of a workstation in a new production line that will be launched in autumn 2017. A layout means physical location of the components in the station. The parts produced by this production line are details of a roof shelf which is part of the interior of a Swedish leading truck manufacturer. During the project, the production line is currently being assembled and some test series is run.The work station that this thesis deals with is a welding operation of the lids before transported to a final assembly. Because the lids are manufactured in different models, the weld needs replacement of tools in order to process the current part. Different assembly tables also needs to be replaced depending on the model of the lid witch is to be manufactured.

    The work station needs to effectively have a flow of material, while the operators must have an ergonomically designed workplace, and that requires a carefully thought out layout. The process of preparation of this layout was done with methods of product development where concepts are generated and evaluated. The concept development process has been in consultation with the company supervisor and production. A total of six concepts were generated and they were graded and weighted in a matrix, which later led to the choosing of a basic model. After selecting the basic model were more concepts generated in a more detailed cell design. The last generated concepts were presented to the staff involved that eventually opted for a final concept when it met the requirements and preferences that were set. Part of the thesis was also to simulate the work of the operators, ensure the balancing and suggest possible improvements. The results in the report describes the final concept together with recommendations and guidelines of lean production.The actual implementation of the layout will be done by the company themselves.

  • 260.
    Lindqvist, Hugo
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kristiansson, Robin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Viktoptimering av maskinrummet på lastfartyg: En studie i topologioptimering för dagens sjöfart2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this bachelor thesis was twofold. First, to investigate whether or not the engine room in cargo ships constructed by Fartygskonstruktioner AB contained dimensions that exceed relevant acquis. Secondly, to give a proposal on how topology optimization could be used to reduce the overall weight of the engine room.

    In order to identify the dimensions of the structure in the engine room a review of drawings was conducted of two different cargo ships constructed by Fartygskonstruktioner AB. These dimensions were compared to acquis from Det Norske Veritas Germanischer Lloyd and Bureau Veritas as well as recommendations from the engine manufacturer. The review confirmed that the floors were oversized. Therefore, the thesis focused on reducing the weight of the floor and the surrounding structure.

    A three-dimensional model of the structure was created in order to make optimization and numerical calculations possible. A finite element analysis was conducted in order to investigate the maximum equivalent stresses. The stresses for the structure in the engine room before topology optimization were calculated to 6 MPa in contrast to 282 MPa which according to Det Norske Veritas Germanischer Lloydand were the lowest allowed maximum equivalent stress.

    The result of the topology optimization showed how the formulation of the floors, engine foundation and the structure below the main engine could be modified in order to reduce the weight of the engine room. The floors were replaced by structure closely resembling props. The engine foundation was altered in such a way that the transverse structure was partly eliminated and the structure between the main engine and the gear including the clutch was removed. The holes that were placed in the structure below the engine foundation attained an increased circumference. The weight of the structure was therefore reduced by 38 % which corresponded to 19 ton.

  • 261.
    Lingbrand, Johan
    University West, Department of Engineering Science.
    Analys och beräkning av konsignationsmaterial i pall hos Parker Hannifin AB i Trollhättan2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Parker Hannifin AB i Trollhättan ingår i en koncern som består av 263 fabriker med över 50 000 anställda. Med 300 anställda produceras, utvecklas och säljs huvudkomponenterna i mobila hydraulsystem. Parker i Trollhättan har konstruerat och tillverkat fasta pumpar och motorer för lastvagnar sedan 1980-talet.

    Genom att eliminera aktiviteter som inte är värdeskapande och införa nya system strävar Parker efter att uppnå kortare ledtider, minskat bundet kapitel och ständiga förbättringar. Orsaken till att Parker vill införa konsignation är att det innebär många fördelar. Fördelarna är bland annat minskad administration, minskat bundet kapital och ökad tillgänglighet av detaljer.

    Examensarbetet visar att den största vinsten med konsignationslager för kunden är att det eliminerar flera delar av flödet mellan avtal till betalning. Delar som elimineras är avropsarbete, fysisk mottagning, mottagningsrapport, lagerbokföring, fakturaregistrering, fakturakontroll samt materialrekvisition. För leverantören är vinsten att fritt kunna planera försörjningen till kunden efter sin egen kapacitet. Samtidigt lagras materialet kostnadsfritt hos kunden, Parker i Trollhättan.

    Detaljerna ägs av leverantören då de ligger på lager hos Parker. Resultatet av examensarbetet visar att ägandet av material bör övergå till Parker då arbetsordern avrapporteras. Detaljernas lastbärare består av hel-pallar, där pallarna märks upp av en pallflagga. I examensarbetet har en pallflagga för konsignation skapats. Pallflaggan upplyser om att pallen innehåller konsignationsmaterial som ägs av leverantören. Informationsflödet är tydligt eftersom en fraktsedel skickas med det skickade materialet till Parker. Fraktsedeln kontrolleras med följesedel som fås av leverantören. Information måste också ges ut vid större förändringar i förbrukning så att båda parter känner sig trygga över vad som lagerhålls. Konsignation bygger på ett långsiktigt samarbete och bidrar till en tätare relation mellan företagen. Konsignation innebär en vinna/vinna-situation.

  • 262.
    Liu, Yuan
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Effect of CNC axis movement on the surface roughness in milling2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this paper, the performance of a new measurement system CITE (CNC Integrity Tracing Equipment) is investigated. CITE measurement system is the name given to the data acquisition hardware and software developed by University West for recording the movements of CNC machine tools. It can be used for monitoring of the milling process and recording the milling errors. The aim of this study is investigate the capability of the CITE system in prediction of the surface roughness. In an example cutting test, the CITE measurement system was used for recording selected sections in straight milling process and curved milling process. After that, surface roughness, predicted by the CITE measurement system, was compared with the CMM (Coordinate measurement machine). The investigation shows that the CITE measurement system is comparable to the CMM for evaluation of roughness in curved sections. In straight sections, the evaluation of roughness by CMM machine is close to the simulation values that predicts surface roughness considering tool run-out.

  • 263.
    Lorentzon, John
    et al.
    University West, Department of Engineering Science.
    Järvstråt, Niklas
    University West, Department of Engineering Science, Division of Production Engineering.
    Modelling tool wear in cemented-carbide machining alloy 7182008In: International journal of machine tools & manufacture, ISSN 0890-6955, E-ISSN 1879-2170, Vol. 48, no 10, p. 1072-1080Article in journal (Refereed)
  • 264.
    Lugnberg, Mattias
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Netz, Tobias
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Investigation of thermal spring back of a hot formed 22MnB5 A-pillar with tailored properties2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a world where fuel economy and crash safety is becoming an important factor in the automotive industry, the need for materials with very high strength-to-weight ratio is growing rapidly. One of the materials used for this purpose is the boron steel 22MnB5. Since the material has very high mechanical yield limit it is hard to produce parts using cold forming, which is the standard procedure for sheet metal forming. Therefore, the use of hot stamping is increasing. Hot stamping enables manufacturing of boron steel parts with good dimensional accuracy and low spring back. However, some amount of spring back is still present during the process.

    In this thesis, spring back of a hot formed 22MnB5 A-pillar is investigated using computer simulations in the software LS-DYNA. The main focus was to develop a process for simulating spring back in hot stamping.

    The work started with simulations of the forming and quenching stages of the hot stamping process, both on a full size and on a smaller section of the blank. Simultaneously as the simulations, a literature study was also conducted. The literature study was aimed at finding hints and information on how to build the simulations. Furthermore, interviews were made with experts on both LS-DYNA and hot stamping.

    A process for spring back evaluation was then created and written as an LS-DYNA keywordfile.

    In the developed spring back simulation, the part is taken out of the press right after the quenching is finished and placed in a space where it can cool and move freely. The simulation is conducted until the part reaches room temperature.

    After the quenching is done, data containing temperatures, stresses and strains of the part is exported. This data is then included in the spring back simulation where the part is cooled to room temperature. During the cooling, the stresses, strains and temperatures are equalized until the spring back reaches a steady state.

    The results indicate that the developed method for spring back evaluation can be used to foresee shape deviations for the intended part and process.

  • 265.
    Lund, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utveckling av hydrauliktestutrustningskoncept för Rolls-Royce och Bentley2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This document is my bachelor’s thesis at The University West, Trollhättan, Sweden. The project is made as a part of a product development process in cooperation with Rohdins Automobile Service AB, Trollhättan, Sweden. The company’s speciality is service, repairs and renovations of Rolls-Royce and Bentley motor cars. Some of the most common cars in the workshop is Rolls-Royce Silver Shadow and Bentley T-series. These cars have a relatively advanced hydraulic height control system and the purpose is to keep the height of the car constant, independent of load conditions.

    Malfunction in the height control system is a fairly common problem and can result in reduced brake capacity. Present methods for fault diagnosis will often be time consuming and there is a demand for a more efficient way. Therefore, a concept for a hydraulic test equipment has been developed.

    The most important parts of the development process are research, identify needs, concept development and presentation. The concept will make it possible to test all height control components. The test equipment can also be connected to the car to test the complete height control system. The principal function builds on pressurizing hydraulic components to measure flow- and pressure characteristics. All components in the height control system has their own specific values of flow and pressure, which makes it possible to indicate the condition. The test equipment is electrically driven and is intended to be used in the workshop. It is possible to upgrade the product with a software based control system, so that automatic test programs can be used.

  • 266.
    Lundgren, Fredrik
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Montero Martinez, Salvador
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konceptutveckling av en hundsele som är säker för hunden och passagerare vid krock2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of the work presented in this report is to develop a concept of a dog harness that is safe for both the passenger and the dog during crashes and while traveling in vehicles. The reason for the concept development is that MIM Construction believes that the harnesses available on the market are not properly dimensioned for the forces that arise during collisions. The concept has been developed to simplify its use, make it intuitive and to minimize the risk of incorrect use. The harness design and quality must reflect MIM Construction's vision of creating safety for their customers.

    The generic product development process described by Ulrich and Eppinger in the book Product Development, Construction and Design has been used to generate the concept for the dog harness. This process consists of identifying requirements, generating ideas and concepts, and then selecting one or a few concepts for further development. During this process, interviews have, among other things, been carried out to identify requirements. The house of quality has been used to create the product's target specification and brainstorming has been used to find possible solutions for the dog harness. Concept selection matrices have been used to select a concept for further development. The generic product development process described by Ulrich and Eppinger has proven to be useful for concept development. The method is clear and has clear targets, customer needs have become clear early in the process to the working group.

    The concept that has been developed is a dog harness that is easy to use. The harness is mounted onto the dog by placing the harness on the ground and placing the dog's legs in the openings for the front legs. Then the harness is lifted up and clamped around the dog's chest using a zipper. The adjustment for the harness can be made easy as the harness is mounted on the dog. These properties contribute to the ease of use. The collision safety is achieved through a loop in the harness. The loop extends around the dog's chest and foreleg which is the sturdy part of the dog. The loop is connected to the car's belt system without any components in between, fewer components results in minimized amount of error sources in case of accident.

  • 267.
    Lundgren, Kristoffer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    "Fåglar i vägen": En studie av åtgärder för minskning av olycksrisk för kollision med fåglar på flygplatser2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kollisioner mellan flygplan och fåglar har inträffat i över 100 år och den första kollisionen med dödlig utgång skedde 1912. Den ökande flygtrafiken sedan början på 1900-talet har lett till allt fler kollisioner och dödsfallen inom civilflyget var mellan 1988-2015 över 200 människor. Förutom dödsfall orsakar kollisioner dyra reparationer, uppskattat till 1.2-4 miljoner dollar, samt förseningar för resenärer.Syftet med studien är att presentera lösningsförslag för att minska risken för kollision mellan flygplan och fåglar vid Trollhättan Vänersborg flygplats. Minskar fågellivet kring flygplatsen bidrar det till att skapa en säkrare miljö för resenärerna samt en säkrare arbetsplats för flyg och markpersonalen.För denna studie valdes aktionsforskning som metod. Metoden har likheter med fallstudier och kartläggningar som inleds på liknande vis. Studien är i huvudsak kvantitativ med några få inslag av kvalitativ art.För att systematiskt förstå och sätta sig in i problematiken tillämpades Sex Sigma verktyget DMAIC, som med hjälp av litteraturstudier, samt intervjuer skapade en god grund för det fortsatta arbetet. Datainsamlingen analyserades och viktades ut efter kravspecifikationen för att ta fram de lämpligaste lösningsförslagen åt Trollhättan Vänersborgs flygplats AB. Det visade sig att förslag som högre gräs kring landningsbanan och att skapa en näringsfattig miljö var de två lösningsförslagen som fick högst betyg. De två förslagen har visat sig synnerligen effektiva på andra flygplatser och dessa i kombination med en list kring landningsbanan är de lösningsförslag som anses mest lämpliga för Trollhättan Vänersborgs flygplats AB.

  • 268.
    Lundin, Johan
    University West, Department of Engineering Science, Division of Automation Systems.
    Infästningsadapter för provning av passagerarairbag2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has contained a development of a mounting adapter to be used for testing passenger airbags. The project started with the collection of customer requirements and this was done through interviews and observations of engineers and technicians at Autoliv. Phase two was to generate ideas and solutions and this was done by brainstorming. The developed solutions were ranked by using screening and a scoring matrix. The final concept from the scoring-matrix was an adapter with eight carriage bolts. A CAD model of the final concept was created. The FEM-analysis of the final concept showed that the developed adapter had low deformations and stresses during the passenger airbag deployment thus verifying that the concept can be used in the testing environment.

  • 269.
    Lundmark, Julia
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Magnusson, Sofia
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kartläggning för en effektivare pallanvändning: En studie genomförd på AkzoNobel Surface Chemistry AB2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Due to requirements from AkzoNobels customers regarding that a certain proportion of the products life must remain when delivered, and that the products has to be delivered on a special type of pallet, have created different type of problems. The company follows a principle called the full-pallet principle which means that they want to deliver full pallets as far as possible. The requirements from the company and the customer are contradictory and require a solution. To meet both of the requirements the company needs to create a clear picture of the customer's order frequency, in which extend the full-pallet principle is applied and how many packs of each product that will fit on each pallet variants. The aim of the thesis is to identify areas of improvements within the company's order processing and generating a document on which products each customer buys, and how many packages that fits on each pallet. The thesis is a development of recommendations from a previous study. Books and articles in various topics were analysed to create a theoretical framework for the thesis. Continued data collection were preformed through interviews and analysis of data from the company's ERP-system. A description of the company's current situation has been created, including description of the company's customer order process and which types of packaging and pallets that are used for deliveries. The data from the ERP-system (Enterprise Resource Planning system) were analyzed and reported in form of charts and tables regarding the company's delivery capabilities, customer distribution and supply patterns. After analyzing the company's current situation four focus areas for improvement have been identified. The first focus area is that the company should focus on reviewing their reporting management in order to obtain accurate data regarding pallet usage. Furthermore should the company analyze its distributors in order to maximize the fullness of their pallet usage. The third focus area is that customers who only order with a low order frequency, and with low purchase quantities rather should order directly from distributors. Finally, the top ten customers with the highest potential for improvement were identified. With continuous work on the identified focus areas, the company should achieve an improvement in the percentage of incomplete pallets by a third.

  • 270.
    Lycke, Liselott
    et al.
    University West, Department of Engineering Science.
    Tano, Ingrid
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Building Quality Culture in Higher Education2016In: Proceedings of the 19th QMOD-ICQSS Conference, International Conference on Quality and Service Sciences, September 21-23, pp. 939-952, Rome, Italy. / [ed] Su Mi Dahlgaard-Park, Dr. Prof., Lund University & Jens J. Dahlgaard, Dr. Prof,. Linkoping University, Lund: Lund University Library Press , 2016, p. 939-952Conference paper (Refereed)
    Abstract [en]

    Purpose - Describe an approach to build a quality culture within a Higher Education InstitutionMethodology/Approach Case study

    Findings - We show the result of the mapped processes of a Higher Education Institution; Management planning and control, Education, Research and Support, and describe how the mapping was performed, working in cross functional teams. Further on we discuss the result ofthe pilot and the plan for implementation.

    Originality/Value of paper - A process-oriented approach in a Higher education institutions, with its complexity, creates opportunities for successful quality assurance and control when having an integrated quality assurance system.

  • 271.
    Lycke, Liselott
    et al.
    University West, Department of Engineering Science.
    Tano, Ingrid
    University West, Department of Engineering Science, Division of Mathematics, Computer and Surveying Engineering.
    Building quality culture in higher education2017In: International Journal of Quality and Service Sciences, ISSN 1756-669X, E-ISSN 1756-6703, Vol. 9, no 3-4, p. 331-346Article in journal (Refereed)
    Abstract [en]

    Purpose: The purpose of this paper is to describe an approach to build a quality culture within a higher education institution. Design/methodology/approach: This paper is based on Action research and a Case study. Findings: The authors show the result of the mapped processes of a higher education institution, Management planning and control, Education, Research and Support, and describe how the mapping was performed, working in cross-functional teams. Further on, they discuss the result of the pilot and the plan for implementation. Originality/value: A process-oriented approach in higher education institutions, with its complexity, creates opportunities for successful quality assurance and control when having an integrated quality assurance system. © 2017, © Emerald Publishing Limited.

  • 272.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Klement, Uta
    University West, Department of Engineering Science, Division of Production Engineering.
    Sattari, M.
    Characterization of adhesion strenght of HVOF sprayed IN718 coatings2009In: Proceedings of th 22nd Internationa Conference on Surface Modification technolgies - SMT22. Trollhättan, Sweden / [ed] T.S. Sudarshan & Per Nylen, VALAR Docs , 2009, p. 11-18Conference paper (Refereed)
    Abstract [en]

    The tensile adhesion strength of thermally sprayed coating is conventionally evaluated via the ASTM C633-69 standard. The maximum measurable adhesion is then limited by the adhesion strength of the polymer media. High velocity oxy-fuel (HVOF) spraying can exhibit very high bonding strength and thus it is essential to develop an alternative method to evaluate coating adhesion strength. In this work a Modified Tensile Adhesion Test (MTAT) is proposed replacing gluing with induction brazing. The method was evaluated for HVOF sprayed Inconel 718 coatings deposited on Inconel 718 substrates. The effect of induction brazing process and the characteristics of the braze-coating interface was given particular interest. The results indicate that the method is superior to the ASTM C633-69 for characterisation of adhesion of coatings with high bond strength.

  • 273.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Manescu, A.
    Università Politecnica delle Marche, Ancona, Italy.
    Pirling, T.
    Laue-Langevin Institute (ILL), Grenoble, France.
    Erratum  Residual stresses distribution through thick HVOF sprayed inconel 718 coatings: (Journal of Thermal Spray Technology DOI: 10.1007/s11666-008-9242- 9)2011In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 20, no 5, p. 1140-Article in journal (Refereed)
  • 274.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Manescu, A
    Università Politecnica delle Marche, Ancona, Italy.
    Pirling, T.
    Laue-Langevin Institute (ILL), Grenoble, France.
    Residual stresses distribution through thick HVOF sprayed inconel 718 coatings2008In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 17, no 5-6, p. 915-923Article in journal (Refereed)
  • 275.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Characterization of adhesion strenght and residual stresses of HVOF sprayed Inconel 718 for aerospace repair applications2007In: Thermal Spray 2007: Global Coating Solutions: Proceedings of the International Thermal Spray Conference, Springer , 2007, p. 588-593Conference paper (Other academic)
  • 276.
    Långström, Rebecca
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Miljöutredning som verktyg i hållbarhetsarbetet2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study includes an environmental investigation at the company HMC in Västra Götaland with four centers located in different cities: Borås, Mölndal, Skövde and Uddevalla. HMC is a competence -and logistics center based on care providers' needs in the field of resources and includes various services to support the care chain. The business delivers, supplies and services all types of aids to the entire region. HMC is located under Regionservice, which in turn is part of the Västra Götalandregionen (VGR) and must therefore meet the goals and requirements that come from the top. The environmental study is a part of ensuring that HMC relates to VGR and Regionservice's new environmental plan 2017-2020. The purpose of the study is to investigate which HMC's significant environmental aspects are, and how they can / should be combined with VGR and Regionservice environmental plan for 20172020. In the beginning of the study, literature was studied related to the topic, such as environmental management systems and the impact they have on the corporation, what an environmental study is, and laws and requirements related to environmental issues. The study has been conducted using observations, surveys and interviews with employees at the various centers and data collected to quantify the environmental aspects. In total, 29 environmental aspects have been identified in the corporation and then valued using a routine template from Regionservice. At the evaluation, six environmental aspects were considered significant for the corporation, two of which were positive for HMC; conventional waste, aid, chemicals, transportation, procurement and purchasing and reuse of appliances. The study shows that HMC's corporation are well-connected with VGR and Regionservice new environmental plan for 2017-2020, the significant environmental aspects of the business can be linked to the goals set in the region. HMC should always strive to reduce its environmental impact starting with the significant environmental aspects, and to achieve all the goals, continuous improvements must be made throughout the business.

  • 277.
    Lützhöft, Margareta
    et al.
    Chalmers.
    Ljung, Margareta
    University West, Department of Social and Behavioural Studies, Division of Social Pedagogy and Sociology.
    Nodin, Karin
    University West.
    Funktionsbaserad bemanning : En förstudie 2008Report (Other academic)
  • 278.
    Magnusson, Emil
    University West, Department of Engineering Science, Division of Production Systems.
    Effektivisering av informationsflödet i en tillverkande formsprutningsfabrik2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to identify and analyze the information flow between the production, planning, and tool shop departments at a plastic injection molding company. Based on theories encompassing concepts such as overall equipment efficiency, predictive maintenance, and value flow analysis, a qualitative study has been conducted in order to determine where and to what extent information is lost within the three above mentioned departments. Interviews as well as observations have been the methods utilized for data gathering. By analyzing the collected data in a causal diagram, problems such as inadequate information on the status of the tools between the affected departments during production have been discovered. The defective information can be directly linked to the company's problems with the preventive maintenance performed on the tools. Furthermore, the information flow of the tools has been further analyzed by being tracked and documented between the relevant departments. Islands of tool information were discovered as a result of the analysis performed. The work has resulted in a recommendation for the company. The recommendation is based on enhanced functionality in the company's current ERP system. By making the status of the tools more centralized in the ERP's database, the departments concerned can gain access to important information faster that can help in the planning of preventive maintenance. The company is also recommended to review the possibilities of using the machines' current vision systems to build a more predictable predictive maintenance that could contribute to additional time savings and optimizations for the company. In order to make staff more familiar with the company's OEE, the staff should be trained in its factors and how their work affects.

  • 279.
    Mahade, Satyapal
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Curry, Nicholas
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Björklund, Stefan
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Markocsan, Nicolaie
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Nylén, Per
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Vassen, Robert
    Forschungszentrum Julich, Inst Energy & Climate Res IEK 1, Julich, German.
    Functional performance of Gd2Zr2O7/YSZ multi-layered thermal barrier coatings deposited by suspension plasma spray2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 318, p. 208-216Article in journal (Refereed)
    Abstract [en]

    7-8 wt% yttria stabilized zirconia (YSZ) is the standard ceramic top coat material used in gasturbines to insulate the underlying metallic substrate. However, at higher temperatures(>1200 °C), phase stability and sintering becomes an issue for YSZ. At these temperatures,YSZ is also susceptible to CMAS (calcium magnesium alumino silicates) infiltration. New ceramic materials such as pyrochlores have thus been proposed due to their excellent properties such as lower thermal conductivity and better CMAS attack resistance compared to YSZ. However, pyrochlores have inferior thermo mechanical properties compared to YSZ.Therefore, double-layered TBCs with YSZ as the intermediate layer and pyrochlore as the top ceramic layer have been proposed. In this study, double layer TBC comprising gadoliniumzirconate (GZ)/YSZ and triple layer TBC (GZdense/GZ/YSZ) comprising relatively denser GZtop layer on GZ/YSZ were deposited by suspension plasma spray. Also, single layer 8YSZ TBC was suspension plasma sprayed to compare its functional performance with the multilayered TBCs. Cross sections and top surface morphology of as sprayed TBCs were analyzed by scanning electron microscopy (SEM). XRD analysis was done to identify phases formed in the top surface of as sprayed TBCs. Porosity measurements were made using water intrusionand image analysis methods. Thermal diffusivity of the as sprayed TBCs was measured using laser flash analysis and thermal conductivity of the TBCs was calculated. The multi-layered GZ/YSZ TBCs were shown to have lower thermal conductivity than the single layer YSZ. Theas sprayed TBCs were also subjected to thermal cyclic testing at 1300 ºC. The double and triple layer TBCs had a longer thermal cyclic life compared to YSZ. The failed samples were cold mounted and analyzed by SEM.

  • 280.
    Malki, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Shade, Omran
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Augmented Instructions: A study of methods for utilising 3D models in technical instructions2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis intends to identify and evaluate appropriate methods for ABB Capacitors to utilise their 3D models instead of 2D representations, with the purpose of reducing costumer’s misconceptions of installation manuals. ABB spends a significant amount of time designing detailed 3D models of their products. These are later converted into 2D representations of the models to create instructions with assembly drawings to their customers. 2D representations are less detailed than the 3D models and require prior experience to give an understanding of the products design. The customers don’t always possess the required experience to install capacitor solutions accordingly, this leads to wrong installations and increased lead-time. Three new visualisation methods were identified and evaluated on behalf of ABB Capacitors requirements and prerequisites. The three methods that were identified are Video recordings, Static-rotatable-3D Model and 3D sequence video. Next step was to identify and evaluate appropriate methods to present the 3D instructions. Initially two methods were considered: Augmented Reality and Virtual Reality. During the testing phase another opportunity was discovered, animated videos with camera views. The conclusion is that ABB Capacitors should replace the current instructions with animated videos with camera views and Augmented Reality experiences. Both suggested methods were demonstrated and evaluated for ABB Capacitors.

  • 281.
    Malmsköld, Lennart
    et al.
    Chalmers University of Technology.
    Örtengren, Roland
    Chalmers University of Technology.
    Carlson, Blair E.
    SAAB Automobile, Sweden.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Instructor based training versus computer based training: a comparative study2007In: Journal of Educational Technology Systems, ISSN 0047-2395, E-ISSN 1541-3810, Vol. 35, no 4, p. 457-478Article in journal (Refereed)
    Abstract [en]

    This article describes two studies conducted to compare assembly performance and learning rate between computer based training and traditional training of skilled assembly operators. The studies were performed with pre-series production parts from a car cockpit and they were integrated as part of the overall training activities during a new vehicle product launch. The computer based training tool used was a desktop based commercial VR tool with focus on cognitive interactive procedural learning. Both studies indicate that computer based training can replace instructor based training for this level of assembly complexity and that it has a positive effect in preparing skilled operators

  • 282.
    Malmsköld, Lennart
    et al.
    University West, Department of Engineering Science, Division of Automation Systems. Volvo Technology.
    Örtengren, Roland
    Chalmers University of Technology, Department of Product and Production Development,.
    Svensson, Lars
    University West, Department of Economics and IT, Divison of Informatics.
    Improved Quality Output through Computer-Based Training: An Automotive Assembly Field Study2015In: Human Factors and Ergonomics in Manufacturing, ISSN 1090-8471, E-ISSN 1520-6564, Vol. 25, no 3, p. 304-318Article in journal (Refereed)
    Abstract [en]

    In this article, two field experiments, conducted in an automotive assembly plant, evaluate how computer-based training of operational sequences and related quality information can support the assembly performance of the operators. The experiments were performed during the launch of a new vehicle. A comparison was made of learning progress and quality performance between a reference group of operators that only had regular training and a test group for which some of the regular training was replaced with individual computer-based training. Both quantitative measures of the quality output and questionnaires and observations were used to evaluate the effects of computer-based training. The results show a clear positive difference in learning progress and improvements in quality output for the test group compared with the reference group. This combined with positive attitudes expressed by the operators and their team leaders shows that this type of training is an effective way to train operators during launches of new vehicles in automotive production. © 2014 Wiley Periodicals, Inc.

  • 283.
    Malmsköld, Lennart
    et al.
    University West, Department of Engineering Science, Division of Production Systems. Volvo Technology.
    Örtengren, Roland
    Chalmers tekniska högskola.
    Svensson, Lars
    University West, School of Business, Economics and IT, Divison of Informatics.
    Training Virtually Virtual2012In: International Journal of Advanced Corporate Learning, ISSN 1867-5565, E-ISSN 1867-5565, Vol. 5, no 3, p. 29-36Article in journal (Refereed)
    Abstract [en]

    This paper reports from a longitudinal study of a Swedish manufacturer in the automotive industry, where a series of studies have explored the potential and limitations of computer-based training of assembly operators. The study is focusing on two supplementing sets of target variables – operators' attitudes and the quality output from operators in real production. Starting with small-scale studies where proof-of-concept for virtual training is established, the research moves on to comparative studies where different computer-based learning models are contrasted and evaluated. The research design ends with large-scale field experiments assessing the effects of computer-based training in terms of quality output. The results clearly demonstrate that computer-based training, when integrated with training of standardized work procedures, outperforms traditional methods for operator training, regardless of the content and the context of the assembly operation. The findings of the study are synthesized into a design framework for virtual training where cognitive and craftsmanship training is contrasted to the learning of product, process, sequence and finesse of assembly.

  • 284.
    Mandati, Sreenkanth
    et al.
    Centre for Solar Energy Materials, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Balapur, Hyderabad, Telangana 500005, India ; Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India.
    Dey, Suhash R.
    Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Kandi, Sangareddy, Telangana 502285, India.
    Joshi, Shrikant V.
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Sarada, Bulusu V.
    Centre for Solar Energy Materials, International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Balapur, Hyderabad, Telangana 500005, India.
    Two-dimensional CuIn1−xGaxSe 2 nano-flakes by pulse electrodeposition for photovoltaic applications2019In: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 181, p. 396-404Article in journal (Refereed)
    Abstract [en]

    Fabrication of Cu(In,Ga)Se 2 (CIGS) absorber layers containing two-dimensional nano-flake structures using a single stage pulse electrodeposition technique is reported for the first time, wherein CuCl 2 , InCl 3 , GaCl 3 and H 2 SeO 3 are used as precursors in a pH 3 buffer. The method employs tri-sodium citrate as complexing agent. The phenomenon of intrinsic electrochemical dissolution associated with pulse electrodeposition technique is efficiently utilized to obtain CIGS nano-flakes. The presence of tri-sodium citrate and the relaxation time during pulse electrodeposition play crucial role in achieving control over composition and morphology of CIGS films thereby aiding in the formation of nano-flakes. Evolution of nano-flake structures is systematically investigated with the increase in deposition time during pulse electrodeposition. Elemental analysis reveals the stoichiometric composition of nano-flake films while the formation of chalcopyrite phase-pure CIGS is confirmed by XRD and Raman analyses. The bandgap of CIGS nano-flakes is inferred to be about 1.21 eV from Tauc's plot. Mott-Schottky studies unveil the p-type conductivity of the CIGS with a flat-band potential and carrier density values of −0.15 V and 5.2 × 10 16 cm −3 , respectively. Photoelectrochemical characterization of CIGS films affirms their photoactivity and the photoresponse is almost 20 times compared to the traditional planar CIGS films. Nanostructured CIGS films fabricated by low-cost pulse electrodeposition method reduce materials consumption while promising excellent photoresponse and are suitable for photovoltaic and photoelectrochemical applications. © 2019 International Solar Energy Society

  • 285.
    Markocsan, Nicolaie
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylen, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Volvo Aero Corporation, Trollhättan, Sweden.
    Xin-Hai, Li
    Siemens Industri Turbomachinery AB, Finspång, Sweden.
    Tricoire, A.
    Volvo Aero Corporation, Trollhättan, Sweden.
    Klement, Uta
    Chalmers University.
    Yao, Y.
    Chalmers University.
    Effect of Heat Treatment on Low Conductive Thermal Barrier Coatings2009In: Surface Modification Technologies XXII: Proceedings of the Twenty Second International Conference on Surface Modification Technologies Held at University West, Trollhättan, Sweden September 22-24, 2008 / [ed] T.S. Sudarshan & Per Nylen, VALAR Docs , 2009, p. 139-147Conference paper (Refereed)
  • 286.
    Markocsan, Nicolaie
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Wigren, J.
    Volvo Aero Corporation, Trollhättan.
    Li, X. H.
    Siemens Industrial Turbomachinery AB, Finspång.
    Tricoire, A.
    Volvo Aero Corporation, Trollhättan.
    Effect of thermal aging on microstructure and functional properties of zirconia-base thermal barrier coatings2009In: Journal of Thermal Spray Technology, Vol. 18, no 2, p. 201-208Article in journal (Refereed)
    Abstract [en]

    .

  • 287.
    Matsfelt, Johanna
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Study on the influence of the electrode tilt angle in GTAW doing CFD simulation of the heat source2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 288.
    Mazidi, Aimal
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Comparison of a new, high precision, energy efficient welding method with the conventional Gas Metal Arc Welding on high carbon steel base metal2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    CMT+P welding is less susceptible to hot cracking than the MAG welding process due to use of low heat input properties. Solidification cracking was found in all weld specimens that had greater 0.39KJ/mm heat inputs. Cracking occurs because of the contraction stresses generates during cooling. Hydrogen cracking is found in HAZ with low heat input parameters, this type of cracking occurred because of very rapid cooling and therefore not enough time to allow the hydrogen to dissipate from the specimen. To eliminate this type of cracking the experiment could be repeated by adding heating during welding to control and reduce the cooling rate. Due to high carbon content in the steel and very fast cooling the microstructure of the weld is martensitic in the base metal as well as the HAZ. Microstructure in the weld and base metal is martensitic due to high carbon con-tent and rapid cooling. At low heat inputs dilution is less and therefore lower carbon content in weld pool. Better weld appearance and weld quality is achieved with CMT+P welding process than the conventional GMA welding processes because of the new wire movement technology during welding

  • 289.
    Mehmood, Faisal
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Laser Welding of Aluminium in Automotive Industry2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With all the advantages aluminium (Al) carries being the light weight and sustainable material, the laser welding of Al is tricky and complicated. The major challenges in laser welding of Al are the hot cracking, porosity and reflectivity. The experiments are done in order to understand the laser welding of Al process and analyse the process parameters impacts. In this thesis work, laser welding of Aluminium alloy is done in order to understand the process parameters effects on the weld quality. Experiments are done on the 5754-H22 and 6082-T6 alloys. Welding speed and laser power is kept constant for the experiments, however, laser focus position is varied on the plates. Focus position is kept on the surface of the plate as well as above and below the surface. The butt welding of same material alloy is done on the 3 mm plates. It is been analyzed that Al alloy 6082-T6 is easier to weld and give better weld quality as compared to 5754-H22. The overlap weld is done on 1.5 mm thick plates with CW (continuous wave) welding and PW (pulse weld). The laser welding is done with high speed, therefore, CW welding shows quality weld with no significant undercut or concavity as compared to PW welding method. The focus position above the surface shows quality weld in overlap weld with both PW and CW welding methods.

  • 290.
    Molina Griggs, Alejandro José
    University West, Department of Engineering Science, Division of Welding Technology.
    Laser Metal Powder Deposition of Austenitic Stainless Steel on Spheroidal Graphite Cast Iron: A corrosion resistant coating for the Food & Beverage Industry2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Spheroidal graphite cast iron is a material widely used in the industry for the manufacturing of all kind of covers and protective casings thanks to its good combination of mechanical properties, processability and cost. When cast iron components are put into service in corrosive environments the most common approach to protect the components is painting them. The protective painting has been found to flake off with time when aggressive washing procedures, such as the ones used in the Food & Beverage industry, are applied several times.

    In this project, the coating of cast iron with a corrosion resistant AISI 316L stainless steel by Laser Metal Powder Deposition has been studied as an alternative protection against corrosion. Several samples with different combinations of substrate preparation, number of layers and surface conditions were produced and analysed by optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, wash down tests and salt spray chamber corrosion tests.

    Main results show that the diffusion of carbon from the carbon-rich cast iron to the stainless steel coating, which would have a negative effect on the corrosion resistant properties, was significantly low as a result of the low penetration and dilution achieved during the laser metal powder deposition process. The deposited stainless steel coatings successfully protected the substrate during the corrosion tests and the integrity of the coatings is not expected to fail during the washing producers applied in the industry.

  • 291.
    Molldén, Mikael
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kartläggning av projektet: ”Nyckelfritt” i Uddevalla kommun2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this report, the purpose has been to examine how a project has worked. This includes collecting data from various documents and interviews with people involved in the project, but also by observations of how the project team have been working in the project. In this report, there is a theory section in which a literature study was conducted by looking into contemporary research. The data chapter consists of interviews with 21 different participants, consisting of people working with the project, but also outside the project like people in other municipalities with similar tasks, and people in the municipality who will be affected by the project. The goal has therefore been to map out how the work has been carried out in the project, and to identify possible problems to see what can be improved for future projects, but also how to proceed with this project. In this thesis, the project group's work has been compared with a project model presented in the theory section. The reason why its compared to the project model is to provide a structure to identify how they worked with different parts of the project. This provided a complete overview of the project and a base for identifying improvement opportunities for the project. Improvements include to develop a project model to work and communication must be improved from the lead and down the line (top-down). The competence must also be evaluated before the project starts to see if additional training is needed to avoid delays in the project. Finally, project content and initiatives must be prioritized to ensure good planning and that the project manager is allocated in accordance with time required so this person will be best utilized for the project.   Date

  • 292. Murgau, A.
    et al.
    Pejryd, Lars
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    A Scientific Perspective on Improvement of Transactional Processes2006In: 39th CIRP International Seminar on Manufacturing Systems : the morphology of innovative maufacturing systems: Ljubljana, June 7-9, 2006, p. 473-478Conference paper (Other academic)
  • 293.
    Nia, Nima K.
    et al.
    Volvo Cars, VCIT, Olofström, Sweden.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Lennartson, Bengt
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    A faster collision detection method applied on a sheet metal press line2011In: The 4th International Swedish Production Symposium, Lund: Swedish Production Academy , 2011, p. 467-472Conference paper (Refereed)
    Abstract [en]

    Geometrical collision detection is a time and resource consuming simulation task. In order to decrease time and resources, a general method applicable for 2D motions has been developed. The method is useful in simulation cases where 3D CAD data is part of an iterative method, e.g. optimization. The method is based on a transformation of a general 3D problem to a 2D problem, eliminating the need of 3D CAD models. Press Line simulations during the last decade have been accepted as a quality improvement method. Today simulations of automated press lines are done for internal collision checks in dies and external collision checks against dies and material handling equipment. If these collisions are not detected in simulations, they result in delays, in introduction of a new product in the line, so called line tryout or later when the line is ramped up to decide rate. The results of these collisions are used for pre-die design, design of grippers, maintenance and production planning. In this paper a new method, based on 2D simplifications, is developed and tested successfully in a virtual model of a press line at Volvo Car Manufacturing. Die Uppers 2 917 708 triangles and Die Lowers 602 686 triangles where reduced to 58 and 90 points. The result of the method shows substantial reduction of geometry data and considerable improvement in collision detection evaluation time over general 3D algorithms in the tested case.

  • 294.
    Nilsen, Morgan
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Sikström, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    Christiansson, Anna-Karin
    University West, Department of Engineering Science, Division of Production Systems.
    Ancona, Antonio
    University West, Department of Engineering Science, Division of Production Systems.
    In-process Monitoring and Control of Robotized Laser Beam Welding of Closed Square Butt Joints2018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 25, p. 511-516Article in journal (Other academic)
    Abstract [en]

    In robotized laser welding of technical zero gap closed square butt joints it is critical to position the laser beam correct with regardsto the joint. Welding with an offset from the joint may cause lack of sidewall fusion, a serious defect that is hard to detect and gives a weak weld . When using machined parts with gap and misalignment between the parts that is close to zero, existing joint tracking systems will probably fail to track the joint. A camera based system using LED illumination and matching optical filters is proposed in this paper to address this issue. A high dynamic range CMOS camera and the LED illumination is integrated into the laser tool. The camera captures images of the area in front of the melt pool where the joint is visible and an algorithm based on the Hough transform and a Kalman filter estimates the offset between the laser spot and the joint position. Welding experiments, using a 6 kW fiber laser, have been conducted to evaluate the performance of the system. Promising results are obtained that can be used in the further development of a closed loop controlled joint tracking system.

  • 295.
    Nilsson, Emmy
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Andreasson, Gwendelines
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Åtgärdsförslag till Sansera Sweden AB för att uppfylla kraven i kvalitetsstandarderna ISO 9001:2015 och IATF 16949:20162017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, a Gap Analysis has been performed to find out how Sansera's quality management system meets the new requirements in the standards ISO 9001:2015 and IATF 16949:2016. The aim of the thesis is to make suggestions for actions that Sansera needs to take in their current quality management system in order to be certified according to the latest standards. In the Gap Analysis that was established, the standards ISO 9001:2015 and IATF 16949:2016 were compared to the previous standard ISO/TS 16949:2009 to find out what requirements are new. The requirements were then compared with Sansera's quality management system to identify the company's current situation. Based on the results of the Gap Analysis, the extent of the gaps was identified in Sansera's quality management system. In the study a benchmarking was performed against a company with similar processes like Sansera. The benchmarking was performed to verify if the methodology in this study is appropriate for its aim. The result of the benchmarking confirmed that the methodology used in the study is appropriate. Several of the requirements in the standards ISO 9001:2015 and IATF 16949:2016 requires that there should be documented information for the process that the requirement covers. The result of the Gap Analysis showed that a recurring reason for several of the gaps was that Sansera did not have the documented information for its processes required by ISO 9001:2015 and IATF:2016. Requirement 4.2.2 proved to be the most critical requirement because it can only be fulfilled if all other requirements containing requirements for documented information are fulfilled. In the study the suggestions for actions are presented to the gaps in Sansera's quality management system which is fulfilled by half, small part or not at all. The suggestions for actions are considered to be able to close the gaps in Sansera's quality management system. In order for Sansera to fulfill the gap regarding the lack of documented information, the company is recommended to update their current document management system, it is assumed to facilitate the introduction of the suggested procedures regarding documented information.   

  • 296.
    Nilsson, Patric
    et al.
    Volvo Aero.
    Appelgren, Anders
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Henrikson, Per
    Volvo Aero.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Process and Product Development.
    Automatic Ultrasonic testing for Metal Deposition2012In: Proceedings 18th World Conference on Non-Destructive Testing: 16 - 20 April 2012, Durban, South Africa, Durban, 2012, p. 1-10Conference paper (Refereed)
    Abstract [en]

    Metal Deposition (MD) is a method to build three dimensional metal geometries by welding using filler wire or powdered metal. NDT of a MD feature is required when the feature is located in an area of high stress or could be a potential hazard to the part. Ultrasonic testing (UT) can be used to detect pores, linear indications and lack of fusion in welds. This method has limitations when it comes to large parts with complex geometries with various shapes and sizes. A flexible method for inspecting complex geometries is to mount an ultrasonic water flow probe (squirter) on a robot. The robot can then follow a pre-programmed path to achieve full inspection of the feature. This paper shows results and functionality from a system where a squirter probe was used together with a standard industrial robot. Results from a scanning of a three-dimensional MD-structure are also presented.

  • 297.
    Nilsson, Per
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Konstruktion av lyfthjälpmedel till hydraulcylinder2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Among other products, JOAB Försäljnings AB manufactures hook lifts for trucks. The hook lifts are equipped with two hydraulic cylinders. These are lifted into place using round slings and chain hoists. This is not the optimal way of doing it. The reason for this is that the round sling can be incorrectly applied to the cylinder. In a worst-case scenario, the cylinder can be dropped with personal injuries and material damages as a result. The round sling may also cause damage to the cylinder paint through contact which is not desirable.  Thus, the goal of this project is to construct a lifting aid which lifts the cylinder into place in a safe way without damaging their paint. It must also meet Swedish work environment authority (Arbetsmiljöverkets) requirement for CE-marking.  To ensure that the workers will perceive it as helpful in their work, interviews and observations were done to identify their functional demands.  All demands are compiled and the concepts that meet them in various way are sketched. The best suited concept to proceed with was chosen by means of different concept selection methods. At this stage, the workers were also invited to ensure that the right concept was chosen.   Based on the chosen concept, a 3d model was developed. Relevant forces acting on the structure were identified and used in the strength calculations performed. The model was modified until a suitable balance between dimensions, material and strength was achieved. The final result is a lifting aid that will solve JOAB’s assembly problems.

  • 298.
    Nourozi, Benjamin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Ogemark, Freddie
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Undersökning av SafetyEYE för interaktion mellan människa och robot i ett mindre riskområde2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis examined if SafetyEYE is safe and reliable for human-robot interaction in a smaller area of risk. In today's industry sought flexible solutions to make the robot safe as this is now done by having a solid barrier around the robot, which prevents the flexibility of human-robot interaction. To eliminate the need of a solid barrier there is a system named SafetyEYE.

    SafetyEYE is a camera system that enables three-dimensional zone monitoring where neither human nor robot must be in the zones while the robot is operating in automatic mode.

    The purpose of this study is to examine the system's resolution, sensitivity and sensitivity to reflections in a smaller risk area of 3.8 m x 2.8 m, as the system proved to be over sensitive to reflections from reflective objects in a greater risk area in a previous work. Some other purpose of this study is to examine what the ISO standards say on the application of a system like SafetyEYE and acquire knowledge about other methods and safety systems that enable a safe HRI (Human-Robot Interaction).

    The aim of this study is to examine if SafetyEYE is safe and reliable for monitoring a smaller risk area.

    The results of dissolution experiments showed that the system can detect objects down to 2 mm in width at a distance of 3.05 meters from the camera and with an illuminance of 315 lux in the experiment area. Furthermore, the results of the sensitivity experiments showed that the system was over-sensitive when the illuminance was 15 lux and 4000 lux in the experiment area. Regarding the result of reflection experiments showed that the system was reflection sensitive when two lamps with an illuminance of 4000 lux were directed against a reflective metal and a mobile. Four ISO standards found that covered the area of application of SafetyEYE. These ISO standards covering subareas: Stop function, requirements for an HRI area, the level of performance and safety distance. Furthermore, the results of the literature review of methods and safety systems for enabling a safe HRI showed that there are similar systems like SafetyEYE.

    Conclusions were that the system is not reliable in terms of light and reflection sensitivity when used for monitoring a smaller risk area, but can be used in a work environment that is adapted to the system, such as the illuminance does not change and the floor does not reflect. After the study of the ISO standards could be concluded that it is possible to implement SafetyEYE in a robot cell according to ISO requirements.

  • 299.
    Nyberg, Oscar
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Manufacturing steel tube car seat frames: Description of the product requirements and process methods2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this thesis work has been to describe the product requirements and process methods for manufacturing steel tube car seat frames. A wire frame is commonly used in the seat padding in the back seat of a car. The wire frame currently consist of wires with dimensions 4.5 mm and 6 mm. The frame is responsible for:

     Fastening the seat in the back seat of the car (keep it in place during e.g. impact),

     Serving as a point of attachment for upholstery,

     Keeping the shape of the moulded goods

    The main goal of the report was to present a viable solution based on the following objectives:

    1. Find a standardized tube, which corresponds to the current frame and meets all the stated requirements in the problems description,

    2. Define the minimum bend radius of the intended tube dimensions,

    3. Investigate suitable method of joining the tube parts while maintaining the strength of the frame

    A viable solution is presented, consisting of two tubes with customized dimensions:

     6 mm OD x 0.5 mm wall thickness will replace the 4.5 mm wire,

     7 mm OD x 0.75 mm wall thickness will replace the 6 mm wire

    This solution results in a weight reduction of 47 %, fulfilling the requirement stating that: 'The weight of the new frame should be approximately 50 % of the current frame weight'.

    The solution presented is 27 % more expensive, but the increased cost could be financed by the automotive industry's willingness to pay for reduced weight.

    The tubes have a theoretical minimum bend radius of 3 x the outer diameter of the two tube dimensions respectively.

    The tubes will be welded using projection resistance welding. This method is currently used welding the wire frame. The current machinery will be adjusted to work with the defined tube dimensions.

  • 300.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Applications of thermal spray technology for aerospace and automotive industry2013In: Heat Treatment and Surface Engineering - Proceedings of Heat Treatment and Surface Engineering, HTSE 20132013: HT & SE 2013, 16 to 18 May 2013, Chennai Trade Centre, Chennai, India / [ed] Bakshi S.R.,Kamaraj M.,Mudali U.K.,Sudarshan T.S.,Raj B.,Murty B.S., ASM International, 2013, p. 65-68Conference paper (Refereed)
    Abstract [en]

    Thermal spraying can provide thick coatings (approx. thickness range is 20 micrometers to several mm, depending on the process and feedstock), over a large area at high deposition rate as compared to other coating processes such as electroplating, physical and chemical vapour deposition. Coating materials available for thermal spraying include metals, alloys, ceramics, ptastics and composites Thermal spraying provides engineered coating solutions for a wide range of industrial applications. The aerospace industry was one of the first to exploit the benefits of thermal spray coatings. Nowadays, thermal spray technology is used in a large number of applications within this industry meeting high performance and quality requirements. Examples of applications within the aerospace sector are landing gears, abrasion wear resistant coatings, engines (combustion liners, discharge nozzles, blades, and compressor casings), and wing structures. An emerging application area for thermal spraying is the automotive area. Examples of applications within this area are synchronisation rings, piston rings, cylinder heads, turbocharger abradables, brake discs, cylinder bores, and hard chrom replacement This talk discusses some thermal spray applications within the aerospace and automotive sectors.

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