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  • 151.
    Kachisa, Derrick
    University West, Department of Engineering Science, Division of Production Systems.
    Automation and Integration of AGC and Portal Robot: Communication and Integration in a Smart Factory Concept2020Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Smart production systems form the basis of novel interaction and collaboration opportunities between humans and their working environment. In this context, human-machine collaboration is an application area for the future shop floor and will pave the way for the new dimensions in production. This thesis highlights what is necessary to achieve the integration of resources at a shop floor with a specific contribution to communication, process planning and transportation. As this is part of larger project that is to achieve a smart factory test bed, the concepts of smart factories, industry 4.0 and the technologies that support such systems are investigated and discussed. To demonstrate this, a portal robot, automated transport system and manufacturing execution system are integrated to facilitate a kitting operation. This thesis seeks inform how a feature rich smart factory test bed with collaborative assembly can be designed, developed, and tested.

  • 152.
    Karade, Mrunmay
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Sintering behaviour of Suspension Plasma Sprayed Thermal Barrier Coatings2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thermal barrier coatings are introduced for increasing durability of metallic components used in hot section of gas turbine engines. Current requirement of the gas turbine engine is to improve the fuel economy with superior efficiency has led to a continuous increase in gas inlet temperature. However, above 1200°C YSZ had issues like poor phase stability, high sintering rates etc. which affects the TBC life. Reason behind the using SPS process has modified property than APS i.e. ability of generating columnar microstructure. At high temperature sintering changes in TC layer may lead to reduction on porosity results change in mechanical properties and thermal properties.

    This work presents sintering behaviour of suspension plasma sprayed single layered (8YSZ) TBC and multi-layered (GZ/8YSZ, 48YSZ/8YSZ, YAG/8YSZ) TBC´s at high the temperature, the influence of the substrate and changes in composition on sintering. Free standing TBC´s has positive effect on sintering as compared to TBC´s with the substrates.

  • 153.
    Karimi, Maryam
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Effect of YSZ thickness on the durabil-ity of Gadolinium Zirconate/YSZ double-layered Thermal Barrier Coating2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    7-8 wt. yttria-stabilized zirconia (YSZ) is current standard ceramic material in thermal barrier coating (TBC) applications, mainly in gas turbine engines. However, for high temperature (>1200°C) gas turbine engine operations, YSZ has limitations of poor phase stability and high sintering rates along with its susceptibility to CMAS (calcium magnesium alumino silicates) attack. These challenges effect the durability of TBCs based on YSZ top coat. A wide range of both academic and industrial researches has been done to improve TBC performance by opting for advanced TBC materials and appropriate TBC microstructure. Amongst different proposed materials, pyrochlores have shown excellent properties such as lower thermal conductivity and resistance to CMAS attack compared to YSZ. However, pyrochlores have the drawback of inferior thermo-mechanical properties than YSZ.

    To address this issue, double layered TBCs with YSZ as the base layer and pyrochlores as top layer were proposed to take advantages of high fracture toughness of YSZ and high temperature capability of pyrochlores. In this study, double layer TBC consisting of gadolinium zirconate, Gd2Zr2O7 (here after referred to as GZ), as the top layer and YSZ as the base layer were deposited. Three double-layered GZ/YSZ TBCs with different layer thickness, i.e. 100GZ/400YSZ, 250 GZ/250 YSZ and 400GZ/100YSZ (the prefixed numbers before GZ and YSZ denote corresponding layer thickness in µm) were deposited by suspension plasma spray (SPS). The intention behind varying thickness of YSZ was to alter the fracture toughness at probable failure location of double-layered TBCs (GZ/YSZ interface). The deposited TBCs were subjected to burner rig test (BRT) and thermal cyclic fatigue (TCF) test.

    It was shown that the double layer TBC with lower YSZ thickness had higher thermal cyclic fatigue life and burner rig lifetime (also known as thermal shock lifetime) compared to 100GZ/400YSZ and 250 GZ/250 YSZ. Failure analysis of the TCF specimens and burner rig tested specimens were investigated using a scanning electron microscope (SEM)/energy-dispersive spectroscopy (EDS). The failure modes in BRT were similar for the three double layered TBC variations i.e. at the GZ/YSZ interface. In the case of TCF, failure was observed in the TGO. Porosity analysis and hardness test were employed to compare the sintering behaviour of GZ and YSZ by analysing TBC specimens before and after exposure to TCF test.

  • 154.
    Karlsson, Charlie
    University West, School of Business, Economics and IT, Divison of Law, Economics, Statistics and Politics.
    Handbook of Research on Innovations and Clusters: Cases and Policies2008Collection (editor) (Other academic)
  • 155.
    Keyvani, Ali
    et al.
    University West, Department of Engineering Science, Division of Production Engineering. University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    A Virtual Manufacturing Approach for Integrating Fixture Design with Process Planning2009In: Proceedings of the sixth CIRP-sponsored International Conference on Digital Enterprise Technology: 14-16 dec, HongKong, 2009, p. 483-496Conference paper (Other academic)
    Abstract [en]

    Computer Aided Process Planning has received more attention recently due to considerable progress in the aspects of both technology and theory. Beside the traditional trends and efforts to integrate the product design and process planning activities usually referred to as concurrent engineering, virtual manufacturing tools have opened new horizons to this domain. This paper describes how to combine an existing modular fixture design with process planning and simulation tools. The proposed concurrent architecture consists of a functional model and an operational workflow for the design of modular fixtures within the process-planning phase. Two different paradigms, the Variant and the Generative, are discussed in relation to the proposed architecture. Fixtures for Body in White lines are a crucial design problem in the automotive industry. Therefore, the proposed architecture has been tested and investigated in such an environment.

  • 156.
    Khalatbari, Hosein
    University West, Department of Engineering Science.
    Robust machining with circle segment tools by considering stability2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is a growing need for geometrically complex components produced by CNC machining. Such components have vast applications in the automotive sector, aerospace industry, power generation (turbines), hydraulic devices, mold-die industries, and customized medical implants. Ballnose mill tools are conventionally used for five-axis milling of such components (e.g. bladed disks so-called blisks). These tools provide fine surface finish and flexibility in toolpath generation. However, the tool radius limits the radius of the cutting envelope. The maximum applicable tool radius is also restricted by the geometry of the component (e.g. in blisks). In addition, fine surface finish demands limited scallop height, which is obtained by adopting small values of stepover. Such constraints lead to longer processing time, whereas the competitive market calls for higher productivity. To address the problem, innovative circle-segment tools offer a significantly larger radius of the cutting envelope (engagement radius) per tool radiuses. Therefore, a significantly lower cycle time is feasible, whereas a good surface finish is preserved. The literature is scarce on robust and comprehensive simulation approaches for the modeling of the cutting forces and the prediction of dynamic stability in the five-axis milling process by using circle-segment tools. In the literature, some gaps are evident in terms of the edge (ploughing) effects, flank/slot/tip cutting scenarios, cutting coefficient calibration approaches, and the range of the process parameters studied. In the limited number of available studies, the dynamic stability criterion is either undisclosed or is merely founded on experimental outcomes without providing any analytical framework for prediction. Therefore, this study aims at developing a simulation approach for the prediction of the cutting forces and dynamic stability in five-axis milling by using circle-segment tools. The cutting-edges radius of the oval circle-segment tool was measured by employing light optical microscopy (LOM). To derive the dynamic properties of the tool and its Frequency Response Function (FRF), impact hammer tests were carried out on the tool. Three-dimensional digital twins of the cutting-edges profiles were generated in MATLAB based on one-dimensional measurements by laser and Linear Variable Differential Transformer (LVDT) sensors. An efficient tool-workpiece engagement model was developed to predict the uncut chip thickness and chip area. The cutting coefficients (shear and edge coefficients)were calibrated by adopting two methods. For this purpose, and to validate the force predictions, a series of five-axis cutting tests were performed at variable feeds (25 to 65), constant spindle speed (3500 rpm), and tilt angle (84.08º). The workpiece was additively manufactured titanium alloy blocks. To experimentally investigate the dynamic stability and chatter, several five-axis cutting tests were conducted at variable spindle speeds (3000 to 4000 rpm), depth of cuts (100 to 900 µm), and tilt angles (84.08º and 80º) along with a constant feed (55 µm). This experimental campaign involved the measurement of cutting forces, the three-axis acceleration of the workpiece, and cutting sound. The topography of cut surfaces corresponding to specific cutting conditions was investigated by employing a White Lite Interferometer (WLI). The stability map was predicted based on the calculation of dynamic chip thickness, force, and characteristic equation. For this purpose, the Nyquist stability criterion was adopted to conclude on the dynamic stability per cutting conditions, namely spindle speed and depth of cut. The Root Mean Square (RMS) of the recorded cutting force, workpiece acceleration, and surface roughness data were used to experimentally validate the predictions. The predictions of the cutting forces and stability map were acceptably validated by experimental data. The positive effect of the differential pitch, as identified in the tool, on dynamic stability was highlighted by the simulations. In addition, the effect of the ratio of the cutting edge radius to feed per tooth per revolution on the cutting coefficients and cutting mechanism was highlighted.

  • 157.
    Kisielewicz, Agnieszka
    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.
    Spectroscopic monitoring of laser blown powder directed energy deposition of Alloy 7182018In: Procedia Manufacturing, E-ISSN 2351-9789, Vol. 25, p. 418-425Article in journal (Refereed)
    Abstract [en]

    Experimental explorations of a spectrometer system used for in-process monitoring of the laser blown powder directed energy deposition of Alloy 718 is presented. Additive manufacturing of metals using this laser process experiences repeated heating and cooling cycles which will influence the final microstructure and chemical composition at every given point in the built. The spectrometer system disclosed, under certain process conditions, spectral lines that indicate vaporisation of chromium. Post process scanning electron microscope energy dispersive spectroscopy analysis of the deposited beads confirmed a reduction of chromium. Since the chromium concentration in Alloy 718 is correlated to corrosion resistance, this result encourages to further investigations including corrosion tests.

  • 158.
    Klevendal, Niklas
    University West, Department of Engineering Science.
    Robotized assembly simulation of a coupling2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this master´s thesis is to simulate a robotized assembly of a small model of VBG Group couplings. By the software; Process simulate has the simulation model built up and the simulation been done. The simulation model is built up of the coupling parts and resources; conveyor, fixtures, compress machine, grippers, nut and screw sorter. All parts and resources, except the compress machine, the fixture and cage for the shaft, have been designed under the whole project. A study on how assembly simulation works in the software has also been done.

    Download full text (pdf)
    FULLTEXT01
  • 159.
    Krantz, Marthin
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Andersson, Rikard
    Robotized Polishing and Deburring with Force Feedback Control2010Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Force control is introduced to robots to solve the problem in machining applications due to the fact that the robot compliance might cause deviation between actual and desired robot path. Also large tolerances in the casting process as well as positioning errors from the clamping create deviations for which the force control technology can adept. Force control has also shown successful in automatic learning of paths along non linear surfaces.

    This study investigates the possibility of introducing robots equipped with force control at Volvo Aero Corporation in order to robotize polishing and deburring processes. These are today performed by manual labor. This study investigates more specifically the ABB Force Control machining application package. The polishing process has shown to be very complex and today’s version of the ABB force control package cannot give sufficiently robust results to be recommended for implementation. The major issue is the non-existing compliance of tool orientation needed to adapt to casting and positioning deviations due to varying work piece dimensions. The deburring process has however shown to be easier to handle, and a robot cell and methodology is proposed in this report.

    Download full text (pdf)
    FULLTEXT01
  • 160.
    Krasniqi, Lulzim
    et al.
    University West, Department of Engineering Science.
    Moustafa, Debin
    University West, Department of Engineering Science.
    Utveckling av sorteringshjälpmedel för medicinska behållare2024Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This project is a degree project that deals with the development of sorting aids for medical containers. The project is carried out at Nolato and aims to develop and simplify the sorting of defective products for the return department. There is currently no automated solution for sorting out products and this is currently done manually.The project begins with information gathering through interviews, observations of the work process, and literature studies. The focus has been on brainstorming concepts for a deeper understanding. Different concepts are developed using a product development process.The project is broken down into subproblems before concept selection begins. First, different concepts are screened out using a concept screening matrix to eliminate less promising alternatives. The remaining concepts are then scored through a concept scoring matrix to obtain results and facilitate decision-making. This structured methodology enables a systematic and efficient handling of different ideas and concepts during the project's development phase.The concept development phase resulted in the selection of the concept “Concept D” as a solution to the project. The concept is a vision system that is considered to automate and streamline the work process. The concept presents the products to the camera using conveyor belts and trays shaped around the product. The camera inspects the product and then sorts by cavity number. After inspection, defective products are sorted out using air pressure.Due to the time frame, a full prototype of the concept was not created, tests were only carried out on the vision system and the tiles through simulations. The result should only be considered as an evaluation of the concept and simulation.

  • 161.
    Kumar, S.
    et al.
    International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India.
    Vidyasagar, V.
    International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad,India.
    Jyothirmayi, A.
    International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India.
    Joshi, Shrikant
    University West, Department of Engineering Science, Research Enviroment Production Technology West. International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), Hyderabad, India.
    Effect of Heat Treatment on Mechanical Properties and Corrosion Performance of Cold-Sprayed Tantalum Coatings2016In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 25, no 4, p. 745-756Article in journal (Refereed)
    Abstract [en]

    The cold-spray technique is of significant interest to deposit refractory metals with relatively high melting point for a variety of demanding applications. In the present study, mechanical properties of cold-sprayed tantalum coatings heat treated at different temperatures were investigated using microtensile testing, scratch testing, and nanoindentation. The corrosion performance of heat-treated coatings was also evaluated in 1 M KOH solution, and potentiodynamic polarization as well as impedance spectroscopy studies were carried out. Assessment of structure–property correlations was attempted based on microstructure, porosity, and intersplat bonding state, together with mechanical and corrosion properties of the heat-treated cold-sprayed tantalum coatings. Coatings annealed at 1500 °C, which is very close to the recrystallization temperature of tantalum, were found to perform almost as bulk tantalum, with exciting implications for various applications.

  • 162.
    Kämpe, Malin
    et al.
    University West, Department of Engineering Science, Division of Process and Product Development.
    Albertson, Peter
    University West, Department of Engineering Science, Division of Process and Product Development.
    Design for Manufacturing: för produktionsanpassad konstruktion på Volvo Aero2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the Bachelor’s Thesis was to create a tool for the gathering of experience data for the product development process. It should contribute to a systematic operation approach at Volvo Aero Corporation. It should also contribute to improve productivity and producibility on future concepts. The problem described in the Bachelor’s Thesis is based on a pre-study performed at the company during the autumn 2010.

    The general task was defined as develop a structure for re-use of manufacturing experience and to create a test version of the tool for evaluation. After consultation with the selected Business Development-group from department 9931 Project-, Concept- and Manufacturing-leaders, the task was limited to gathering information of diameter dimensions from the Diffuser Case component at Volvo Aero. The creation of the tool had its starting-point in current production and the information available there.

    The Design for Manufacturing-tool has been created in Microsoft Excel and it’s developed in a way making it possible to gather and present information from different systems and sources. The tool presents the information in a pedagogical way that makes it user-friendly. The structure of the tool has been developed in consultation with the Business Development-group and the 35 columns of information is classified in three different groups: basic facts, capability and cost, operation time. By this classification the information level of detail increases from left to right which enables a more structured and systematic way of working. The knowledge, experience and data gathered represent information about the requirements the company currently produces. Over time, the Design for Manufacturing-tool is to be filled with more information from strategically chosen components which coincide with the direction the company has chosen for the development of new components.

    Download full text (pdf)
    Design for Manufacturing - för produktionsanpassad konstruktion på Volvo Aero
  • 163.
    Köhler, Veronica
    University West, Department of Nursing, Health and Culture.
    Co-Creators of Scope of Action: An exploration of the dynamic relationship between people, IT, and work in a nursing context2006Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Information Technology (IT) is today widespread in our work places, in our spare time and in our society overall. Implementations of IT in organizations come with high expectations on effectiveness, revenue, smoother work processes and so on. However, this simplified view on IT ignores the fact that it is the IT usage rather than the IT artifact per se that in the end decides the effect of an implementation of IT. Although the IT artifact certainly has been designed to support certain tasks and processes, the success or failure of the Information System (IS) in the end depends on the individuals' actions, which ultimately depend on their perceptions and interpretations of the IS. Thus, when technology is being implemented and becomes an IS in use, it becomes a part of work, and as such more of a social system than a technological one.

    The actual result of a design process does not solely consist of things or artifacts, but above all changed action patterns for the users. From this follows that we must consider design of artifacts as something more than merely the constructing of actual objects with functions and properties that are easily measured. Rather, a large part of all design activities has to do with design of conceivable social milieus, not artifacts. Thus, design may be defined as the suggesting and establishing of scope of action. The concept scope of action aims at describing the fact that the design of, and consequently the implementation of, a specific IT artifact always aims at creating a certain scope of action; some actions are made easier, others are made more difficult or even impossible. This scope of action has to some extent been deliberately designed, but these changes may on the other hand also be undesired and not predicted in advance. The complexity of this phenomenon is great and hard to grasp in advance. However, this does not mean that we can allow ourselves to ignore exploring this phenomenon more deeply. On the contrary, with a usage perspective on IS success or failure, scope of action becomes very important.

    Although the term scope of action may seem a rather intuitive concept, we need more concrete knowledge about its character in order to be able to understand IT usage, both when designing a new IT artifact and when studying or evaluating IT. Thus, our intuitive understanding of the concept needs to be complemented with theory on the ‘constituents’ and effects of this phenomenon. For this purpose, in this thesis nurses’ use of the Electronic Patient record (EPR) is being explored in order to gain an empirically derived understanding of the character of scope of action.

    The research findings highlight the emergent character of scope of action. It is obvious that an individual’s scope of action is not being created on one occasion, and above all not only by the IT artifact. Various co- creators such as the IT artifact, the usage and the social context create and re-create scope of action. Also, how the individual interprets and understands the IT artifact in IT usage will influence her scope of action. This since sensemaking and learning processes on both a personal and organizational level take place that are co-creators of the individual’s scope of action, at the same time as the individual’s knowledge and previous sensemaking and learning influences her use of the IT artifact.

    Thus, reasoning, thinking, learning, and the IT artifact co-evolve over time in adaptation and appropriation processes. This means that IT as a mediational means constitutes an important co-creator of scope of action. From this also follows that work integrated learning is an important co- creator of scope of action when using IT in a work setting, at the same time as work integrated learning is being influenced by the individual’s scope of action.

    Finally, in order to understand how scope of action emerges in use, merely focusing on structures is insufficient. Scope of action emerges as a product of interplay between complex processes involving artifacts, usage and context. This means that the user’s scope of action is co-created by both static structures as well as dynamic processes relating to the IT artifact, the organization, and the work practice. Thus, the IT artifact, and subsequently scope of action, must be must be understood in relation to the multi-aspectual context of which it is a part instead of merely in relation to the properties of the IT artifact per se.

  • 164.
    Lagrosen, Yvonne
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Grundén, Kerstin
    University West, School of Business, Economics and IT.
    Tosteby, Jonas
    University West, Department of Engineering Science.
    Exploring the OCN method as a means of organizational learning2012In: Exploring the OCN method as a means of organizational learning, 2012Conference paper (Refereed)
    Abstract [en]

    Purpose -. The aim of the paper is to examine whether the use of the OCN-method also leads to organizational learning. The studied organisations are one municipality (Lerum) in west Sweden and one nonprofit professional Swedish organization, the Swedish Association of Body workers.

     

    Methodology/approach - The empirical data are derived from two focus group interviews of selected employees having different functions in the studied organisations and one in-depth interviews. The interviews are analyzed in accordance with grounded theory.  We also examine which strengths and possibilities for improvements the OCN-method has regarding organisational learning.

     

    Findings -  The interview questions are semi-structured and examine the degree and type of learning that is created by using the OCN-method. Using open-ended questions is assumed to be well suited for research in new areas.  The findings from the interviews are related to the five disciplines of the learning organisation.

     

    Research limitation/implication- The empirical data is limited to two different kinds of organisations. It would be of general interest to examine whether the usage of the OCN-method also contributes to learning in organisations.   

     

    Orginality/value - The connection between the OCN -method (Open College Network) and the learning organisation is not very well examined.

     

  • 165.
    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)
  • 166.
    Lindqvist, Jonna
    University West, Department of Engineering Science.
    Effektivisering av ett material- och monteringsflöde2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete utfördes under vintern 2022 i syfte att undersöka hur ett material- och monteringsflöde är uppbyggt, för att effektivisera flödet genom att öka det värdeskapande arbetet, minska det icke-värdeskapande arbetet av slöseri och förbättra arbetsmiljön. En fallstudie som baserades på flertalet intervjuer, observationer och verktyg genomfördes på ett material- och monteringsflöde hos Parker Hannifin Manufacturing Sweden AB Trollhättan. Det utvalda flödet var i dagsläget utformat för en lågvolymstillverkning vilket skapat problem för dagens höga orderingång. Problembeskrivningen utformades för att ta fram koncept för att effektivisera material- och monteringsflödet.

    Konceptutvecklingen baserades på en litteraturstudie av logistik, lean och arbetsmiljö. Koncepten utformades för att lösa faktiska problem som framgick ur fallstudien. För att uppfylla målet att ta fram ett koncept som bidrar till att effektivisera ett material- och monteringsflöde genom att öka värdeskapande arbete och förbättra arbetsmiljön.

    Flertalet koncept utformades och värderades mot en kravspecifikation med kriterier för att slutligen resulterade i ett slutgiltigt konceptval. Det slutgiltiga koncept valet som rekommenderades till Parker blev en kombination av flera koncept, för att ta fram det optimala förslaget för hela flödets effektivitet. Koncepten som kombinerades var: ett parallellformat flöde för att möjliggöra enstyckstillverkning med banor för att möjliggöra en balansering av både en och två personer. Banorna innefattade fasta arbetsbänkar med avsedda verktygstavlor för att eliminera slöseri av onödiga rörelser och transporter av artiklar och verktyg. För att minska manuell hantering föreslogs även en fast lyftanordning för att möjliggöra parallell användning av lyftverktyg. Slutligen kombinerades en ny ruttplanering för satsningen samt nykonstruerade vagnar för att minska onödiga transporter och manuell skjuvning av material. Slutsatser som drogs efter genomfört examensarbete var att det finns flera faktorer som påverkar ett flödes effektivitet. Men även att icke-värdeskapande arbete inte bara är slöseri utan även kan vara nödvändig för personalen och verksamhetens långsiktighet eftersom det är viktigt med en hållbar arbetsmiljö.

    Slutligen kan det konstateras att resultatet av det valda arbetssättet och metoderna genom bland annat att anpassa produktutvecklingsmetoden inom ett annat område och syfte än det som beskrivs av Ulrich m.fl. (2014) går att tillämpa på olika typer av flöden. 

  • 167.
    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.

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  • 168.
    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)
  • 169.
    Lundh Snis, Ulrika
    et al.
    University West, School of Business, Economics and IT, Divison of Informatics.
    Arghavan Shahlaei, Charlotte
    University West, School of Business, Economics and IT, Divison of Informatics.
    Hattinger, Monika
    University West, Department of Engineering Science, Division of Production Systems.
    Knowing the Practice of Industry 4.0 Through Industrial Work-integrated Learning2019In: Book of abstracts: 11th International Conference on Research Work & Learning (RWL11), 2019, p. 72-73Conference paper (Refereed)
    Abstract [en]

    In this article we analyze three manufacturing organizations' manifested expressions of different workplace initiatives related to industry 4.0. Key representatives in these organizations raise their concerns regarding changed content and forms of work as an answer to increased automation and digitalization. The wave of industry 4.0 includes smarter industrial solutions such as internet-based networks so that organizations can use connectivity of machines that can tie product development and continuous data productionwith the factory environment in new ways. Hence, the industrial work environment is under restructuring and industrial companies' work conditions are being transformed. In this article we ask the question: How do industry practitioners that currently are engaged in the transformation processes related to industry 4.0 initiatives perceive their work? Based on interviews with key representatives of three global manufacturing companies we will discuss 73 implications for industrial work-integrated learning (I-WIL) that takes into account the companies' transformative need to rethink their industrial operations and learning mindsets. We found that the introduction of disruptive digital technologies drastically changes the companies' operations. Leaders' management needs to be synchronized with practitioners' new work situations and their learning opportunities.

  • 170.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    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.

  • 171.
    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)
  • 172.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    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)
  • 173.
    Lyphout, Christophe
    et al.
    University West, Department of Engineering Science, Division of Production Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    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)
  • 174.
    Lövhall, Johannes
    University West, Department of Engineering Science.
    Process parameter optimisation for Waspaloy using Laser-Directed Energy Deposition with Powder2024Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Material utilisation is of importance in the manufacturing industry formaking the most of each material, minimising waste and increasing cost-effectiveness. In this thesis, samples of Waspaloy built with the method of L-DED-P has been analysed in order to investigate how process pa-rameters influence the build quality and geometrical accuracy in as-builtobjects. The samples analysed was built in single rows of one, three,five and fifteen layers. A build process was used in which the sampleswere built with individual combinations of the process parameters laserpower, scanning speed, and powder flow. Each combination of processparameters was used to build one track for each layer height.Analysis included defect analysis with light optical microscopy, andpost-processing with ImageJ for automatic identification, quantification,and collection of measurements. A qualitative analysis was performed andthe sample properties and characteristics was described in terms of theamount of defects, including a descriptive assessment of defect severity.Etched samples revealed a columnar grain structure in samples, which was apparent in builds with at least three layers.The results presented show a difference in build height, quantity andsize of pores, and the presence or absence of other defects such as lack of fusion. Sample 3 which was built with high laser power, slow scan-ning speed, and high powder feed show promising results with one ofthe highest build rates of all samples, combined with a low normalisedpore distribution. The sample experiences partial hardening, with hard-ness values reaching 320 HV, but still promisingly show no sign of crackformation.It is concluded that powder feed relates primarily to the build rateof the samples, and the scanning speed together with the laser power influence the quality of the build, where high laser power and low scanningspeed tends to form well behaving samples with few defects, whilst other combinations increase the risk of defects.

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  • 175.
    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.

  • 176.
    Malmsköld, Lennart
    et al.
    University West, Department of Engineering Science, Division of Production Systems. 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

  • 177.
    Malmsköld, Lennart
    et al.
    Chalmers University of Technology, SAAB Automobile AB.
    Örtengren, Roland
    Chalmers University of Technology.
    Carlson, Blair E
    SAAB Automobile AB.
    Svensson, Lars
    University West, School of Business, Economics and IT, Division of Computer Science and Informatics.
    Preparatory virtual training of assembly operators: an explorative study of different learning models2007In: Proceedings of Swedish Production Symposium (SPS) 2007, 2007Conference paper (Other academic)
    Abstract [en]

    This paper presents a study aimed at developing an understanding of how preparatory computer based learning activities can affect the operators’ ability to develop skills for new assembly operations. The study explores two computer based learning models and their potential as a preparation method for making cognitive learning related to new assembly operations more effective. The results indicate that one of the learning models investigated has advantages regarding competence level for the expert/instructor as well for the common understanding of new operations within a team of five operators and a team leader.

  • 178.
    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.

  • 179.
    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, 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.

  • 180.
    Massouh, Bassam
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Ramasamy, Sudha
    University West, Department of Engineering Science, Division of Production Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Production Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    A Framework for Hazard Identification of a Collaborative Plug&Produce System2022In: Communications in Computer and Information Science, ISSN 1865-0929, E-ISSN 1865-0937, Vol. 1616 CCIS, p. 144-155Article in journal (Refereed)
    Abstract [en]

    Plug&Produce systems accept reconfiguration and have the attribute of physical and logical flexibility. To implement the Plug&Produce system in a manufacturing plant, there is a need to assure that the system is safe. The process of risk assessment provides information that is used to implement the proper safety measures to ensure human and machine safety. An important step in the risk assessment process is hazard identification. Hazard identification of Plug&Produce system is unique as the hazard identification method provided in the safety standards do not consider system flexibility. In this paper, a framework for hazard identification of a collaborative Plug&Produce system is presented. A study case that includes a collaborative Plug&Produce system is presented and the framework is applied to identify the system’s hazards. Also, the generalisation of the framework application is discussed. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

  • 181.
    Mattsson, Sandra
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Product Realisation Methodology.(Produktion och arbetsmiljö).
    Hattinger, Monika
    University West, Department of Engineering Science, Division of Production Systems.
    Designing digital support for operator and maintenance personnel cognition and future skills in manufacturing industry2022In: INTED 2022 Proceedings: 16th International Technology, Education and Development Conference Online Conference. 7-8 March, 2022. / [ed] Luis Gómez Chova, University of Valencia, Spain; Agustín López Martínez, University of Barcelona, Spain, Ignacio Candel Torres, Capgemini, Spain, 2022, p. 9665-9673Conference paper (Other academic)
    Abstract [en]

    Industry 4.0 is believed to introduce new smart digital tools which transform manufacturing processes but affect production personnel’s work practice. Operators and maintenance personnel running the everyday operations need to learn and handle new routines and systems while maintaining production efficiency. Operators today are challenged when they must handle unexpected stops caused by machine failures and the following error recovery process of automated production systems. With complex digital tools and integrated production systems the error recovery process becomes complex because there is no one-size-fits-all solution and a lack of intelligent and automated restart systems. Even if there are defined routines for industrial work and structures for managing digital technologies, it is not adapted to the individuals’ cognitive processes neither to their workplace learning. Altogether it puts high pressure on operators’ knowledge and skills of restarting machines and systems caused by errors. The aim is to explore operators and maintenance personnel cognition and skills and how their roles vary in relevant aspects of situational awareness and workplace learning. In an on-going case we studied two industrial companies that produce similar components but are working differently with production and maintenance. Through nine interviews we investigate the differences between the companies, their current work practices, and future changes. With application of a situation awarenessmodel, we capture cognition and learning including task/system factors, perception and decision making, and individual factors. Perspectives of workplace learning and knowledge sharing between personnel and relations to the systems use are applied. Results indicate that rule-based behaviours are key for both operators and maintenance personnel. These behaviours are supported by the systems and routines, but complicated errors make the systems and routines prove inadequate. In conclusion, to design appropriate digital support tools both operators and maintenance personnel behaviour need to be supported, however they need to be supported differently since their function behaviours such as routines, system use and communication vary. In addition, future skills and competences needed forsupporting complex system tasks include knowledge of computational models and simulation, knowledge of the machines and how they interrelate with systems, and logic reasoning and robotic programming of automated production systems.

  • 182.
    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

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  • 183.
    Mertinger, V
    et al.
    University of Miskolc, Miskolc (HUN).
    Varbai, B.
    Budapest University of Technology and Economics, Budapest (HUN).
    Adonyi, Yoni
    University West, Department of Engineering Science, Division of Welding Technology.
    DeBacker, J.
    TWI Ltd., Cambridge (GBR).
    Nagy, E.
    University of Miskolc, Miskolc (HUN).
    Lesko, M.
    University of Miskolc, Miskolc (HUN).
    Karpati, V
    University of Miskolc, Miskolc (HUN).
    Microstructure evaluation of dissimilar AA2024 and AA7050 aluminum joints made by corner stationary-shoulder friction stir welding2022In: Welding in the World, ISSN 0043-2288, E-ISSN 1878-6669Article in journal (Refereed)
    Abstract [en]

    Fillet welds made by the corner stationary-shoulder friction stir welding process between AA7050-T7451 and AA2024-T4 sheets were characterized using different metallographic techniques and mechanical testing. Robotic welds of an aircraft’s skin-to-internal stiffeners were examined using Barker’s electrolytic and Keller’s etching techniques and correlated with electron backscattered diffraction results and energy-dispersive microprobe analysis. The composition and grain orientation maps and material flow lines demonstrated excellent weld quality in spite of the apparent inhomogeneities in the stir zone where mechanical mixing was complete. Welded joint efficiencies were in the 85-92% of the base metals and were acceptable in terms of resistance to crack initiation and propagation and corrosion resistance, even with softening of the heat-affected zones. It was concluded that several optical and electron microscopy techniques are needed to characterize these dissimilar aluminum welds fully and that post-weld mechanical and thermal treatments could even further improve their quality.

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  • 184.
    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.

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  • 185. 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)
  • 186.
    Najafi, Ehsan
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Understanding the effect of material composition and microstructure on the hot corrosion behaviour of plasma sprayed thermal barrier coatings2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thermal barrier coatings (TBC) are used in the hot sections of gas turbine engine in order to insulate the substrate at high temperature. Molten salt infiltration retards the durability of TBCs. The current standard material, i.e. 8YSZ is susceptible to molten salt infiltration. Therefore, alternate TBC materials are desirable. In addition to material composition, the TBC microstructure plays an important role in mitigating molten salt infiltration. Therefore, in this work, three different TBC variations were investigated. The first variation was a columnar microstructured 48YSZ TBC processed by SPS (48YSZ-SPS). The second variation was a columnar microstructured 8YSZ TBC processed by SPS (8YSZ-SPS), and the third variation was a lamellar microstructured 8YSZ TBC deposited by APS (8YSZ-APS).

    The as-sprayed TBC specimens were characterized by SEM/EDS, porosity analysis and XRD measurements. Later, the TBC specimens were exposed to hot corrosion test and their interaction with the molten salts were investigated using SEM (EDS and XRD). It was shown that an increase in stabilizer content (yttria content) in zirconia (in the case of 48YSZ) leads to an improved hot corrosion resistance due to the adequate amount of yttria content, which restricts the molten salt infiltration by forming needle like YVO4 phase. In terms of microstructure comparison, the infiltration behavior was similar for columnar microstructured 8YSZ and lamellar microstructured 8YSZ-APS as the molten salts infiltrated the coatings completely compared to the 48YSZ TBC. Furthermore, it seems that the molten salt infiltrates the TBC through globular pores, delamination cracks and splat boundaries in the case of APS-TBCs whereas the column gaps favor easier infiltration of molten salts in the case of columnar microstructured SPS processed TBCs.

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  • 187.
    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.

  • 188.
    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 (Refereed)
    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.

  • 189.
    Nilsson, Anders
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    Bennulf, Mattias
    University West, Department of Engineering Science, Division of Production Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Production Systems.
    A Classification of Different Levels of Flexibility in an Automated Manufacturing System and Needed Competence2021In: Towards Sustainable Customization: Bridging Smart Products and Manufacturing Systems: Proceedings of the 8th Changeable, Agile, Reconfigurable and Virtual Production Conference (CARV2021) and the 10th World Mass Customization & Personalization Conference (MCPC2021), Aalborg, Denmark, October/November 2021 / [ed] Ann-Louise Andersen, Rasmus Andersen, Thomas Ditlev Brunoe, Maria Stoettrup Schioenning Larsen, Kjeld Nielsen, Alessia Napoleone, Stefan Kjeldgaard, Springer Science and Business Media Deutschland GmbH , 2021, p. 27-34Conference paper (Refereed)
    Abstract [en]

    Mass customization has become more attractive but requires a transformation towards more flexible solutions in contrast to dedicated manufacturing systems. Flexibility includes complex tasks such as the introduction of new products or new manufacturing processes as well as to efficiently handle daily balancing. The main challenge when it comes to flexibility in manufacturing is to be able to handle the technical aspects and still be competitive. In this article we consider the cost for flexibility to include two main things; (1) setup time, e.g., time for planning, design, programming and configuration, installation, ramp-up, scrapping of old equipment, preparation of facility, hardware installation, and (2) need of competence, inhouse knowledge, external competence, or external expert competence. This article presents an overview of available solutions and the level of flexibility and the level of competence that is needed for a reconfiguration one can expect out of a specific solution. Further, most of the existing solutions found do not consider or address the full problem of flexibility. However, we describe a possible future of industrial concept: Plug & Produce, which can address flexibility within manufacturing more completely and sustainably over time. Methods for configuration instead of programming are developed by University West. 

  • 190.
    Nilsson, Anders
    et al.
    University West, Department of Engineering Science, Division of Production Systems.
    Danielsson, Fredrik
    University West, Department of Engineering Science, Division of Production Systems.
    Svensson, Bo
    University West, Department of Engineering Science, Division of Production Systems.
    Customization and flexible manufacturing capacity using a graphical method applied on a configurable multi-agent system2023In: Robotics and Computer-Integrated Manufacturing, ISSN 0736-5845, E-ISSN 1879-2537, Vol. 79, article id 102450Article in journal (Refereed)
    Abstract [en]

    This article proposes a Plug & Produce and goal-oriented configurable multi-agent system that admits adding and removing resources to balance the manufacturing capacity without doing any digital reconfiguration or reprogramming. To handle that a new part-agent strategy is developed and described. Goals are central in designing autonomous multi-agent systems, possibilities to execute goals in parallel are desirable when the process requirements admit concurrent use of resources. Also, a standardized graphical method, the sequence of goals chart, is proposed to define and visualize parallel and sequential goals independently of available resources. Premanufacturing of wooden houses belongs to one of many manufacturing industries that claim flexible automation systems due to the high degree of customized products and a fluctuating market. A physical Plug & Produce robot-based workstation was built up to verify the flexibility in altering capacity and adoption to product modifications of a house wall section. Further, the simplicity of modifying the proposed configurable multi-agent system was compared to more traditionally designed systems and plain multi-agent systems with superior results. The flexibility is built into the proposed system by default as a part of the concept, simple enough to be handled by existing in-house knowledge within manufacturing companies. 

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  • 191.
    Norström, Livia
    et al.
    University West, School of Business, Economics and IT, Division of Media and Design.
    Arghavan Shahlaei, Charlotte
    University West, School of Business, Economics and IT, Divison of Informatics.
    Johansson, Lars-Olof
    University West, School of Business, Economics and IT, Divison of Informatics.
    Islind, Anna Sigridur
    Reykjavik University, School of Computer Science, Iceland.
    Lundh Snis, Ulrika
    University West, School of Business, Economics and IT, Divison of Informatics.
    New Logics of Ethics in the Age of Digital Platforms: Design Fictions of Autonomous Cars2019In: Proceedings of the 17th European Conference on Computer-Supported Cooperative Work-Demos and Posters, European Society for Socially Embedded Technologies (EUSSET) , 2019, Vol. 3Conference paper (Refereed)
    Abstract [en]

    Autonomous cars are the first major examples of Artificial Intelligence (AI) in everyday life. When cars are transformed into platforms,new service relationships emerge between car companies and the car users. These relationships generate gains and catches for both parts related to how physical and non-physical resources are exchanged in the sharing economy; how integrity is negotiated; and how responsibility is delegated when AI enables the car to take over most of the driving. With a "car as a platform approach", in this paper, we present a design fiction on ethical implications for citizens' daily lives with autonomous cars

  • 192.
    Nyberg, Eleonore
    University West, Department of Engineering Science, Division of Production Systems.
    Modelling of production flow at Siemens Energy: Digital Twin with a view towards real time data implementation2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The background for this thesis stems from a wish to move the production a step further towards Industry 4.0 at Siemens Energy Trollhättan. They wish to start making this journey by researching the possibilities of simulating their production flows and extending that simulation into a Digital Twin, with alarms helping to optimise their production. In this thesis, the focus will lie on the Digital Twin towards implementation of Real Time Data within that, while the focus on alarms will be handled in the partnering work performed by Niklas Hansson [1].

    The simulation model produced within this degree work came to encompass one of the initially six suggested production flows at the Siemens factory. The data has been prepared so the expansion of the model can proceed without any major difficulties. According to theory, the model has been proven to have a high level of accuracy, the throughput only missing the calculated one with five percent. This means that the simulated model behaves in a way closely related to the actual factory floor.

    One of the most interesting results found by experimenting with the simulation is that if too many products are initialised in the system the output will actually decrease. Beyond experiments pertaining to the inflow of products, other parameters were tested as well. The chosen parameters to test were changes in sick leave, size of the workforce, scheduling, and buffer sizes. The scheduling, and as mentioned before, the inflow, were the parameters that most greatly affected the yearly production, parameters such as sick leave almost having no visible effect at all. This is thought to be because of the small scale of the current simulation, if more production flows would have been added, a greater effect would have been seen. Although no clear solution for the task of implementing Real time with a simulation was reached within the timeframe of this degree work, a solid understanding of what needs to be further researched and implemented has to be summed up in the thesis.

  • 193.
    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.

  • 194.
    Okorie, Walter
    University West, Department of Engineering Science, Division of Production Systems.
    Feasibility of joining Cast and Extruded aluminium alloys using Friction Stir Welding2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose: The purpose of this thesis work is to evaluate the feasibility of producing similar joints of AA6005 extruded aluminium alloy and dissimilar joints of AA6005 extruded aluminium alloy and AC 43500 aluminium casting by using friction stir welding as well as to investigate the mechanical properties of the friction stir welds with varying process parameters, speed optimization and the development of workable process parameters of the base materials for industrial use.

    Design/methodology/approach: The friction stir welded joints were produced using ESAB Rosio, a FSW robotic equipment with temperature control systems and tool-work-piece-thermocouple used for temperature measurement. Mechanical testing such as hardness, tensile and bending test was carried out and correlation with the process parameters was investigated. Optical microscopy (OM) was used to evaluate the joint macrostructure.

    Results: Workable process parameters were successfully achieved for the proposed base materials with the joints exhibiting good mechanical properties and joint efficiency within the accepted criteria according to ISO 25239. Good material mixing was also observed in the FSW joint macrostructure. Joint line remnant (JRL) which is classified as a feature in FSW joints was found and analysed in similar joints. Wider heat-affected zone (HAZ) was observed in the joints produced at lower welding speed compared to the joints produced at higher welding speed.

    Implications: Producing FSW joints at higher welding speed or optimized process parameters will be beneficial to cost reduction and increased efficiency of the operation.

    Value: The results of this thesis work can be used as a basis for weld procedure development on industrial applications. Useful for further studies to investigate the feasibility of producing joints at higher welding speed with good joint properties. Also, improve the efficiency of the process.

  • 195.
    Olsson, Anna Karin
    et al.
    University West, School of Business, Economics and IT, Division of Business Administration.
    Eriksson, Kristina M.
    University West, Department of Engineering Science, Division of Production Systems.
    Carlsson, Linnea
    University West, School of Business, Economics and IT, Divison of Informatics.
    A co-workership approach on digital transformation: Towards smart manufacturing2022In: Proceedings of the International Association for Computer Information Systems - Europe June 23, 2022: Virtual Conference, International Association for Computer Information Systems, 2022Conference paper (Other academic)
    Abstract [en]

    Digital transformation refers to the process of organizational change, evolving over time for value creation and appropriation aiding for smart manufacturing (Skog, 2019). Regarding the role of organizational means, there is an embedded dynamic generator of challenges, opportunities, and resources that affect the digital transformation at various organizational levels related to social factors such as values, culture, and trust (Ibid). Earlier studies of the Swedish manufacturing industry imply that as the number of digital technologies increase within organizations, while striving towards becoming a smart factory, cooperation and social factors become more imperative (Björkdahl, 2020). By following this reasoning, understanding organizational prerequisites that facilitate the human-centric perspective in relation to digital transformation is crucial when approaching smart manufacturing by moving from Industry 4.0 (I4.0) towards Industry 5.0 (I5.0) (Navarandi, 2019). It is argued that a prerequisite for digital transformation is the employees’ ability to cross organizational boundaries both horizontally and vertically (Carlsson et al., 2022) challenging management. The aim of this study is to explore organizational prerequisites for co-workership in digital transformation towards smart manufacturing. The concept of the co-workership wheel reflects the employee as an autonomous actor within the organization. As such, co-workership is vital for managing organizational change, e.g., digital transformation, capturing employees’ initiatives and prospects (Andersson, et al. 2021). As illustrated in Figure 1 the co-workership wheel consists of four conceptual pairs: Trust and Openness; Community Spirit and Cooperation; Engagement and Meaningfulness; Responsibility and Initiative. Together these four pairs describe the foundation for co-workership within the organization, feedbacking a development process towards smart manufacturing.

    Inspired by the application of the co-workership wheel in the health care sector (ibid), this study builds on previous work by Carlsson et al. (2022) to further contribute to the exploration of co-workership in the manufacturing sector strengthening the I5.0 emerging research. By applying a qualitative case-study, organizational prerequisites for co-workership in digital transformation are explored (Yin, 2018). The term co-worker is herein applied in a general sense to explore employees’ experiences covering both managerial levels and service functions. The case company is a large manufacturing organization in the Swedish energy sector. In-depth interviews (n=29) were conducted over nine months (Oct. 20 – Jun. 21), exploring co-workers' current and retrospective experiences of the early phases of digital transformation. Referral sampling was applied for selecting informants from functions such as design, quality, production, logistics, digitalization development leaders, and corporate service functions including HR, IT, and financial controllers. Access was granted to six internal documents guiding all employees covering the organization’s strategic work with industrial digitalization, vision, and core values: responsibility, excellence, and innovation. Several rounds of data analysis followed, identifying organizational prerequisites related to each of the four conceptual pairs (Andersson et al., 2020) through a coding scheme based on the co-workership wheel, Findings show that employees interpreted digital transformation as difficult to navigate due to limited communication and cooperation across the organization. Furthermore, the need for trust in digital technologies and employee engagement for transformation are emphasized by informants. Thus, it is argued that an adaptive organizational culture and a focus on learning and competence are necessary organizational prerequisites for translating the means of digital transformation. Managers in the manufacturing sector hence need awareness and understanding of when and how to apply co-workership for transformational change. Manufacturing cultures need to absorb a more human-centric perspective when navigating I4.0, moving in incremental steps encompassing the whole organization, rather than treating digital transformation as scattered and disruptive activities. We argue that the findings give useful implications for manufacturing organizations navigating the challenges of digital transformation to reach the benefits of smart manufacturing. As digital transformation cuts across organizational structures and working processes, there is a need to highlight a human-centric perspective on smart manufacturing by applying the conceptual pairs of the co-workership wheel. Lessons learned show that by applying a co-workership approach with its aspects of trust and openness, community spirit and cooperation, engagement and meaningfulness, responsibility and initiatives, management needs to encourage organizational prerequisites such as an adaptive culture and learning and competence for reaching and sustaining a human-centric perspective on digital transformation.

  • 196.
    Olsson, Anna Karin
    et al.
    University West, School of Business, Economics and IT, Division of Business Administration.
    Eriksson, Kristina M.
    University West, Department of Engineering Science, Division of Production Systems.
    Carlsson, Linnea
    University West, School of Business, Economics and IT, Divison of Informatics.
    Management toward Industry 5.0: a co-workership approach on digital transformation for future innovative manufacturing2024In: European Journal of Innovation Management, ISSN 1460-1060, E-ISSN 1758-7115, p. 1-20Article in journal (Refereed)
    Abstract [en]

    Purpose –

    The purpose is to apply the co-workership approach to contribute guidelines for manufacturing managers to exploit the potential of digital technologies through a human-centric perspective.

    Design/methodology/approach –

    A longitudinal single case study within manufacturing including a mix of qualitative methods with 18 in-depth interviews and focus groups with 25 participants covering all organizational levels and functions.

    Findings –

    Findings demonstrate that to re-interpret manufacturing management through the lens of Industry 5.0 (I5.0), managers need to respond to the call for a more human-centric perspective by focusing on organizational prerequisites, such as holistic understanding, inclusive organizational change, leadership practices, learning and innovation processes.

    Research limitations/implications –

    Limitations due to a single case study are compensated with rich data collected over time with the strengths of mixed methods through in-depth interviews and focus groups with participants reflecting and developing ideas jointly.

    Practical implications –

    Managers’ awareness of organizational prerequisites to promote human perspectives in all functions and at all levels in digital transformation is pivotal. Thus, proposed organizational prerequisites are presented as managers’ guidelines for future innovative manufacturing.

    Social implications –

    Findings emphasize the need for digital transformation managers to apply a human-centric perspective acknowledging how organizational changes affect the inclusion of employees, and thus challenge culture, structure, communication and trust toward I5.0.

    Originality/value –

    The study contributes to the emerging field of I5.0 by applying an interdisciplinary approach to understand the elusive phenomena of enfolding technology and humans.

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  • 197.
    Olsson, Christian
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    The automatic manufacturing processes: the technique of controlling a mobile robot2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's industry it is of mayor concern to keep the manufacturing processes as effective and flexible as possible. The usage of robots and automatic technology is a much known way to achieve the goals of rationalization. The disadvantage lays in the fact that implementation of robots is usually a very resource consuming task. However, in some circumstances a solution to this matter may be to simply implement mobile robots instead of fixed robots.

    The task of this project is to successfully control and understand the system of a mobile robot in a automatic manufacturing process.

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  • 198.
    Omicevic, Admir
    et al.
    University West, Department of Engineering Science.
    Elbing, Roger
    University West, Department of Engineering Science.
    Simulering av bultsvetsrobotar med IPS 2.0: För att utreda optimerings och balanseringsmöjlighet2010Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has been performed on a stud weld station consisting of four stud weld robots from ABB which are used in the daily production at the body plant of Saab Automobile in Trollhättan. Currently, off-line programmed robot programs from IGRIP are used in several robot cells in the body plant. IGRIP has been used for several years without having any evaluation method for how the capacity has been used in the robot cells. The limitations of IGRIP are that it cannot automatically generate collision free paths, which is very time consuming. The input of the via-points is done manually by the programmer which results in less than maximum capacity in the robot cell. These problems have triggered Saab to investigate the potential for making capacity available by using a software under development, IPS 2.0. The software is developed by FCC and has optimization and balancing functions. It can also generate collision free paths for the robots in a robot cell. One optimized path and one reference path have been created in order to evaluate the time reduction in percent. It was shown that there was potential to free up capacity in the robot cell by using IPS 2.0.Date:

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  • 199.
    Onochie, Uchenna Sylvester
    University West, Department of Engineering Science.
    Post Weld Heat Treatment of High Strength Steel Welds2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent times, the application of high strength steel (HSS) is going vast both in oil and gas, civil works, automobiles, aviation, and the military. There are numerous reasons why HSSare used in jobs, this includes their improved mechanical properties (yield strength, tensile and compressive stresses), and weight reduction. The growth in the machine manufacturing and steel treatment industries has resulted in the development and application of HSS; making manufacturing parts lighter. This advancement has provided reasonable grounds for the production of materials with better properties. There are several ways of joining HSS materials, however, a good and widely used method is welding. Welding has become the most acceptable method. Nevertheless, some notable challenges with welded HSS remain. It is acceptable to say from previous studies that the as-welded material property of the HSS is quite different and independent of the standard steel grade due to the heat signature from the weld. This can result in tensile residual stresses and low and high susceptibility to coldcracking. Solutions abound on the way to mitigate this effect and improve the mechanical properties of the welded part which include: preheating, cooling mechanism, post-weld heat treatment (PWHT), interpass temperature control, control of heat input, and application of filler metal with low hydrogen content. This study experimented on the PWHT of as-weldmetal (AWM) S690MP a high strength steel (HSS). The effect of the PWHT is considered for the AWM, mechanical and microstructural properties are compared to the AWM, then the optimum PWHT parameter is determined. The result shows much improvement with the mechanical property being more ductile at expense of hardness and the microstructure becoming more of perlite - bainite phase with an increase in the heat treatment parameter. 

  • 200.
    Ottosson, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Thermal spraying by HVAF as an environmentally friendly alternative to electrolytic hard chrome plating of piston rods2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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