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  • 51.
    Andersson, Johan
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    A computational geometry method for centrifugal compressor impellers2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Modern centrifugal compressor impeller geometry often consist of curves and surfaces with a high degree of three dimensionality. This makes the geometry of the impeller difficult to model with commercial CAD-tools. Additionally, in modern optimization processes of impellers the geometry is commonly altered, this puts high demands on the method that is used for generating the geometry. In this work a new computational geometry method for centrifugal compressor impellers is compiled. The new method is designed to be flexible and to support present day optimization processes.The new method is a compilation based upon publications regarding impeller geometry and impeller optimization. It utilizes Bezier curves and B-splines to generate geometry and supports optimization by allowing control points of the constructing curves to be relocated to change the shape of the geometry. To test the new method, a standalone application was successfully developed with the aid of the SCRUM development process. With an easy to use graphical user interface the application generates and displays a 3D model of the geometry generated with the new method.

  • 52.
    Andersson, Johan
    University West, Department of Engineering Science, Division of Production Engineering.
    Utvärdering och förbättring gällande Volvo Aeros tillämpning av metodiken praktisk problemlösning2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Volvo Aero develops, designs, manufactures and performs maintenance of engine and related components for civil and military aircrafts. The vision is to deliver world-leading transport solutions through continuous improvement and long term business deployment, which for the daily work means systematic problem solving through the methodology practical problem solving, whose origin is Toyota.

    The purpose of this thesis was to examine whether Volvo Aero’s approach of practical problem solving was simple, systematic and guided, which from Toyota’s point of view creates sound conditions for effective problem solving.

    Initially, Toyota’s attitude and behaviour towards problem solving was described from the point of view of The Toyota Way. Thereafter, a literature study on practical problem solving was completed. Furthermore, a pilot study was carried out where Volvo Aero’s approach to practical problem solving was applied to an organisational problem. The pilot study was evaluated and areas for improvements were identified where the methodology was difficult, indistinct and inadequate guided. Finally, improvements were proposed regarding Volvo Aero’s approach to practical problem solving, which was scientifically anchored to Toyota.

    • Defining and analysing the symptoms brings understanding for the causes of the problem
    • Quantifying the present condition and the expected illustrates the magnitude of the problem
    • Appears the root cause to be clear is probably the countermeasure obvious
    • A considerable approach using Plan-Do-Check-Act (PDCA) provides an effective and strong tool for continuous improvement

    The improvements were proposed with purpose to simplify Volvo Aero’s methodology and to support and guide the user, which creates sound conditions for effective problem solving and provides opportunities for daily use that foster continuous improvement.

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    praktisk problemlösning
  • 53.
    Andersson, Johanna
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Johansson, Matilda
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av standardiserat arbetssätt och kitlådor för montering av lågtrycksturbiner2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis has been executed at GKN Aerospace at the manufacturing department Low Pressure Turbine (LPT), also known as LPT. The thesis presents the creation of standardized working methods for the assembly of the LPTs, that are manufactured for the aircraft engines Leap 1B and Leap A/C. The standardized work has been compiled in Job Training Documents, also known as JTD. A kit box for the material that will be assembled has been designed for each model. Due to a nonexistent standard it has led to assembly failures and quality defects in the production. The existing assembly box has been inadequate for the operators and the controllers that pack the boxes which has led to longer assembly time. The purpose of this project has been to assure the quality of the work through creating standardized work instructions. The design of the kit box has been executed in order to organize the details of the assembly in a certain structure to facilitate for the operators and controllers. An operation description with course of action was provided and used as a basis for the design of the JTDs in order not to risk deviating from the existing method. Interviews and observations of operators and controllers have also been used for the JTDs and the design of the kit boxes. Kit boxes was reused from another department and assortment boxes was sorted and structured inside in two different sizes. These were coded with different colors, marked and fitted to the size and quantity of the material so that every piece that is being assembled has its own place. The JTDs and the kit boxes was made in two versions to adapt to the assembly of both Leap 1B and Leap A/C. The boxes were tested in the production and the JTDs was reviewed of the operators before signature was made. All of the operators were not interviewed and observed as planned because of the unplanned stops in the production. The shape of the kit box was limited because the existing boxes were reused. From the results that has been developed the goals for this thesis including creating standardized work instructions and design of a kit box to organize all the pieces has been achieved.

  • 54.
    Andersson, Marielle
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Localisation and improvement of production processes2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Company X develops innovative machines mostly for the pharmaceutical and healthcare industry, where they assemble and test the machines in their production department. When a machine is sold a certain amount of hours for mechanical and electrical assembly is offeredand Company X has seen a trend of these hours are being exceeded. Company X is then forced to bear the cost of the exceeded hours which decreases the financial profit.

    The purpose of this study is to locate activities within the production department regarding mechanical and electrical assembly processes that add no value to the final product, define the root causes of why these problems exist and find a way to improve them. The following questions this study is to answer are: 

    • How are the processes currently executed?

    • Which factors work less well in the processes?

    • What can be done to increase the performance of the processes and make them more effective?

    Data from these processes have been collected through interviews, observations and reading deviations reports. The processes are analysed to locate the greatest issues regarding the assembly process, the root causes are then found and examined. The issues selected for improvements are those that affect the employees in the production department way of working.

    A brainstorming session was executed and suggestions for improvement were presented for the employees working in the process, where they could come with inputs to form the best possible solution. The final solutions are presented more in detail and were chosen because of their impact to solve the problem and prioritised due to their simplicity to implement.

    The conclusions that were made is that if the suggested solutions are implemented it will take time for the employees to adjust to the change and it is of great importance the employees are open and devoted to making the change happen. It is also important to constantly improve the solutions and find new solutions on how to improve the employee's way of working. To accomplish this it is suggested the employees have continuous improvement meetings.

  • 55.
    Andersson, Martin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Andreasson, Kristofer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Parameterization of a B-pillar2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been performed at Benteler Engineering Service in Gothenburg in cooperation with Benteler Aluminium System Norway AS in Raufoss. Since the requirements on a product are changed several times during a product development process in the automotive industry, the desire to develop parts faster has increased. Components with complex geometries can take a large amount of time to design and when requirements on the design are changed the CAD-model has to be remade. A model with a complex geometry, which often is exposed to changes, is the B-pillar in the car. To achieve a more time efficient process for the B-pillar, an investigation was made to see if parameterization of the CAD-model could be made to save time in the development process. The result of this has shown that if the model is supposed to be changed more than three times parameterization is something that should be considered.

    Different strategies for parameterization that could support the development process of the CAD-model of a B-pillar have been compared to investigate which strategy that was best suited for this project.

    The goal to create a CAD-model of a generic B-pillar as a showpiece where parameters control the geometry and where changes of the main dimensions can be implemented faster than in a model without parameterization, has been fulfilled.

  • 56.
    Andersson, Oskar
    et al.
    University West, Department of Engineering Science.
    Clasborn, Oliver
    University West, Department of Engineering Science.
    Förstudie och design av transportutrustning för rymdmunstycke till Prometheus raketmotor2024Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This is a thesis initiated by GKN Aerospace with the aim of developing transport equipment for a nozzle for the Prometheus rocket engine. GKN is about to start production of the nozzle and needs packaging that meets the cleanliness requirements specified by the customer. Currently, GKN does not have packaging that meets these requirements and, therefore, needs to develop a new packaging solution.

    A packaging concept is developed through a concept development process described in Ulrich and Eppinger's book "Product Design and Development”. In this process, customer requirements are identified and compiled into target specifications that the concept should fulfill. Solutions are developed based on these target specifications, and several different concepts are generated, each aiming to meet the customer's needs and requirements.

    A final concept is chosen, specified, and described in more detail. A supplier is contacted during the project, offering expertise in the field. The supplier also provides their version of the packaging and a cost estimate. A rough life cycle inventory is conducted to compile the carbon dioxide emissions of the packaging to present the environmental consequences.

    The developed concepts address all the issues presented and offer the company several different solutions to choose from

  • 57.
    Andreassen, Håkon
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Fallstudie av tidsförluster inom kemisk industri2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been carried out with the purpose of streamlining production at Nouryons EMU factory in Stenungsund. The goal has been to map and identify the root causes to nonvalue-creating time in the production. The work began with a literature study where relevant theory and information was taken from books, articles and websites. Subsequently, a case study was conducted which is partly based on observations and unstructured interviews, but also on data from Nouryons internal reporting system OAM portal. The work has been able to establish that there are five categories that together account for 54% of the lost production time in the factory. An analysis of these revealed, however, that data should be treated with some caution. During the work, it has been established that 12% of the events under the category Quality analysis in reactor stage two are probably incorrectly categorized. A suggestion for improvement is for Nouryon to map these events, which can possibly be turned into two separate categories. Here, this project can form the basis forfurther development of the OAM portal.

  • 58.
    Anselmby, Ellen
    University West, Department of Engineering Science.
    Radio Remote Control in Industry 4.02022Independent thesis Basic level (professional degree), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    After a number of industrial revolutions, the industry is facing a new revolution, the 4th industrial revolution, also called Industry 4.0. The revolution referring to emerging technologies such as Internet of Things, Big data, Digital Twins, Cyber-physical System among others.

    Tele-Radio i Lysekil AB is a company that is develop, produce and distribute radio remote controls. These remote controls are wireless and is used in an industrial environment. Operators that use this as a tool can stand from a safe distance, observe the action, and control the process with the remote.

    This thesis project focuses on researching how radio remote control system can be utilised to create a safe and flexible workplace in an Industry 4.0 environment. How should companies, developing products adapt and integrate to the industry that is implementing Industry 4.0 to their process, how will the workplace and organisation change?

    The Industry 4.0 will change the way of working. The need for operators to adjust and develop their skills and knowledge to properly manage the new digital solutions and technology will likely be the source of human resistance.

    The need for a radio-controlled remote control system will continue to exist. In a situation where large amounts of data are available, and the operator is carrying a device that allows him or her to manage the environment, the need and capacity to respond to.

  • 59.
    Aranke, Omkar
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Algenaid, Wael
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Awe, Samuel
    R and D Department, Automotive Components Floby AB, Floby, 52151, Sweden.
    Joshi, Shrikant V.
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Coatings for automotive gray cast iron brake discs: A review2019In: Coatings, ISSN 2079-6412, Vol. 9, no 9, article id 552Article in journal (Refereed)
    Abstract [en]

    Gray cast iron (GCI) is a popular automotive brake disc material by virtue of its high melting point as well as excellent heat storage and damping capability. GCI is also attractive because of its good castability and machinability, combined with its cost-effectiveness. Although several lightweight alloys have been explored as alternatives in an attempt to achieve weight reduction, their widespread use has been limited by low melting point and high inherent costs. Therefore, GCI is still the preferred material for brake discs due to its robust performance. However, poor corrosion resistance and excessive wear of brake disc material during service continue to be areas of concern, with the latter leading to brake emissions in the form of dust and particulate matter that have adverse effects on human health. With the exhaust emission norms becoming increasingly stringent, it is important to address the problem of brake disc wear without compromising the braking performance of the material. Surface treatment of GCI brake discs in the form of a suitable coating represents a promising solution to this problem. This paper reviews the different coating technologies and materials that have been traditionally used and examines the prospects of some emergent thermal spray technologies, along with the industrial implications of adopting them for brake disc applications. © 2019 by the authors.

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    fulltext
  • 60.
    Arbat, Akshay
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Thermal spray coatings on additive manufacturing parts: Coating deposition and investigation2021Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Additive manufacturing (AM) is gaining popularity due to the increased demands for the production of complex geometries and difficult-to-machine components. The increasing trend of AM focuses more on high-temperature applications in the field of aerospace, automotive, power generation, etc. In high-temperature applications, the material often needs to be resistant to oxidation and corrosion. Alloy 718 is a promising material because of its better properties at elevated temperatures. Recently alloy 718 based parts have been manufactured by the electron beam powder bed fusion (EBPBF) process. Different post-processes such as shot peening (SP) and hot isostatic pressing (HIP) were used to improve the properties of the AM-built samples. As an alternative method to post-processing, NiCoCrAlY coating was thermal sprayed on the AM-built samples.

    The present study explores the effect of the different processing methods on the mechanical and functional properties of the coatings . Post-processes help reduce the roughness of AM components due to the peening effect during SP and temperature and pressure during HIP. The shot peening was responsible for increasing the hardness near the coating-substrate interface while HIP reduces the hardness due to grain coarsening and dissolution of strengthening phases. The NiCoCrAlY coating was deposited on the sample by a high-velocity air fuel process. Coated AP, SP3 and HIP samples showed better adhesion strength because of mechanical interlocking between coating and substrate. The coating acts as a protective layer by forming oxide scale (Cr and Al oxides) and helps to protect the substrate from corrosion and oxidation. The shot peening was responsible for reducing the erosion rate in uncoated samples, while the coated sample showed similar behavior.

    The present study explores the effect of post-process on the coating microstructure and other properties. The AM-produced sample does not require post processes before spraying a coating. Thermal spraying on AM parts is beneficial for improving properties. 

  • 61.
    Arghavan Shahlaei, Charlotte
    et al.
    University West, School of Business, Economics and IT, Divison of Informatics.
    Kazan, Erol
    IT University of Copenhagen, Copenhagen (DNK).
    Digitizing Products towards Platforms: the Case of Vehicle Motion System2020In: Making Digital Inclusive: Blending the Local and the Global, Association for Information Systems, 2020, article id 2557Conference paper (Other academic)
    Abstract [en]

    The development of digital product platforms is a prevailing trend in many industries. As firms incorporate digital technologies into established product categories, they need to manage tensions on multiple organizational layers including strategy, technology and structure. Recent findings suggest that tensions are most likely to be managed by creating resource and coordination flexibility. This paper reports a longitudinal case study of developing a digital product platform. By drawing on organizational ambidexterity theory, we identify four mechanisms—re-scripting, centralizing-re-directing and decoupling—through which the firm creates resource and coordination flexibility. The resulting resource and coordination flexibility in turn lead to the transformation of the firm’s strategy, technology and internal structure. The contribution of this study is in adopting an internal perspective and a bottom-up approach which help to theorize the evolution of digitized products into digital product platforms in an emergent way.

  • 62.
    Arvidsson, Jakob
    et al.
    University West, Department of Engineering Science.
    Svensson, Pontus
    University West, Department of Engineering Science.
    Analys av varmsprickor i PBF-LB additivt tillverkad Alloy 718 genom varestraint metoden2023Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Alloy 718 is a well-used superalloy within the aerospace industry and other applications where heat resistance is needed. The interest in making more difficult geometries has existed for a long time, and additive manufacturing of the material facilitates that request. When manufacturing with the powder bed fusion laser bed method the size is very limited by the baseplate that is used, which is usually small. Hence, a joining between additive and manufactured Alloy 718 is an alternative to obtain a larger product. The problem that has been discovered is that when the welding process takes place cracks occur within the heat affected zone (HAZ), that’s why a good merging of the alloy is of great interest.

    The goal of this study is to analyse laser welded Alloy 718 manufactured by the PBF-LB method and identify its susceptibility towards cracking, then compare these with previous research, where the same material and manufacturing method was tested with TIG welding. To see which welding process affects the HAZ the least negatively and then draw a conclusion.

    The conclusion was found that the concentrated beam from the laser affects the material in the HAZ less than TIG welding electric charged arc.

    This study provides a new insight into the material’s reaction the heat through joining and helps in decision-making about which welding process should be appropriate for joining the material.

  • 63.
    Augustsson, Nathalie
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Löfström, Helena
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of the virtual training softwares SeQualia and Vizendo2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The automotive industry is constantly developing and manufacturing industry is facing modernisation and need for increased efficiency which implies that the automotive industry is facing changes for assembly training. To minimise quality errors and save time computerbased training virtual training can be used to practice on product knowledge, variants and sequences. Currently in traditional training in automotive industries, the operators practice on psychical products. The purpose of this bachelor thesis is to obtain knowledge of the effects of virtual training with cycle times longer than five minutes by evaluate the virtual training methods at Scania in Södertälje, Sweden. To achieve the purpose of the thesis the objective is to create a basis of the advantages and disadvantages. Scania is part of the Volkswagen Group and is a world leading supplier in the automotive industry which develops custom made and high-quality products with short lead times. Scania’s core products are heavy trucks, buses and engines for marine and industrial applications. Scania has 46 000 employees in 100 countries. Today Scania use standardised work and Job Instructions Training tools for learning the assembling processes which could be time consuming, ineffective and resource-intensive. Therefore, Scania’s vision with virtual training is to shorten the learning time on-line by implementing virtual training to practice off-line. The main objectives are to reduce the time for training simultaneously as the product quality increases. To obtain reliable information to reach the purpose a qualitative approach has been used in the study. To obtain primary data the methods have been semi-structured interviews, observation and questionnaires that have been performed and literature studies have been used to collect secondary data to obtain a broad knowledge of the subject. Through this the bachelor thesis resulted in recommendations that will contribute to Scania’s decision of future work with virtual training. The recommendations have been based on the previous accomplished studies, results and obtained comments which together were connected in the discussion and by the recommendations the authors believe that Scania can use virtual training with success.   

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    fulltext
  • 64.
    Azar, Amin S.
    et al.
    SINTEF Mat & Chem, Oslo, Norway.
    Svensson, Lars-Erik
    University West, Department of Engineering Science, Division of Production Engineering.
    Nyhus, Bård
    SINTEF Mat & Chem, Oslo, Norway.
    Effect of crystal orientation and texture on fatigue crack evolution in high strength steel welds2015In: International Journal of Fatigue, ISSN 0142-1123, E-ISSN 1879-3452, Vol. 77, p. 95-104Article in journal (Refereed)
    Abstract [en]

    In the present study, electron backscattered diffraction is used to analyze the fatigue crack evolution in a high strength steel weld that was loaded cyclically in the plastic regime. Three prominent regions of a fatigue crack are investigated separately: crack tip, crack trajectory and crack initiation. Taylor and Schmid factors are mapped with respect to the defined loading matrix. Possible effective mechanisms are proposed based on the local plasticity properties like lattice rotation and misorientation. The analyses of the crack tip and trajectory regions show that although the critical resolved shear stresses in some regions are low, small deformation resistance of these regions can compromise the dislocation immobility and cause local fracture. It is shown that if the crack grows transgranularly, at least one side of the crack may show low lattice rotation or strain equivalent values, which indicates the relaxation of elastic stresses after fracture. The crack initiation is determined to be dominantly controlled by transcrystalline mechanism of initiation that takes place under plastic loading conditions. It is also shown that the secondary < 123 >11 (1) over bar type of slip systems were the most activated under such loading conditions. (C) 2015 Elsevier Ltd. All rights reserved.

  • 65.
    Aziz, Jamal
    University West, Department of Engineering Science.
    Assessing the recycling of cathodes in Physical Vapor Deposition systems to promote circularity and sustainability2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Climate change, because of greenhouse gas (GHG) emissions from human activities, has become a critical issue as it is affecting our environment. According to the Paris Agreement, an international agreement on reducing GHG emissions and addressing climate change, it was agreed that global warming should be kept below 2°C above the preindustrial level and preferably at 1.5°C. To be able to reach this goal, countries and non-state entities, such as companies and individuals, are making efforts to reduce GHG emissions. In this respect, as with many other companies, Seco Tools AB has a goal to reduce 50% of its GHG emissions by 2030 and reach net zero emissions by 2050.

    This study was conducted with the aim of determining and understanding the impact of GHG emissions in physical vapor deposition (PVD) coating production. In addition, to potentially increase the use of materials and reduce GHG emissions, a study was done on the effect of recycling cathode (target) materials on the process, microstructure, and properties of TiAlN coating. The analysis was performed to determine how much CO2 emissions can be avoided by recycling cathode materials.

    The boundaries selected for the estimation of GHG emissions are the use of electrical energy, water, process gases, and cathode materials during the process. The present study shows that the PVD coating process emits about 13.76 kg CO2 to produce a standard batch of TiAlN coating. The shares of emissions from cathode materials, electrical energy, water, and process gases are 76%, 17%, 6%, and 1%, respectively.

    The effect of recycled materials on the process, microstructure, and properties of TiAlN coatings produced by cathodic arc deposition was investigated. The coatings were grown with varying chemical compositions from recycled cathodes on cemented carbide substrates at different substrate bias voltages (-25 V, -45 V, and -65 V). The coating thickness, adhesion strength, microstructure, macroparticle presence, phase formation, and residual stress of coatings were investigated and compared with those produced with virgin cathodes, and the results were found to be similar. The coatings showed excellent adhesion strength, and the thicknesses ranged from 1.9 to 3.2µm. The cross-sectional micrographs revealed that the coatings exhibit dense columnar microstructures and the presence of microparticles. Applying a higher bias voltage resulted in coatings with fewer microparticles and increased compressive residual stresses. Phase analysis by X-ray diffraction indicated that a single cubic phase was formed in the coatings. 

    The analysis of the impact of cathode recycling on GHG emissions reduction revealed that a proper recycling procedure can potentially reduce 9.70 kgCO2 per batch.

  • 66.
    Babu, Challa
    et al.
    Department of EEE, Siddartha Institute of Science and Technology, Puttur, AP (IND).
    Immanuel, A.
    Department of EEE, Audisankara College of Engineering and Technology, Gudur, AP (IND).
    Jyotheeswara Reddy, K.
    School of EEE, REVA University, Bangalore, Karnataka (IND).
    Kumar, K.
    Department of EEE, SV College of Engineering, Tirupathi, AP (IND).
    Ramasamy, Sudha
    University West, Department of Engineering Science, Division of Production Systems.
    Venkateswarlu, S.
    School of Electrical Engineering, VIT University, Vellore (IND).
    Performance analysis of flat plate hybrid PV/thermal configurations2022In: AIP Conference Proceedings, American Institute of Physics (AIP), 2022, Vol. 2461, article id 060007Conference paper (Refereed)
    Abstract [en]

    In the recent times many hybrid renewable energy sources are developed. In that, hybrid PV/Thermal gains the more attention than other hybrid sources. In the present work, made a performance analysis of different PV/Thermal configurations. The flat plate configurations have the more feasibility for the domestic applications than the concentrated type. In this paper, liquid, air, nano fluid, phase change material and Thermoelectric generator type configurations are presented. The performance analysis of all configurations done with energy output generation and efficiency of the system. 

  • 67.
    Bachmann, Gabriel
    et al.
    University West, Department of Engineering Science.
    Göbel, Niklas
    University West, Department of Engineering Science.
    Evaluation of requirements for measurement technology in mobile hydrogen applications including associated infrastructure with the aim of creating recommendations for measuring devices2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this master thesis is to point out where pressure and temperature measuring devices can be implemented in the hydrogen production, supply chain, storage system, refuelling station and in a hydrogen vehicle. For this reason, a basic knowledge for hydrogen as a chemical element and energy carrier in a vehicle has to be gained. Moreover, production methods, storage systems and the supply chain of hydrogen are described.

    It has been shown that in order to ensure safe and stable processes it is indispensable to measure pressure and temperature in the entire hydrogen chain from the production right through to the energy conversion in a vehicle. On the basis of these results, the requirements and type approval processes of measuring devices in mobile hydrogen applications including associated refuelling stations are analysedto ensure a safe and reliable market entry for manufacturers. Special attention will be paid to possible challenges while measuring state sizes of hydrogen.

    It has turned out that the European main standard EC79/2009 that regulates requirements and type approvals of components in mobile hydrogen applications will be repealed in July 2022. To find an adequate alternate standard, the American regulation HGV 3.1 is analysed in regards to commonalities and differences to EC79/2009. The result of the comparison is that in terms of type approvals for components in compressed gaseous mobile hydrogen applications HGV 3.1 scopes most of the relevant contents of EC79/2009 and can therefore be used as an alternative. However, when it comes to components for liquid hydrogen contact in mobile hydrogen applications there are no alternatives to the European standard. For this reason, until the gap is closed by a new international standard, manufacturers for components with liquid hydrogen contact have to refer to certain requirements of EC79/2009 but approve products according to valid regulations like HGV 3.1.

    Finally, the analysis of requirements and type approvals for components used in refuelling stations according to ISO 19880-1 showed that close arrangements between customer and manufacturer is indispensable to ensure a smooth process.

  • 68.
    Backelin, Christoffer
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Experimental study of trepanning process with nickel-base superalloy sheet, using CO2 laser.2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis experimentally investigates the defect generated at the start and stop zone when trepanning, using CO 2 laser and the nickel-base superalloy Hastelloy X. The project has been performed at Siemens Industrial Turbomachinery AB (SIT) in Trollhättan. Experiments which investigates the effect of altering entrance radius, exit radius (withdrawal) and nozzle distance have been performed. Samples were created by using a Trumpf 2D-laser machine and they were prepared for evaluation by grinding, polishing and etching. The Sample were then evaluated and measured by using an optic microscope. Experiments have been planned according to the method, design of experiments (DOE).

    By using the programme Minitab, regression analysis and empirical models were created which describes the effect of the tested parameters. The results show that it is possible to decrease the start and stop defects by altering of the process parameters.

  • 69.
    Bader, Mirjam
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Nuur, Ilham
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    En logistikstudie med fokus på faktorer inför implementering av produktionsflödessimulering: Siemens Industrial Turbomachinery AB2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During a ten-week period, in the spring term of 2020, a thesis project was carried out with the aim of creating an understanding of how production flow simulation can be used as a sustainable activity to plan production and achieve more efficient planning at Siemens Industrial Turbomachinery AB in Trollhättan. The aim of the study was to examine the differences between planned production times in the enterprise resource planning system and the reported production time and to propose a flow simulation model that can be reused to achieve a more balanced production flow.

    The problem situation that formed the basis of the study was that there is uncertainty as to whether the reported time corresponds to the times planned in the enterprise resource planning system. The company has also lifted aspects such as long waiting times, high buffer and storage levels between operations, long transport distances and a large number of work in progress (WIP). With a more accurate production planning, these problem areas can be highlighted and with time, reduce waiting times and WIP.

    The data that formed the basis for the thesis work was provided by the company and production times and logistical aspects were calculated and analyzes. After the analyzes, results showed that there are differences between the planned and the reported production times. Thus, it can be concluded that regular follow-up of the reported data should be initiated at the company to improve understanding of why there are discrepancies between planned and reported times, and to work towards reducing the gap between planned and reporting production times. The results also showed more trends regarding production times and logistics aspects, such as increased production times during the year, a bottleneck in production was discovered and how much of the total lead time that is value-creating in the internal process was highlighted.

    Based on the results that focused on outlining the production flow, a conceptual simulation model was built that visualizes the production, which is a starting point for further development and use of production flow simulations. It was concluded that the data collection aspects and its analysis were of large importance for preparation of building the model. It is of great value to have good insight into the production flow of the company and the conclusion stresses the importance of a detailed study of the production flow and to understand the production data before deciding on whether a simulation model should be built and the scoop of that model.

  • 70.
    Baga, Moustafa
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Demeter, Janos
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Undersökning av hårdhet på pulverbäddtillverkad superlegering 247 LC2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Alloy 247 LC is a material that is used in manufacturing for making gas turbine blades and is made of nickel. Due to that the material in the blade has a high strength at high temperatures and a melting point higher than 1200 °C, is the blade can be used in the warmest/hottest sections of jet engines and turbines. The efficaciousness of the motors depends on the temperatures, and the higher temperature the more efficiency. This induces a cut/saving of fuel. Nowadays the blades are made of casting which brings a big effort in both time, labor, and material. To make the production of Alloy 247 LC more effective the research is in progress and focuses on how the product can be performed with different methods. One of these methods is called additive manufacturing which is also called 3D print. This method includes laser powder bed fusion (L-PBF) and implies laser-based melting in powder bed. Laser powder bed fusion is a process that simplifies the production of very complex shapes of blades which can be problematic during the manufacturing in casting. The most important characteristics of Alloy 247 LC is the strength and hardness. Hence, it is important that these features are preserved also during laser powder bed fusion. The purpose of this study is to measure the hardness at Alloy 247 LC which is manufactured through laser powder bed fusion (L-PBF) in additive manufacturing and subsequently compare the result of hardness values with the given hardness values that the casting has. This to investigate if these features are preserved through laser powder bed fusion (L-PBF) due to that the most important characteristics of Alloy 247 LC are strength and severity. We used 36 test cubes with the dimensions of 15x15x15 mm. The cubes were produced with/through laser powder bed fusion with varying process parameters on power and speed to and arrive at the most suitable for the hardness of the material. The cubes were divided into three pieces each which implicated that we had 108 pieces for the test. Thereafter the result from the hardness values was compared with the hardness values from the casting. To get a deeper understanding of the results of hardness values, all of the pieces from the test were analyzed with the help of optical microscope. Further four pieces from the test were chosen and also observed in a scanning electron microscope in order to examine the microstructure. The conclusion in the study was that laser powder bed fusion (L-PBF) can be a suitable method if used with the right process parameters.

  • 71.
    Bahbou, M. Fouzi
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    A study of the adhesion strength of plasma sprayed coatings2007Doctoral thesis, comprehensive summary (Other academic)
  • 72.
    Bahbou, M. Fouzi
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    On-Line measurement of plasma-sprayed ni-particles during impact on a ti-surface: influence of surface oxidation2007In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 16, no 6, p. 506-511Article in journal (Refereed)
    Abstract [en]

    The objective of this study was to analyze the impact of plasma-sprayed Ni5%Al particles on polished and grit-blasted Ti6Al4V samples under oxidized and nonoxidized conditions. For this purpose, measurements of thermal radiation and velocity of individual plasma-sprayed particles were carried out. From the thermal radiation at impact, splat diameter during flattening and temperature evolution during cooling were evaluated. Characteristic parameters related to the quality of contact between the splat and the substrate were retrieved. The flattening speed was introduced to characterize wetting, while the cooling rate was used to characterize solidification. The idea was to get a signature of particle impact for a given surface roughness and oxidation state by identifying parameters which strongly affect the splat behavior. Sieved Ni5%Al powder in a narrow range (+65 −75 μm) was sprayed on four sets of titanium alloy surfaces, consisting of polished and grit-blasted samples, one set had a nonoxidized surface and the other one was oxidized in an oven at 600 °C for two hours. Resulting splats after impact were characterized by scanning electron microscopy, the splats on oxidized surface showed pores in their core and detached fingers at the periphery. The cooling rate and flattening degree significantly increased on the oxidized smooth surface compared to the nonoxidized one. This trend was not found in grit-blasted surfaces, which implies that impact phenomena are different on grit-blasted surfaces than on smooth surfaces thus further work is needed.

  • 73.
    Bahbou, M. Fouzi
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Relationship between surface topgraphy parameters and adhesion strength for plasma spraying2005In: ITSC 2005: Thermal Spray connects: Explore its surfacing potential!, The Material Information Society , 2005, p. 1027-1031Conference paper (Refereed)
    Abstract [en]

    To achieve sufficient adhesion strength within thermal spraying, the surface to be coated has to be modified. Grit blasting is the most common way to generate a clean and roughened surface. The bonding mechanism between the grit-blasted substrate and the coating is assumed to be due to mechanical anchoring, why an optimal surface roughness is essential. The surface roughness is usually evaluated using Ra which cannot fully characterize the complex nature of the chaotic substrate topography. This study was performed in order to evaluate if Ra can be replaced by other surface characteristic parameters such us R.q, Rpk, Rpv, Rk…with higher correlation to adhesion strength. Average roughness was measured by a perthometer and with white light interferometry to get 3D images of the surface topography. Disc shaped substrate samples of Ti6Al4V (AMS 4928) were grit blasted with aluminium oxide grit and plasma sprayed with a Ni5%Al coating. Adhesion strength was determined according to the ASTM C633 standard. The correlation between a number of different surface-parameters and adhesion strength were evaluated and compared with Ra.

  • 74.
    Bahbou, M. Fouzi
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Two-step grit blasting for enhanced adhesion of thermal spray coatings2004In: Surface modification technologies XVIII: proceedings of the eighteenth international conference on surface modification technologies held in Dijon, France November 15-17, 2004, 2004, p. 23-27Conference paper (Refereed)
  • 75.
    Bahbou, M. Fouzi
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Nylén, Per
    University West, Department of Engineering Science, Division of Production Engineering.
    Barbezat, G.
    Sulzer Metco, Wohlen, Switzerland .
    A parameter study of the Protal® Process to optimise the adhesion of Ni5Al Coatings2004In: Thermal Spray 2004 : Advances in technology and applications: Proceedings of the International Thermal Spray Conference 10-12 May 2004, Osaka, Japan Thermal Spray 2004, 2004, p. 898-902Conference paper (Refereed)
    Abstract [en]

    The Protal process combines surface preparation using a laser and thermal spraying in one production step. The laser preparation is based on a photomechanical reaction induced by the interaction between a laser of high instantaneous power and a polluted surface. The mechanism of bonding and the coating-substrate interface are then changed in comparison with grit blasting resulting in a significantly reduced substrate roughness. This study is aimed at finding the optimal Protal process parameters for the coating adhesion of a Ni5%Al sprayed on Ti6Al4V and IN718 alloys. The parameters investigated are laser beam intensity, the time delay between the laser impact and the spray impact, powder feed rate, substrate roughness and temperature. A test plan including these parameters is analysed by means of a fractional factorial design of experiment method. The adhesions of the coatings are measured using the ASTM C633 standard test. Data are analysed by a multiple linear regression model using a least squares fit. In addition, the coating/substrate interface is examined by optical and electron scanning microscopy (SEM) techniques as well as by Auger electron spectroscopy. Substrate roughness, substrate temperature and laser intensity are all shown to have a negative correlation with adhesion strength within the investigated range. Areas of diffusion are noticed at the coating/substrate interface.

  • 76.
    Bahbou, M. Fouzi
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Nylén, Per
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Wigren, J.
    Volvo Aero, Trollhättan.
    Effect of grit blasting and spraying angle on the adhesion strength of a plasma-sprayed coating2004In: Journal of thermal spray technology (Print), ISSN 1059-9630, E-ISSN 1544-1016, Vol. 13, no 4, p. 508-514Article in journal (Refereed)
  • 77.
    Bahtiri, Besnik
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Olsson, Philip
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Automatisering av lågvolymsproduktion: en fallstudie2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A common perception is that it can be difficult to reach a profit margin when automating low volume production. To reach a profit margin, it is required to have a high utilisation rate while still producing profitable products. Vänersborgs Svets & Mekaniska Verkstad manufactures a lot of different low volume products and has recently invested in a robot welding machine. Vänersborgs Svets & Mekaniska Verkstad wants to explore if it will be cost effective to automate four of their low volume products. The robot welding machine has yet to be delivered, hence all calculations will be theoretical.

    The results show that the total cost for the chosen products will be lower if automated, compared to their current method. The cost per part has also been reduced.

    Thus, it is possible for Vänersborgs Svets & Mekaniska Verkstad to increase their cost efficiency by automating the chosen products. The low utilisation rate makes it possible for the company to expand by entering one or more high volume contracts, alternatively entering low volume contracts where the OEM is responsible for the fixture- and programming costs. Vänersborgs Svets & Mekaniska Verkstad should explore the possibility of automating other parts of their products as well.

  • 78.
    Balachandramurthi, Arun Ramanathan
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Jaladurgam, Nitesj Raj
    Chalmers University of Technology, Department of Physics, Gothenburg, SE-412 96, Sweden.
    Kumara, Chamara
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Hansson, Tomas
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. GKN Aerospace Sweden AB, Trollhättan, SE-461 38, Sweden.
    Moverare, Johan
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. Linköping University, Department of Management and Engineering, Linköping, SE 581 83, Sweden.
    Gårdstam, Johannes
    Qunitus Technologies AB, Västerås, SE-721 66, Sweden.
    Pederson, Robert
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    On the microstructure of laser beam powder bed fusion alloy 718 and its influence on the low cycle fatigue behaviour2020In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 13, no 22, article id 5198Article in journal (Refereed)
    Abstract [en]

    Additive manufacturing of Alloy 718 has become a popular subject of research in recent years. Understanding the process-microstructure-property relationship of additively manufactured Alloy 718 is crucial for maturing the technology to manufacture critical components. Fatigue behaviour is a key mechanical property that is required in applications such as gas turbines. Therefore, in the present work, low cycle fatigue behaviour of Alloy 718 manufactured by laser beam powder bed fusion process has been investigated. The material was tested in as-built condition as well as after two different thermal post-treatments. Three orientations with respect to the building direction were tested to evaluate the anisotropy. Testing was performed at room temperature under controlled amplitudes of strain. It was found that defects, inclusions, strengthening precipitates, and Young’s modulus influence the fatigue behaviour under strain-controlled conditions. The strengthening precipitates affected the deformation mechanism as well as the cycle-dependent hardening/softening behaviour. The defects and the inclusions had a detrimental effect on fatigue life. The presence of Laves phase in LB-PBF Alloy 718 did not have a detrimental effect on fatigue life. Young’s modulus was anisotropic and it contributed to the anisotropy in strain-life relationship. Pseudo-elastic stress vs. fatigue life approach could be used to handle the modulus-induced anisotropy in the strain-life relationship. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

  • 79.
    Bari, Mahdi
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    A finite element study of shell and solid element performance in crash-box simulations2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis comprehends a series of nonlinear numerical studies with the finite element software's LS-Dyna and Impetus AFEA. The main focus lies on a comparative crash analysis of an aluminium beam profile which the company Sapa technology has used during their crash analysis.

    The aluminium profile has the characteristic of having different thickness over span ratios within the profile. This characteristic provided the opportunity to conduct a performance investigation of shell and solid elements with finite element analysis.

    Numerical comparisons were made between shell and solid elements where measurable parameters such as internal energy, simulation times, buckling patterns and material failures were compared to physical tests conducted prior to this thesis by Sapa technology.

    The performance investigation of shell and solid elements was initiated by creating models of the aluminium profile for general visualization and to facilitate the meshing of surfaces. The meshing procedure was considered to be an important factor of the analysis. The mesh quality and element orientations were carefully monitored in order to achieve acceptable results when the models were compared to physical tests.

    Preliminary simulations were further conducted in order to obtain a clear understanding of software parameters when performing crash simulations in LS-Dyna and Impetus AFEA. The investigated parameters were element formulations and material models. A general parameter understanding facilitated in the selection of parameters for actual simulations, where material failure and damage models were used.

    In conclusion, LS-Dyna was observed to provide a bigger internal energy absorption during the crushing of the beam with longer simulation times for solid elements when compared to shell elements. Impetus AFEA did on the other hand provide results close to physical test data with acceptable simulation times when compared to physical tests.

    The result difference obtained from the FE-software's in relation to physical crash experiments were considered to be varied but did indicate that shell elements were efficient enough for the specific profile during simulations with LS-Dyna. Impetus AFEA proved that the same time to be numerically efficient for energy approximations with solid elements refined with the third polynomial.

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  • 80.
    Basaran, Hüsnücan
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    El Labaki, Jonathan
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Byggprojektledning: att strukturera upp projektledares tillvägagångssätt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The bachelor's thesis of 15 credits was carried out in Vara municipality after the property manager stated a need. The task was to standardize the project managers' approach in terms of management and structure, and to improve the possibility of new recruitments and takeovers of existing projects. With the help of interviews, it was identified that the project managers worked in different ways without tools to support structuring and managing their projects.

    In order to be able to answer how the problem image could be sorted out, the writers designed a content for a manual that the project managers could use. By following the contents of the manual, the project managers are expected to be able to more easily manage and structure their projects. As a result of a standardized work method, new recruitments and takeover of projects are also expected to be simplified.

    The introductory chapter of the bachelor's thesis describes how the background to the work looked, as well as the purpose, goal and delimitation.

    The second chapter describes the writers' method for designing the work that followed a scientific starting point.

    The third chapter consists of the writers' theory sections that were needed to create an understanding of how the actual construction process and the project management process could look. This chapter was used as a knowledge base to be able to make decisions about the contents of the manual.

    With the help of interviews and meetings at the municipality, a current situation analysis was formed, which is presented in chapter four. The current situation analysis was used as a basis for designing the contents of the manual.

    In the fifth chapter, the contents of the manual are described using a presented result as well as discussion and analysis of why the content was necessary for the project managers to follow.

    Finally, in the sixth chapter, a conclusion is drawn about how the purpose of the degree project should be fulfilled and a future recommendation for continued work in the subject area.

  • 81.
    Bates, William
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Casting repair and Surface Modification of Aluminum Alloys using Friction Stir Processing (FSP)2021Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates using friction stir welding to repair common surface defects found in aluminum-silicon sand castings. Wherein, the effect of welding parameters: weld RPM, weld speed, and number of weld passes, were evaluated using hardness, porosity density, welding temperature, microstructure refinement as metrics. Therefrom, the results strongly suggest friction stir welding: reduces porosity size, reduces porosity density in a specific area, increases average hardness, improves hardness uniformity, increases surface roughness, redistributes microstructure features in a manner that theoretically improves strength, and maintains a welding temperature less than 660 degrees Celsius.

  • 82.
    Beaubert, F.
    et al.
    TEMPO, UVHC, Campus Mont Houy, 59313 Valenciennes Cedex 9, France.
    Pálsson, H.
    University of Iceland, Sæmundargötu 2, Reykjavík 101, Iceland.
    Lalot, S.
    EMPO, UVHC, Campus Mont Houy, Valenciennes Cedex 9, France.
    Choquet, Isabelle
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Bauduin, H.
    EMPO, UVHC, Campus Mont Houy, Valenciennes Cedex 9, France.
    Fundamental mode of freely decaying laminar swirling flows2016In: Applied Mathematical Modelling, ISSN 0307-904X, E-ISSN 1872-8480, Vol. 40, no 13-14, p. 6218-6233Article in journal (Refereed)
    Abstract [en]

    Abstract A detailed study of a swirling flow in a tube is presented in the first part of the paper. A simplified analytical solution of the governing equations indicates specific modes of the tangential velocity and that the decay of the swirl effect is exponential. The problem is then solved in three dimensions using computational fluid dynamics (CFD) and a comparison with analytical expressions shows that the CFD code is reliable in terms of accuracy. The CFD results confirm that a fundamental swirling mode is reached within a short distance from the inlet. The torque swirl number is introduced to physically estimate the intensity of the swirl. A companion value is given: it is the average deviation.

  • 83.
    Bekele, Firanbon Zeleke
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Explaining the Impact of Chatter on Surface Roughness2021Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a machining operation, self-excited vibration called chatter resulting from the interaction of a workpiece, a tool, and a machine is limiting manufacturers in selecting cutting process parameters that give the desired surface finish at a higher material removal rate. Thisresearch paper aimed to add some control over its impact on surface roughness by establishing a simulation model of the surface topography. The simulation was done by incorporating time-domain simulation of the cutting process based on the theory of machine and Z-buffer geometrical modelling technique. Z-buffer modelling technique applied by representing the workpiece as a Z-buffer model and by discretely dividing the cutting-edge displacement along the tool path. The main purpose of the time domain simulation was to get information about the tool displacement relative to the workpiece along the tool path to conduct z-buffering.

    The influence of chatter on surface roughness was investigated on floor end milling by selecting a different combination of depth of cut and spindle speed keeping the feed rate constant. The resulting surface roughness of the simulated surface was analysed and described quantitatively by taking the arithmetic mean height (Sa) and maximum height (Sz) as a candidate for a real surface roughness measurement. The simulated surface model results were compared to the experiment. The result obtained shows that surface simulation has the potential to predict chatter and surface roughness that can be used for surface finish control when selecting cutting process parameters.

  • 84.
    Benages Vila, Daniel
    University West, Department of Engineering Science.
    Process parameter optimization for Laser Metal Deposition using Hastelloy X blown powder2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Hastelloy X (HX) is a nickel-base superalloy with strong resistance to oxidation and stress corrosion cracking combined with high temperature strength, these characteristics make it perfect for gas turbine engine components. The lack of machinability of this material makes laser metal deposition (LMD) suitable for the production and/or repair of components of HX, which uses a laser beam to melt the powder particles. Moreover, LMD has the features and versatility to implement this technology in the industry.

    The objective is to analyse a design of experiment covering a range of process parameters (laser power, scanning speed and powder feed rate) to find a suitable parameter set for using LMDp with Hastelloy X. Properties of interest are build rate, microstructure, and minimum defects such as pores and cracks. Based on a design of experiments, 11 samples with 4 walls of different layers (15 layers, 5 layers, 3 layers and 1 layer) were printed. Then the samples were analysed using a light optical microscope and a hardness test along the build section.

    The results showed that each parameter has a different effect on the geometry accuracy. On the other hand, only scanning speed had a directly proportional effect on the microhardness. However, the powder feed affected the distance where the highest hardness point was found. Regarding the defects such as cracks and pores, any parameter had an important role, all the pores where evenly distributed on the laterals of the build. Moreover, cracks caused by lack of fusion where only found on one sample. Concerning the microstructure, all the samples presented the same evolution, the lower layers microstructure consists of fine columnar dendrites with an equiaxed morphology growing perpendicularly to the substrate in vertical direction, whereas the top layers consist of coarser columnar dendrites with bigger grain width.

    To sum up, with the analysis made in this study, it can be concluded that the parameter range used to print HX with LMD are suitable for the fabrication of engine complex parts.

  • 85.
    Bengtsson, Carl
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Franklin, Jesper
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Utväxlingssystem för testanordning2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    New electric motors and drivelines are constantly being developed to progress with faster and more efficient electric cars. To match the growing industry it may be necessary to use existing equipment in new ways. NEVS have been requested to test electric motors with speeds up to 20 000 rpm, which they are currently not able to perform. The goal of the thesis work is to produce the foundation for an adapter system that will use the existing equipment in NEVS test cell TR6 to test directly driven electric machines with speeds up to 20 000 rpm.

    In the methods section the limitations and demands are presented in which customer needs and relevant components are depicted to serve as a foundation for the development process. Included in the development method is for example a literature study, internal and external idea generation and concept selection matrices.

    The result section describes the result of each section in the method and details the specifications of the suggested adapter system. The result section depicts the theoretical maximal load and performance of the dimensioning components and presents a concept for a complete system.

    In the discussion section relevant components, aspects of the development process and the result of the thesis work are discussed. The conclusion is that the system concept satisfies the customer needs and is a possible option to expand on TR6's test range.

  • 86.
    Bengtsson, Daniel
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Gustafsson, Karin
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Kvalitetsarbete inom mätteknik med FARO-arm2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis has been performed at Siemens Industrial Turbomachinery AB in Trollhättan. The company manufactures combustors for gas turbines. The purpose of the work has been to investigate whether qualified measurements can be performed with Siemens Industrial Turbomachinery AB's measuring instruments. This study has been performed through a measurement system analysis. The purpose has also been to investigate whether it is possible to introduce statistical process control for a detail.

    To carry out this study, the study designs case study and action research have been used. The case study has been for the measurement system analysis because it concerned a specific case that has been analyzed. Action research has been used to investigate statistical process management since the survey has been part of planning work for the introduction of an improvement. Measurements on a gauge block with known dimensions have also been made. The measurements were compiled in an Excel sheet and analyzed in Minitab. Then a VMEA was performed.

    Analysis of the measurements made it clear that the operators vary in both repeatability and reproducibility. The measuring instrument has proved to be stable and not a basis for variation. The study on implementation of statistical process control has shown that it is not possible to be introduced because the measurement results are too unstable. This leads to the company having to review its measurement methods to achieve a reduced spread of the measurement results. That the study has not used enough measuring objects for a statistically correct result should be emphasized. Consideration should therefore be taken that the result of the study is not entirely reliable, but rather indicate that it is a probable result that has emerged. Suggestions that have emerged during the study is:

    • The details are placed indoors long enough before they are measured.

    • The company introduces a separate, customized room for measuring the details.

    • The company reviews the work methodology for the measurements.

    • The company updates work instructions for measurements.

    • The company introduces measurement training for operators.

    What has not been made is the actual introduction and making of user data for statistical process control. This is because the measurement results have a too great variation for the use of SPS.

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  • 87.
    Bengtsson, Julia
    et al.
    University West, Department of Engineering Science.
    Larsson, Johan
    University West, Department of Engineering Science.
    PESTLE-analys av möjligheter och hinder för implementering av SAF i motorprovningsverksamheten och Hotspotanalys för komponenter i RM12-motorn: En dual fallstudie hos GKN Aerospace för att främja hållbarhetsarbete2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As the greenhouse effect becomes increasingly evident, economic, social, and ecological sustainability has become a larger part of international and national security policies. This puts pressure on both government institutions and private actors within the defence industry to evaluate and improve their activities in line with global sustainability goals and an increased focus on climate. GKN Aerospace has identified the need to enhance its sustainability footprint in both products and processes within its operations. In this context, this study aims to explore the possibilities of integrating sustainable aviation fuel (SAF) in GKN's engine testing operations and examine sustainability aspects related to the RM12 engine, resulting in a dual case study with two different approaches. In line with this, the study has utilized the PESTLE analysis methodology to evaluate opportunities, obstacles, and potential benefits of implementing renewable aircraft fuel in the engine testing operations. It has also employed hotspot analysis to highlight sustainability risks associated with key components of the RM12 engine. The study has reviewed relevant literature and life cycle analyses in the field, conducted observations in the engine testing operations, and carried out a series of interviews with domain experts from GKN and the Swedish Defence Materiel Administration. The results of the study show that GKN has several opportunities to improve its sustainability profile. Multiple options for potential SAF implementation have been identified, and market trends indicate a positive development for SAF. By implementing SAF, the operations can reduce their greenhouse gas emissions, but currently, challenges are linked to international availability and cost. Several sustainability aspects related to components in the RM12 engine have been identified, primarily concerning the materials in the studied components and their global supply chain. Taking these results into account, GKN can take actions to enhance its sustainability performance in the engine testing operations and address sustainability aspects related to the RM12 engine. This is crucial for reducing its climate impact and promoting a sustainable future within the defence industry. 

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  • 88.
    Bengtsson, Rebecka
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Förbättringsförslag till tejpenhet i slutpackare TS8102022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis was carried out in the spring of 2022 at Graniten Engineering in Uddevalla, a company that mainly offers machine solutions for pharmaceutical manufacturing and healthcare automation. With the vision of being one of the world's most innovative automation companies that helps its customers increase their productivity and reduce their impact on the environment, Graniten's machine solutions are mainly characterized by a high flexibility, short changeover time and a low footprint. 

    One of Graniten's machine solutions is an End of Line packer, TS810, whose task is to package medical packages in a larger box, seal it and then place it on an European pallet. The sealing of the carton is carried out by the tape sealing unit, which today there are some problems with which leads to unnecessary time of downtime. Therefore, the focus of this thesis is to develop a proposal to improve today's tape sealing unit with the intention of minimizing today's problems and decrease the downtime. The project begins with a current situation analysis where the tape dispenser, its function, installation dimensions and documentation are studied physically with the design engineers, assembly and service personnel who has experience with the tape sealing unit that is used inTS810 to get a comprehensive picture of today's problems. Then the survey begins and with parts from the seven quality control tools, the root of today's problems has been identified. In order to generate an improvement proposal, relevant parts of the generic product development process are applied, but also methods from quality function deployment and risk analyzes.

    The first part of the result is a comprehensive picture of the problems that can be linked to the tape unit and why these problems arise. The second part of the result is a complete documentation in terms of assembly-drawings, detail-drawings and a simpler cost calculation of the improvement proposal. All in all, the work is considered successful because the goal has been achieved. The improvement proposal eliminates a number of problems that can be linked to the tape unit, but not all.

    The improvement proposal could have eliminated more problems and satisfied more customer needs in order to generate a better result for Graniten. The improvement proposal can be ordered and assembled if desired.

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  • 89.
    Bengtsson, Victor
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Svantesson, David
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Teknisk och ekonomisk analys av svetsmetoden HF-TIG i Ti-6Al-4V2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GKN Aerospace Sweden AB belongs to one of the four divisions within GKN and has most of its operations in Trollhättan, where development, manufacturing and maintenance are performed on components for jet engines. GKN is more than 250 years old and has nearly 60 000 employees, of whom approximately 2 200 works in Trollhättan.

    The aim of the thesis was to evaluate the high frequency tungsten inert gas (HF-TIG) welding method technically and economically for potential future implementation in GKN's production. The hope is that the welding method can contribute to a more stable manufacturing process with fewer delays and reduced quality deficiency costs on the product XWB-ICC (Xtra Wide Body – Intermediate Compressor Case), where today conventional TIG welding is applied. The existing welding method creates deviations in the quality of certain weld joints due to high thermal impact, and according to previous studies, HF-TIG should have a lower thermal impact on the material compared to conventional TIG welding. The project group, in consultation with the supervisors at GKN and University West, has delineated the work to titanium plates with 1.5mm thickness which has been welded "bead-on-plate" without filler material during the experiments.

    Literature studies in HF-TIG, design of experiments, investment assessment and quality deficiency costs have combined with welding experiments, data collection, measurement of results and meetings with staff at GKN contributed to good knowledge of HF-TIG technical and economic impact on GKN. This has been evaluated and compiled to be able to report a technical and financial result for a potential future implementation.

    In the study's design of experiment, the tip angle of the electrode, frequency, balance and the relationship between background current and peak current have been selected as factors to be investigated. The result shows that all factors affect the measured welding results in one way or another. This provides an understanding of the welding process and indicates which factors can reduce costs, caused by lack of quality.

    In conclusion, project participants together with GKN supervisors estimated a 25% reduction of quality deficiency costs for five specific welds on XWB-ICC. The result shows that an implementation of HF-TIG is economically profitable for GKN.

  • 90.
    Bennulf, Mattias
    University West, Department of Engineering Science, Division of Production Systems.
    A User-Friendly Approach for Applying Multi-Agent Technology in Plug & Produce Systems2020Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis presents methods for simplifying the use of multi-agent systems in Plug & Produce. The demand for customized products and low volume production is constantly increasing. The industry has for many years used dedicated manufacturing systems where it is difficult and expensive to adapt to new product designs. Instead, factories are forced to use human workers for certain tasks that demand high flexibility and rapid adaption for new product designs. Several solutions have been proposed over the years to create highly flexible automation systems that automatically handles rapid adaption for new products. A concept called Plug & Produce aims at creating a system where resources and parts can be added in minutes rather than days in dedicated systems. One promising solution for implementing Plug & Produce is the distributed approach called multi-agent systems, where each resource and part get its own controller that communicates with each other to reach manufacturing goals. The idea is that the system automatically handles the adaption for new products. However, still today the use of such systems is extremely limited in the industry. One reason is the lack of mature multi-agent systems that are easy to use and that hides the complexity of the underlying agent system from the users. This is a huge problem since these systems tend to be more complex than traditional approaches. Thus, this thesis focuses on simplifying the use of multi-agent systems by proposing various methods for bringing the multi-agent technology for Plug & Produce closer to the industry.

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  • 91.
    Bennulf, Mattias
    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.
    A Method for Configuring Agents in Plug & Produce Systems2022In: SPS2022: Proceedings of the 10th Swedish Production Symposium / [ed] Amos H.C. Ng, Anna Syberfeldt, Dan Högberg, Magnus Holm, IOS Press, 2022, Vol. 21, p. 135-146Conference paper (Refereed)
    Abstract [en]

    Multi-agent technology, used for implementing Plug & Produce systems have many proposed benefits for fast adaption of manufacturing systems. However, still today multi-agent technology is not ready for the industry, due to the lack of mature supporting tools and guidelines. The result is that today, multi-agent systems are more complicated and time-consuming to use than traditional approaches. This hides their true benefits. In this paper, a new method for configuring agents is presented that includes automated deployment to manufacturing systems and by its flexible design opens the possibility to connect many other supporting tools when needed. A configuration tool is also designed that works with the proposed method by connecting to an agent configuration database. The overall aim of the method is to simplify the steps taken for adapting a manufacturing system for new parts and resources.  

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  • 92.
    Bennulf, Mattias
    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.
    Lennartson, Bengt
    Department of Signals and systems, Chalmers University of Technology (SWE).
    Goal-Oriented Process Plans in a Multiagent System for Plug & Produce2021In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 17, no 4, p. 2411-2421Article in journal (Refereed)
    Abstract [en]

    This article presents a framework for Plug & Produce that makes it possible to use configurations rather than programming to adapt a manufacturing system for new resources and parts. This is solved by defining skills on resources, and goals for parts. To reach these goals, process plans are defined with a sequence of skills to be utilized without specifying specific resources. This makes it possible to separate the physical world from the process plans. When a process plan requires a skill, e.g., grip with a gripper resource, then that skill may require further skills, e.g., move with a robot resource. This creates a tree of connected resources that are not defined in the process plan. Physical and logical compatibility between resources in this tree is checked by comparing several parameters defined on the resources and the part. This article presents an algorithm together with a multiagent system framework that handles the search and matching required for selecting the correct resources.

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  • 93.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Production Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Anderberg, Staffan
    University West, Department of Engineering Science, Division of Process and Product Development.
    Green machining: improving the bottom line2009Conference paper (Other academic)
    Abstract [en]

    The aim of this paper is to present how Green machining can be established in the metal working industry for taking immediate actions towards a more environmental friendly manufacturing, but also to address areas for research in order to advance towards a more sustainable manufacturing industry. An often overlooked approach is to use the knowledge about the specific cutting energy and its dependency upon machining parameters in order to establish a machining strategy that leads towards a more energy efficient production, but also contributes to increased productivity and thereby improving the bottom line as well. The paper has a production preparation perspective and thus presents the areas where a green machining strategy is applicable.

  • 94.
    Beno, Tomas
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Isaksson, Marina
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Pejryd, Lars
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Investigation of Minimal Quantity Cooling Lubrication in Turning of Inconel 7182007In: Proceedings of the 3rd International Conference on Tribology in Manufacturing Processes: ICTMP 2007, Yokohama, Japan 24-26 September, 2007, p. 281-286Conference paper (Other academic)
  • 95.
    Beno, Tomas
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Isaksson, Marina
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Pejryd, Lars
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Investigation of Minimal Quantity Lubrication in Turning of Waspalloy2007In: Advances in Life Cycle Engineering for Sustainable Manufacturing Businesses: Proceedings of the 14th CIRP Conference on Life Cycle Engineering, Waseda University, Tokyo, Japan, June 11th-13th, 2007, Springer , 2007, p. 305-310Conference paper (Refereed)
  • 96.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Isaksson, Marina
    Pejryd, Lars
    University West, Department of Engineering Science.
    Machining aerospace material with sub-cooled minimal quantity cppling lubrication fluids2009In: World Tribology Congress 2009: Kyoto, Japan, September 6-11, 2009, p. 93-93Conference paper (Other academic)
  • 97.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes. University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Repo, Jari
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Pejryd, Lars
    Örebro Universitet.
    The Use of Machine Tool Internal Encoders as Sensors in a Process Monitoring System2013In: International Journal of Automation Technology, ISSN 1881-7629, E-ISSN 1883-8022, Vol. 7, no 4, p. 410-417Article in journal (Refereed)
    Abstract [en]

    Tool wear in machining changes the geometry of the cutting edges, which affects the direction and amplitudes of the cutting force components and the dynamics in the machining process. These changes in the forces and dynamics are picked up by the internal encoders and thus can be used for monitoring of changes in process conditions. This paper presents an approach for the monitoring of a multi-tooth milling process. The method is based on the direct measurement of the output from the position encoders available in the machine tool and the application of advanced signal analysis methods.

    The paper investigates repeatability of the developed method and discusses how to implement this in a process monitoring and control system. The results of this work show that various signal features which are correlated with tool wear can be extracted from the first few oscillating components, representing the low-frequency components, of the machine axes velocity signatures. The responses from the position encoders exhibit good repeatability, especially short term repeatability while the long-term repeatability is more unreliable.

  • 98.
    Bergling, Gustav
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Nair, Vishnu
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Cost-effective manufacturing process for plastic components in automotive industry2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A seemingly increasing trend in the automotive industry is the prevalence of hybrid and electric vehicles. For Lear Corporation, a global automotive supplier of seating and electronic systems, this has caused a decrease in quantity of their products as these types of vehicles are manufactured at lower rates of volumes. An essential element of the electronic system provided by Lear is the wire harness. The wire harness is fastened and protected through plastic components called channels or brackets. These channels are fabricated through injection molding, one of the most common plastic manufacturing processes which offer many benefits. However, injection molding entails high upfront costs which are not suitable for the lower scales of production Lear expect. This prompted the company to seek other alternative processes and thus the idea of this thesis arose.The purpose of the thesis was to identify, evaluate and present alternative manufacturing processes that could potentially replace the current process. Furthermore, the possibility of decreasing the costs of the current process and making it viable for low volume production was explored.The study presented a total of nine common plastic manufacturing processes and subsequently performed a screening where processes deemed incompatible, in terms of aspects such as part complexity, size, volume and cost, were dismissed and processes deemed compatible in relation to the desired application were evaluated further. The processes kept for further examination were injection molding and additive manufacturing.Injection molding and additive manufacturing were evaluated further and ultimately cost estimates for each process were requested to manufacturers in order to make a cost analysis and further study the feasibility of respective process.The cost estimates and subsequent cost analysis indicated that the ideal and most cost-effective option for Lear would be changing the injection molding tool to MUD, aluminum or steel grade 738. This allows Lear to utilize the benefits of injection molding while decreasing the mold cost and upfront costs for the injection molding process substantially. Another proposal presented was to merge injection molding and additive manufacturing in a method called bridge production. This would allow Lear to increase flexibility and reduce lead time.

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  • 99.
    Bergqvist, Anton
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Wellme, Andreas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kvalitetssäkring med Visionteknik: Inspektion av monterade produkter2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Tyri Sweden AB is a company that produces LED-lights for heavy vehicles. Tyri wants to investigate if machine vision can help them to assure that gaskets and membranes are assembled to ensure that the end customer doesn't get a faulty product. The purpose of the project is to create an understanding on how machine vision can be a tool to detect faulty products. The goal is to answer the question regarding if machine vision is a suitable technique to detect gaskets and membranes. Another thing that is to be investigated is whether the movement of the object and if light conditions affects the reliability of the inspection method. To answer these questions is a literature study conducted followed by an experiment with the suitable method. The company has previously done studies on threedimensional inspection methods and therefore want the focus to be on two-dimensional methods. The two-dimensional methods that are presented are traditional camera and thermal images. A suitable method is identified based on the literature study and criteria from the company. The chosen method is a smart-camera with software developed by the camera manufacturer. This method is used in an experiment with the purpose to collect data for a statistical analysis to determine how reliable the method is. The reliability is tested via hypothesis testing where it is examined how often the method makes a wrong decision. The null hypothesis states that more than one percent of the decisions are incorrect and the counter hypothesis states that less than one percent are incorrect.

    The experiment is done in a production environment that simulates the production of the company. A smart-camera is placed above a conveyer and each time a product pass below the camera a photo is captured. The photo is then analyzed in a software to identify if gaskets and membranes are assembled or not. Four test runs are conducted where gaskets and membranes are tested separately in either factory lighting or controlled lighting. From the statistical calculations based on the results from the test runs the null hypothesis can be seen as false in three of the test runs. The test run where the null hypothesis is true is when gaskets are being detected in factory lighting.

    A conclusion is then made that machine vision is a suitable method to detect if gaskets and membranes are missing. Another conclusion is that the inspection can be made in a reliable way in spite of the movement of the object as long as controlled lighting is used. Controlled lighting is not as critical if the object to inspect is standing still. Controlled lighting can be used to create shadows to optimize the accuracy of the inspection and therefore the importance of the light can be seen as situational.

  • 100.
    Bergstedt, Filiph
    et al.
    University West, Department of Engineering Science.
    Svensson, Filip
    University West, Department of Engineering Science.
    Genomlysning och förbättring av en bearbetningsoperation2023Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    This report presents work carried out at GKN Aerospace, a supplier of both civil and military aircraft engine components as well as space propulsion. Their facility in Trollhättan manufactures complex products of high quality. The company has identified a problem with robustness and time efficiency in one of their operational steps of a manufacturing process for a part. This means that the part has difficulty coping with its intended rate, which is due to the part being processed in the wrong machine in terms of material, preparation, tool changes and tool magazines. This is ensured with the help of the results and discussion chapter. The purpose of this work was to investigate and improve a turning operation, along with the goal of making the operation more robust and preparation more manageable for new and existing CAM preparers.

    To improve the process, a deeper understanding of what the limiting factors were was needed, thus basic understanding and information about the process needed to be collected. This was done with the help of observation of the machine in processing, analysis of data via software programs and numerous meetings and discussions with experienced personnel. Production engineers and operators agree on the two biggest problems to be eliminated. The first problem is about chips, including chip formation, chip breaking and machine stops. The second problem concerns tools, including tool changes, tool magazines and machine stops.

    The work resulted in the existing machine in which the part is processed, the carousel lathe Carnaghi, not being efficient enough for the operation to cope with the weekly schedule. The result is divided into two parts; one involving improvement suggestions for the existing machine, as well as one to improve the process in general.

    However, more work and future measures remain, for which this report can usefully form the basis. A new preparation with a new concept, execution of the new lathe specifications on sharp part and concept development of chip removal tools is some of the improvement proposals addressed in the report.

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