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  • 1.
    Aagaard, Sebastian
    Örebro University, School of Science and Technology.
    Demonstrating customer and business value through the implementation of a Design for Reliability Program2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is widely assumed within industry that implementation of a Design for Reliability (DfR) Program can reduce warranty costs, increase customer value and reduce Total Cost of Ownership (TCO) when applied within both product development and product improvement projects. DfR is the set of tools and related product development processes for improvement in the reliability of a product, over time through changes in the product design and the manufacturing process. This research activity aimed at demonstrating the customer and business value of implementing a DfR Program at Epiroc Surface Division. This wasinvestigated from the perspective of selected projects and product development activities focused on the Epiroc SmartROC D65 drilling rig, which has actively worked with the reliability tools.The study has concluded that implementing the DfR Program has yielded tangible business value. The enhanced Early-Life Reliability report now allows for better evaluation of business value. This value has primarily been derived from the ability to analyze reductions in warranty costs and improvements in Mean Time Between Events (MTBE), a subset of Mean Time between Failures (MTBF). A method has been developed to determine business value in terms of cost savings. From a customer perspective, when considering the TCO, it could be demonstrated that working actively with the reliability tools during product development positively affects the mechanical availability and productivity of the equipment resulting in TCO improvements. The primary tools employed in the study include the enhanced Early-Life Reliability report, and risk management tools employed during product development for early identification of potential failure modes.The study has concluded that the most significant opportunities for improving the DfR Program is by an increased collection of relevant data from the equipment’s useful life and not limited to the early life during the warranty period. Additionally, recording and reporting actual MTBFdata would be desirable to gain a broader perspective than what MTBE currently provides. Improving the quality and reliability of the input data used in tools like the Early-Life Reliability report would significantly enhance the output of this asset. It has been proven that the data can be utilized effectively. The enhanced version of the tool is not available for widespread use within the organization. However, once released, it could be a great opportunity to improve DfR in conjunction with the developed method for prioritizing efforts and demonstrating customer and business value.

  • 2.
    Abdulkareem, Ahmed
    et al.
    Örebro University, School of Science and Technology.
    Al-Radi, Omar
    Örebro University, School of Science and Technology.
    Evaluating the measured grip stiffness of different carton board material properties and geometries2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This candidate thesis reports the findings of a study on an objective method for measuring grip stiffness in carton board packages with different geometries and material properties. Syntouch Biotac and a tensile tester were used as an objective method for measuring grip stiffness. In this project tests were carried out on packages with three different grammages and two different geometries. For each grammage and geometry, ten packages were tested.

    The study identifies that the applied method for the measurement of grip stiffness works to measure the change in grip stiffness regardless of where a load was applied on a package. Furthermore, the method demonstrates reasonable results. Finally, the study concluded that the objective testing method could distinguish between different material properties and geometries of the cartons being measured.

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    Evaluating the measured grip stiffness of different carton board material properties and geometries
  • 3.
    Abu Baker Karim, Aria
    et al.
    Örebro University, School of Science and Technology.
    Schnelzer, Anna
    Örebro University, School of Science and Technology.
    Optimering av glidlager och utveckling av dess konstruktion2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    We have in this project become engrossed in a plain bearing design that is located in a screw press. The screw press compact an unknown mass that is confidential. Robustus have a suggestion to over dimensioning the present plain bearing. The aim of this project was to analyze and to do an optimization on some plain bearings and compare them to the present bearing and to take the choice of material and the environment where the bearing is located into account. The analysis and the optimizations showed that the current plain bearing had the best geometry but not the optimal material selection. The project is in an early state and it needs some geometrical changes. The most important of everything is that the problem has been identified with the help of the wrecked plain bearing and with an excel model.

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  • 4.
    Adolfsson, Josefine
    et al.
    Örebro University, School of Science and Technology.
    Trinh, Madeleine
    Örebro University, School of Science and Technology.
    Effektivisering av produktionsflöde för lageravdelningen2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has taken place at Martin G Anderson in Örebro, a company that manufactures window glasses. The company has problems with the last step of the process which is the warehouse, where big volume of glass and overtime working hours affects the workers. Purposes of the project is to find additional grounds for improvement suggestions increasing the efficiency of the production in the warehouse. As a part of the project, relevant data is collected to be able to describe the status report at the company. The status reports cover a process description and process mapping. To be able to find possible solutions to improve the current situation, the problems of the warehouse must be investigated. This is accomplished by a status analysis where relevant analytic tools as 5 Whys and 7+1 wastes of Lean production are used. The project plans are to maintain the PDCA cycle where the focus is to approach the phase Plan. The remaining phases of PDCA can thereafter be resumed by the company. The results show multiple wastes in the company, where parts of the wastes are non-value-added activities. The improvement suggestions are therefore aimed at eliminating or reducing these activities and in that way streamline the production flow in the warehouse department. One of the suggestions was theoretically analysed to determine if the suggestion was feasible or not, which resulted in it being possible to implement. Other suggestions are general ideas for the company in order to strive for a more standardised way of working. For continued work, Martin G Anderson should resume the PDCA cycle where the improvement suggestions will be implemented, evaluated and maintained a standard if the suggestions prove to have a good impact. Prerequisites are given in order to be able to attack other problem areas on the basis of this report.

  • 5.
    Ahari, Elias
    et al.
    Örebro University, School of Science and Technology.
    Eliasson, Erik
    Örebro University, School of Science and Technology.
    UNDERSÖKNING AV OMSTÄLLNINGSTIDER OCH VARIATIONER VID KARTONGMASKIN 2: EN FALLSTUDIE PÅ IGGESUND PAPERBOARD AB, IGGESUND2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Iggesund Mill manufactures bleached board that is used in exclusive packaging. Iggesund Mill is a part of the Holmen Groupand is located almost 30 scandinavian miles north of Stockholm. A strategic initiative has been launched at Iggesund Mill, which includes improving the working environment, increasing participation and increasing the ability to produce high quality board.

    In this study, changeovers and the variations that occur on the board machine 2 (KM2)have been investigated. This work has been conducted as a qualitative case study where interviews and observations have been analyzed with theoretical support. Early in the study it proved difficult to determine the changeover times at KM2. This may be due to an uncertainty regarding how to report changeovers, which creates a misleading picture of the changeover problems. The conclusion of this is that Iggesund Mill should clearly define the term "Changeover". The variety of products also leads to a lot of changeovers which leads to variations in the process that adversely affect the productivity. A recommendation for a continued work is to investigate whether the product variety can be reduced or the possibility to run larger production cycles.

  • 6.
    Al Karawi, Osama
    Örebro University, School of Science and Technology.
    Minimering av kassation i CNC processer.2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nobel Biocare is one of the world's leading companies in the manufacture of dental implants. The company is in many places around the world. The degree project was carried out at the N1 department in Karlskoga.  The company's goal is to create smart workshops and to do so, it is necessary that weaknesses in the production are identified. To find solutions, it is necessary to identity the weaknesses so that they do not arise again.  The purpose of this work is to identify the root causes of scrapping in the CNC processes and then propose three solutions to reduce/eliminate these problems. The company wants to know what opportunities they have and how they need to improve to create smart CNC workshops in 2-3 years.  To investigate the root causes of scrapping, several different analyzes were initially performed using Excel, where documented company data was used. Operators were interviewed and their own observations were noted during the visits to Nobel Biocare.  

    The study resulted in that the company should implement a timer for each operator, change tools after a certain time and have a review of how the vacuum pressure is regulated. The root cases are focused on method and man, and they are that there is a lack of quality assured routine for setting cutting fluid, tools are changed too late, inefficient method in vacuum control, sensitive tools lack sensors and too many devices are produced before control.  

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  • 7.
    Alexandersson, Tobias
    Örebro University, School of Science and Technology.
    Examensarbete Moelven Valåsen AB.2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Moelven Valåsen AB sawmill will within a 5-year period increase production from 375,000 𝑚3to approximately 500,000 𝑚3per year by building a new saw line. This has more led to the company going up from 2 shifts to 3 shifts to be able to meet this demand. This has led to the finished goods inventory before the customer has become full, and as a result the company has had to stand still. To investigate this, this thesis has investigated what the flow of the finished goods inventory looks like with the help of some tools to analyze the flow but at the same time develop the problems that may be the basis for this problem of the inventory becoming full. What has been concluded is that there are many different challenges to solving this problem. This thesis has provided an overview of where the problem may be in the flow and what it is due to. What has also been developed are some improvement proposals that could benefit the company and be developed so that the capacity of the warehouse can increase and become more efficient.  

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  • 8.
    Alfredsson, Axel
    et al.
    Örebro University, School of Science and Technology.
    Knutson, Gustav
    Örebro University, School of Science and Technology.
    Analys av driftstopp i ett hyvleri2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Moelven is an industrial group that produces building materials and systems for the construction industry; with its 52 productions units in Norway, Sweden and Denmark, it is one of the biggest in Scandinavia. This study has been carried out in the planing mill at Moelven Valåsen Wood AB in Karlskoga.

    Because of the low utilization rate in the planing mill (65%), it constitutes a bottleneck, meaning it limits the capacity and flow of material, for most of the products. The purpose of the study was to analyze the stoppage in the planing mill in order to make recommendations on how the utilization rate can be increased.

    The study began with a wide perspective to identify the reasons behind this problem. A summary of all stops in the planing mill concluded that set ups of the planer made up for 30% of total stoppage. Because of this, the study was narrowed down to mainly analyze the different types of set ups, which was done through extensive observations and videotaping. The solutions and recommendations that were given are therefore almost entirely regarding set up-time reduction, and more specifically, milling set ups. The recommendations, based on the results of the study, includes:

    • Suggestions on how to separate internal and external set up.

    • Better order of tools through designing a check table.

    Standardizing the procedure by creating a routine and dividing the operators into different work roles.

    Involving everyone in the organization in order to work with continuous improvement.

    A simulation of milling set ups was done by implementing parts of the recommendations – this resulted in a setup up-time reduction of 13 minutes, which corresponds to 32.5%. Because of common denominators, such as movements, the recommendations given are likely generalizable for all set ups.

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    Analys av driftstopp i ett hyvleri
  • 9.
    Alfredsson, Svea
    Örebro University, School of Science and Technology.
    Algas mikrofilter – alternativ till testfilter2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Transporting machines and products all over the world is expensive, time-consuming, and environmentally burdensome. Cellwood Machinery is today sending a 650-kilogram test filter to potential customers so that they can evaluate the benefits of the Algas microfilter product. The customers are paper mills all over the world and Alga's microfilters are used to filter the process water needed in paper manufacturing. The company does not think that the current method is sustainable, neither financially, in terms of time or environmentally, and therefore wants to find an alternative.The task of the thesis is to find a different method than sending a test filter. The applied method must make it possible to evaluate properties of filtered process water. It also needs to be explained which factors affect the dimensioning of an Algas microfilter.In order to find an alternative to the test filter, various concept proposals have been developed. Among these, the concept proposal to use a Schopper Riegler meter in combination with a scale stood out as the best. A Schopper Riegler meter is a measuring instrument common in the paper industry. The concept has also been tested in Cellwood Machinery's laboratory. The results of these tests showed that the concept solution works. Since the tests were done in the laboratory, further work is needed to ensure that the presented solution can fully function as an alternative to the test filter. 

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  • 10.
    Algesten, Johannes
    et al.
    Örebro University, School of Science and Technology.
    Svedberg, Sofie
    Örebro University, School of Science and Technology.
    KONSTRUKTION AV AUTOMATISK PÅHASPLINGSPROCESS VID TILLVERKNING AV BANDSTÅL2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The mission that we have received is to design a device that will automate the coiling processin the manufacture of steel strip. The goal of this project is to develop a production documentation that will form the basis for further development of the product. The production documentation shall include drawings, list of components and a cost estimate. A pilot study was conducted where we visited one of the largest strip steel manufacturer to investigate the solutions they had to our problem. Based on what we saw, a concept generation was made that led to the concept that we proceeded with. In the process, we have placed great emphasis on making the design as simple as possible to get a reasonable production cost. We have also taken into account that the design will be integrated with existing equipment. Regarding cost, we have as far as possible tried to use standard components and standard dimensions of the material in the construction. Parts of the structure exposed to high forces have been analyzed by using ANSYS. The result is a construction with two arms using a belt to envelope the coil. The arm is controlled using a hydraulic cylinder, while the other is positioned when the belt is stretched. The construction will be placed above the coil and lowered when it is used.

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    KONSTRUKTION AV AUTOMATISK PÅHASPLINGSPROCESS VID TILLVERKNING AV BANDSTÅL
  • 11.
    Alijagic, A.
    et al.
    Örebro University, School of Science and Technology. Inflammatory Response and Infection Susceptibility Center (iRiSC).
    Scherbak, N.
    Örebro University, School of Science and Technology.
    Kotlyar, O.
    Örebro University, School of Science and Technology.
    Karlsson, P.
    Örebro University, School of Science and Technology. Department of Mechanical Engineering.
    Persson, A.
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Center (iRiSC).
    Hedbrant, A.
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Center (iRiSC).
    Norinder, U.
    Örebro University, School of Science and Technology.
    Larsson, M.
    Örebro University, School of Science and Technology.
    Felth, J.
    Uddeholms AB, Hagfors, Sweden.
    Andersson, L.
    Örebro University, School of Medical Sciences. Örebro University Hospital. Inflammatory Response and Infection Susceptibility Center (iRiSC); , Department of Occupational and Environmental Medicine.
    Särndahl, E.
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Center (iRiSC).
    Engwall, M.
    Örebro University, School of Science and Technology.
    Cell Painting unveils cell response signatures to (nano)particles formed in additive manufacturing2022In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, P17-01, Vol. 368, no Suppl. 1, p. S226-S227, article id P17-01Article in journal (Other academic)
  • 12.
    Alijagic, Andi
    et al.
    Örebro University, School of Science and Technology. School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Engwall, Magnus
    Örebro University, School of Science and Technology.
    Särndahl, Eva
    Örebro University, School of Medical Sciences.
    Karlsson, Helen
    Department of Health, Medicine and Caring Sciences, Occupational and Environmental Medicine Center in Linköping, Linköping University, Linköping, Sweden.
    Hedbrant, Alexander
    Örebro University, School of Medical Sciences.
    Andersson, Lena
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Occupational and Environmental Medicine.
    Karlsson, Patrik
    Örebro University, School of Science and Technology.
    Dalemo, Magnus
    Absolent AB, Lidköping, Sweden.
    Scherbak, Nikolai
    Örebro University, School of Science and Technology.
    Färnlund, Kim
    AMEXCI AB, Karlskoga, Sweden.
    Larsson, Maria
    Örebro University, School of Science and Technology.
    Persson, Alexander
    Örebro University, School of Medical Sciences.
    Particle Safety Assessment in Additive Manufacturing: From Exposure Risks to Advanced Toxicology Testing2022In: Frontiers in Toxicology, E-ISSN 2673-3080, Vol. 4, article id 836447Article, review/survey (Refereed)
    Abstract [en]

    Additive manufacturing (AM) or industrial three-dimensional (3D) printing drives a new spectrum of design and production possibilities; pushing the boundaries both in the application by production of sophisticated products as well as the development of next-generation materials. AM technologies apply a diversity of feedstocks, including plastic, metallic, and ceramic particle powders with distinct size, shape, and surface chemistry. In addition, powders are often reused, which may change the particles' physicochemical properties and by that alter their toxic potential. The AM production technology commonly relies on a laser or electron beam to selectively melt or sinter particle powders. Large energy input on feedstock powders generates several byproducts, including varying amounts of virgin microparticles, nanoparticles, spatter, and volatile chemicals that are emitted in the working environment; throughout the production and processing phases. The micro and nanoscale size may enable particles to interact with and to cross biological barriers, which could, in turn, give rise to unexpected adverse outcomes, including inflammation, oxidative stress, activation of signaling pathways, genotoxicity, and carcinogenicity. Another important aspect of AM-associated risks is emission/leakage of mono- and oligomers due to polymer breakdown and high temperature transformation of chemicals from polymeric particles, both during production, use, and in vivo, including in target cells. These chemicals are potential inducers of direct toxicity, genotoxicity, and endocrine disruption. Nevertheless, understanding whether AM particle powders and their byproducts may exert adverse effects in humans is largely lacking and urges comprehensive safety assessment across the entire AM lifecycle-spanning from virgin and reused to airborne particles. Therefore, this review will detail: 1) brief overview of the AM feedstock powders, impact of reuse on particle physicochemical properties, main exposure pathways and protective measures in AM industry, 2) role of particle biological identity and key toxicological endpoints in the particle safety assessment, and 3) next-generation toxicology approaches in nanosafety for safety assessment in AM. Altogether, the proposed testing approach will enable a deeper understanding of existing and emerging particle and chemical safety challenges and provide a strategy for the development of cutting-edge methodologies for hazard identification and risk assessment in the AM industry.

  • 13.
    Almerstedt, Matilda
    et al.
    Örebro University, School of Science and Technology.
    Lindhé, Johanna
    Örebro University, School of Science and Technology.
    Empirisk studie i form och geometrins upplevda inverkan på konsument produkter2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    It is unclear which mechanical properties that affect consumer products, it can be assumed that the shape and geometry affect the perceived feeling of consumer products. The aim of the project is to examine how the geometry and folding views affect the feeling in the use of consumer products.The study was performed on three consumer products of different dimensions where each product was produced in two different versions. The results showed that consumer product’s geometry is significant, while the folding views do not have a significant impact.

  • 14.
    Almér, Ida
    et al.
    Örebro University, School of Science and Technology.
    Hed, Johanna
    Örebro University, School of Science and Technology.
    Utveckling av delningsarm2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes a bachelor degree project conducted at the company EMBA Machinery AB. The company manufactures corrugated cardboard conversion machines. The machines convert cardboard sheets into folded corrugated boxes. EMBA´s machines are so-called internal machines that consist of several devices. The unit involved in the thesis work reported herein was the unit Counter Stacker. The Counter Stacker is the last unit in the EMBA machines, it counts and divides the finished cardboard boxes into bundles.

    EMBA wanted the authors to redesign the function that divides the sheets, the divider arm, in the affected unit. The divider arm should be controlled via electric servo operation and also act as a rebuild kit for previously sold machines.

    Calculations to investigate the stresses that arise at critical points in the design have been carried out. Motion profiles have been developed and motors and gearboxes have been dimensioned. Parallel to this a 3D-model was created in CAD. Based on the CAD-model, the company can proceed with creating complete drawing documents.

  • 15.
    Alnajar, Abdallah
    et al.
    Örebro University, School of Science and Technology.
    Jacobsson, Tobias
    Örebro University, School of Science and Technology.
    Produktutvecklingsprocess inom cirkulärekonomi2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the execution of a bachelor's thesis. The work was conducted at the company WA3RM AB, whose business idea is to create value from unused resources in industries by connecting various stakeholders and achieving circular economy with the aim of reducing climate impact and achieving the global goals for sustainable development.

    WA3RM identified the need to map the work processes in product development projects, as the company intends to industrialize more products in the future. As part of WA3RM:s mapping of product development projects, the purpose of the thesis work was to create a process for concept selection in product development projects. The process was adapted to WA3RM:s needs, and the goal of the thesis work was to answer how a sustainability perspective can be established in the concept selection phase of product development projects.

    The thesis work was conducted using the Plan, Do, Check, Act method to structure and divide the work into sub-problems. Problem areas and limitations were defined and a mapping at the company was performed. A literature review was conducted based on the results of the mapping to identify tools and methods for the final proposal, the concept selection process.

    The mapping identified three main areas: requirements and goals, sustainability, and circular economy, which formed the basis for the literature review and the proposal, the concept selection process. The concept selection process consists of four phases, where applications are divided, ranked, generated to products, and finally ranked again. At the end of the process, the project team should have a basis for discussion to provide recommendations to the organization, regarding concept selection for further development in product development projects.

    A conclusion drawn from the thesis work was that the methods and tools in the process allows for consideration of sustainability aspects. However, it is important to consider other perspectives such as market and financing to develop feasible and competitive products, so that WA3RM can continue to industrialize products that reduce climate impact and inspire more stakeholders.

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  • 16.
    Al-Nazary, Naramsin
    et al.
    Örebro University, School of Science and Technology.
    Mirza, Daniel
    Örebro University, School of Science and Technology.
    Förbättringsarbeten i produktionsprocesser för att reducera kundreklamationer hos Volvo Construction Equipment AB.2021Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At Volvo Construction Equipment in Hallsberg there are continuous improvements and projects to streamline the manufacture of their products. A problematic area in recent times has been a high proportion of customer complaints regarding cabs, the company therefore wants improvements in cab production. This report presents a case study on the causes and measures for customer complaints, based on existing documentation and interviews at the company, as well as new studies and mapping. Implementation of the study is divided into four main phases, Mapping of production, Review of customer complaints, Examination of root causes for quality deficiencies and Development of improvement proposals. The first two phases were performed to gain an understanding of the production of cabs and the customer complaints reported to the company. The manufacturing of cabs is carried out in three main production processes, welding, painting and assembly, where the assembly process is the most problematic regarding customer complaints and is thus the focus of the study. The cab assembly process has a main flow, ONE-LINE, where all cab models go through.The review of customer complaints resulted in the study being focused on four important fault types, damaged body, forgotten component, connection of contacts and screwing, which together accounted for 63% of all customer complaints in the cab assembly process. The investigation of root causes for customer complaints was done with the help of Ishikawa diagrams for each type of fault together with employees in the company's quality department and was also supplemented during discussions with operators on the cab assembly process. This resulted in the identification of the problem areas Unclear layout of materials (1), Unclear layout of tools (2), Distracting elements in the current working method (3), Not working according to a standardized working method (4) and Lack of fault protection for connecting contacts (5) in the cab assembly process. To fix the problems, the following improvement suggestions were made: Color-coded layout, Pick-To-Light System and Standardized screws (1), Tool list (2), Method after interruption and Rules for outsiders on ONE-LINE (3), Rotation and Digital instructions (4) and Color-coded connectors and Reduction of sound level on ONE-LINE (5). The company is recommended to continue the work by further investigating identified problem areas and the presented improvement proposals to implement measures to reduce customer complaints.

  • 17.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Increasing availability of industrial systems through data stream mining2011In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 60, no 2, p. 195-205Article in journal (Refereed)
    Abstract [en]

    Improving industrial product reliability, maintainability and thus availability is a challenging task for many industrial companies. In industry, there is a growing need to process data in real time, since the generated data volume exceeds the available storage capacity. This paper consists of a review of data stream mining and data stream management systems aimed at improving product availability. Further, a newly developed and validated grid-based classifier method is presented and compared to one-class support vector machine (OCSVM) and a polygon-based classifier.

    The results showed that, using 10% of the total data set to train the algorithm, all three methods achieved good (>95% correct) overall classification accuracy. In addition, all three methods can be applied on both offline and online data.

    The speed of the resultant function from the OCSVM method was, not surprisingly, higher than the other two methods, but in industrial applications the OCSVMs' comparatively long time needed for training is a possible challenge. The main advantage of the grid-based classification method is that it allows for calculation of the probability (%) that a data point belongs to a specific class, and the method can be easily modified to be incremental.

    The high classification accuracy can be utilized to detect the failures at an early stage, thereby increasing the reliability and thus the availability of the product (since availability is a function of maintainability and reliability). In addition, the consequences of equipment failures in terms of time and cost can be mitigated.

  • 18.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Backe, Björn
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Data stream forecasting for system fault prediction2012In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 62, no 4, p. 972-978Article in journal (Refereed)
    Abstract [en]

    Competition among today’s industrial companies is very high. Therefore, system availability plays an important role and is a critical point for most companies. Detecting failures at an early stage or foreseeing them before they occur is crucial for machinery availability. Data analysis is the most common method for machine health condition monitoring. In this paper we propose a fault-detection system based on data stream prediction, data stream mining, and data stream management system (DSMS). Companies that are able to predict and avoid the occurrence of failures have an advantage over their competitors. The literature has shown that data prediction can also reduce the consumption of communication resources in distributed data stream processing. In this paper different data-stream-based linear regression prediction methods have been tested and compared within a newly developed fault detection system. Based on the fault detection system, three DSM algorithms outputs are compared to each other and to real data. The three applied and evaluated data stream mining algorithms were: Grid-based classifier, polygon-based method, and one-class support vector machines (OCSVM). The results showed that the linear regression method generally achieved good performance in predicting short-term data. (The best achieved performance was with a Mean Absolute Error (MAE) around 0.4, representing prediction accuracy of 87.5%). Not surprisingly, results showed that the classification accuracy was reduced when using the predicted data. However, the fault-detection system was able to attain an acceptable performance of around 89% classification accuracy when using predicted data.

  • 19.
    Alzghoul, Ahmad
    et al.
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Löfstrand, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Karlsson, Lennart
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Karlberg, Magnus
    Division of Computer Aided Design, Luleå University of Technology, Luleå, Sweden.
    Data stream mining for increased functional product availability awareness2011In: Functional Thinking for Value Creation: Proceedings of the 3rd CIRP International Conference on Industrial Product Service Systems, Technische Universität Braunschweig, Braunschweig, Germany, May 5th - 6th, 2011 / [ed] Hesselbach, J. & Herrmann, C., Springer Berlin/Heidelberg, 2011, p. 237-241Conference paper (Refereed)
    Abstract [en]

    Functional Products (FP) and Product Service Systems (PSS) may be seen as integrated systems comprising hardware and support services. For such offerings, availability is key. Little research has been done on integrating Data Stream Management Systems (DSMS) for monitoring (parts of) a FP to improve system availability. This paper introduces an approach for how data stream mining may be applied to monitor hardware being part of a Functional Product. The result shows that DSMS have the potential to significantly support continuous availability awareness of industrial systems, especially important when the supplier is to supply a function with certain availability.

  • 20.
    Amjad, Milad
    et al.
    Örebro University, School of Science and Technology.
    Hawash, Rammi
    Örebro University, School of Science and Technology.
    Identifiering av brister i interna flödet & kommunikation med hjälp av Lean2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, many companies aim to implement Lean Production in their organizations through different approaches, methods and tools. The company where this project was carried out is active in the plastic film industry and are now aiming to work with the implementation of Lean. Amongst their products there are sealing tape, and ostomy pouches for the pharmaceutical industry. In this project, the sealing tape is the product which has been in focus. The company currently has problems such as bottlenecks within the production but also communication problems between departments and employees.

    The project was based on identifying deficiencies, wastes, and finding out the reasons why the communication is inadequate within the organization. This applies to the entire production process. With the help of tools within Lean and other improvements related to communication, a few deficiencies could be identified. A model was used for the basis of how the authors could move on to find the right tools to follow up and identify the problems. By following up on these problems, several improvement proposals have been presented to reduce and eliminate wastes that do not create value. Additional measures have been taken into action to continue to work on continuous improvements.

  • 21.
    Amouri, Alean
    et al.
    Örebro University, School of Science and Technology.
    Achhab, Rayan
    Örebro University, School of Science and Technology.
    Automatisering av packningsprocess hos Nobel Biocare AB2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nobel Biocare is an international medical technology company that manufactures dental implants which are used by licensed doctors for patients with dental problems who want to improve their oral health. The company is currently interested in Industry 4.0 and wants to upgrade into smart workshops through digitization and automation. This project's problem area is one of several areas that need improvement in Nobel, which in the long term can lead to Industry 4.0 and a smarter workshop. The packaging process in the company is today, to some extent, automated where an automatic machine is used for packaging implant articles (IP). In order for the products to be packed in the machine, it is required that an operator loads the articles one at a time onto a conveyor belt. This manual work activity that is performed by the operator today is repetitive, time consuming and laborious, which makes automation of interest. Thus, this thesis aims to generate and develop an efficient and practical solution for loading articles on the conveyor belt through automation or other solutions. The problem has been addressed by first mapping the current situation with the help of interviews, observations, document studies and time study to establish a value stream map. At the next step, requirements and desires were identified in a requirements specification and then solution proposals were generated with brainstorming and market research. Furthermore, external companies working with automation solutions were contacted to investigate whether the ideas developed are feasible. In connection with company contact, the result was developed and evaluated through an elimination matrix and a weighted criteria matrix. 

    Based on the weighted criteria matrix, it emerged that the best solution for the problem is a combination of a conveyor belt, magazine and two collaborative robots. Investing in the solution proposal means, among other things, a saving in manpower and time, which is presented in a value stream map of the future state. For further work, the solution should be studied further and tested before implementation. 

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  • 22.
    Amouzgar, Kaveh
    et al.
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Rashid, Asim
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Strömberg, Niclas
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden.
    Multi-objective optimization of a disc brake system by using SPEA2 and RBFN2013In: ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference: Volume 3B: 39th Design Automation Conference, New York: ASME Press, 2013Conference paper (Other academic)
    Abstract [en]

    Many engineering design optimization problems involve multiple conflicting objectives, which today often are obtained by computational expensive finite element simulations. Evolutionary multi-objective optimization (EMO) methods based on surrogate modeling is one approach of solving this class of problems. In this paper, multi-objective optimization of a disc brake system to a heavy truck by using EMO and radial basis function networks (RBFN) is presented. Three conflicting objectives are considered. These are: 1) minimizing the maximum temperature of the disc brake, 2) maximizing the brake energy of the system and 3) minimizing the mass of the back plate of the brake pad. An iterative Latin hypercube sampling method is used to construct the design of experiments (DoE) for the design variables. Next, thermo-mechanical finite element analysis of the disc brake, including frictional heating between the pad and the disc, is performed in order to determine the values of the first two objectives for the DoE. Surrogate models for the maximum temperature and the brake energy are created using RBFN with polynomial biases. Different radial basis functions are compared using statistical errors and cross validation errors (PRESS) to evaluate the accuracy of the surrogate models and to select the most accurate radial basis function. The multi-objective optimization problem is then solved by employing EMO using the strength Pareto evolutionary algorithm (SPEA2). Finally, the Pareto fronts generated by the proposed methodology are presented and discussed.

  • 23.
    Amouzgar, Kaveh
    et al.
    Department of Mechanical Engineering, School of Engineering, Jönköping University, Jönköping, Sweden .
    Strömberg, Niclas
    Department of Engineering Science, University West, Trollhättan, Sweden.
    An approach towards generating surrogate models by using RBFN with a priori bias2014In: Proceedings of the ASME International Design Engineering Technical Conferences & Computers and Information in Engineering Conference, 2014, Vol. 2B, New York, USA: ASME Press, 2014, article id V02BT03A024Conference paper (Refereed)
    Abstract [en]

    In this paper, an approach to generate surrogate modelsconstructed by radial basis function networks (RBFN) with a prioribias is presented. RBFN as a weighted combination of radialbasis functions only, might become singular and no interpolationis found. The standard approach to avoid this is to add a polynomialbias, where the bias is defined by imposing orthogonalityconditions between the weights of the radial basis functionsand the polynomial basis functions. Here, in the proposed a prioriapproach, the regression coefficients of the polynomial biasare simply calculated by using the normal equation without anyneed of the extra orthogonality prerequisite. In addition to thesimplicity of this approach, the method has also proven to predictthe actual functions more accurately compared to the RBFNwith a posteriori bias. Several test functions, including Rosenbrock,Branin-Hoo, Goldstein-Price functions and two mathematicalfunctions (one large scale), are used to evaluate the performanceof the proposed method by conducting a comparisonstudy and error analysis between the RBFN with a priori and aposteriori known biases. Furthermore, the aforementioned approachesare applied to an engineering design problem, that ismodeling of the material properties of a three phase sphericalgraphite iron (SGI) . The corresponding surrogate models arepresented and compared

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  • 24.
    Amouzgar, Kaveh
    et al.
    Product Development Department, School of Engineering, Jönköping University, Jönköping, Sweden; School of Engineering Science, University of Skövde, Skövde, Sweden.
    Strömberg, Niclas
    Örebro University, School of Science and Technology. Department of Mechanical Engineering.
    Radial Basis Functions as Surrogate Models with A Priori Bias in Comparison with a Posteriori Bias2017In: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 55, no 4, p. 1453-1469Article in journal (Refereed)
    Abstract [en]

    In order to obtain a robust performance, the established approach when using radial basis function networks (RBF) as metamodels is to add a posteriori bias which is defined by extra orthogonality constraints. We mean that this is not needed, instead the bias can simply be set a priori by using the normal equation, i.e. the bias becomes the corresponding regression model. In this paper we demonstrate that the performance of our suggested approach with a priori bias is in general as good as, or even for many test examples better than, the performance of RBF with a posteriori bias. Using our approach, it is clear that the global response is modelled with the bias and that the details are captured with radial basis functions. The accuracy of the two approaches are investigated by using multiple test functions with different degrees of dimensionality. Furthermore, several modeling criteria, such as the type of radial basis functions used in the RBFs, dimension of the test functions, sampling techniques and size of samples, are considered to study their affect on the performance of the approaches. The power of RBF with a priori bias for surrogate based design optimization is also demonstrated by solving an established engineering benchmark of a welded beam and another benchmark for different sampling sets generated by successive screening, random, Latin hypercube and Hammersley sampling, respectively. The results obtained by evaluation of the performance metrics, the modeling criteria and the presented optimal solutions, demonstrate promising potentials of our RBF with a priori bias, in addition to the simplicity and straight-forward use of the approach.

  • 25.
    Ander, Rebecka
    Örebro University, School of Science and Technology.
    Effektivisering av materialflödet genom processkartläggning2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    How does the current process look like and how can it be improved? That was the two questions that the company posed. That was the beginning for this degree project. Through process mapping and analysis of today's process, a proposal for development of the internal material flow has been made.

  • 26.
    Andersson, Alexander
    et al.
    Örebro University, School of Science and Technology.
    Hjelmqvist, Rasmus
    Örebro University, School of Science and Technology.
    Värdeflödeskartläggning och slöserier2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Atria Scandinavia is a company belonging to the Atria Group which is one of the largest companies in the food industry in Finland. One of their factories is located in Sköllersta, Sweden, that produce sausages, burgers and whole-meat products.

    Two products of whole-meat department was in need of a value stream mapping because the current time studies of the processes were no longer relevant. One of the products are one of the most common and oldest in Atria, sliced whole-muscle and the other a poultry product that is one of the newest. In order to calculate the cost of the sold goods in a correct manner an updated time-study was required.

    Value Stream Mapping is a powerful tool from the Lean philosophy that gives the company a very good overview of the value stream and all processes. This provides good opportunity for a deep understanding of the processes and value-flows, something that is vital for further improvement. The work with value stream analysis generated following results:

    • Updated time studies

    • Process descriptions

    • Value Stream Maps

    • Presentation of the value-adding as well as non-value-adding time

    • A kinship chart with problem areas in the value flows of the products

    • Possible root causes of problems in the flows

    • Proposed measures to handle these problems

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  • 27.
    Andersson, Cecilia
    Örebro University, School of Science and Technology.
    Automation av kvalitetskontroller2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nobel Biocare is a world leading company in the manufacture of dental implants. The implants are made of titanium and must be packed sterile to protect the implants from unwanted particles. The package used is a blister pack that is glued together in a blister machine. Three different quality controls are done manually to ensure that the packaging meets the requirements for medical manufacture. The quality controls are time-consuming and involve unnecessary disposal.  The purpose of this thesis was to investigate the possibility of this process being automated. Automation would mean that savings can be made for time and materials. It would also mean that a relatively large floorspace could be freed up in the packing room. The surface currently holds two tables that contains various equipment used to perform the manual quality controls. In consultation with the company the investigation was focused on using a vision system for automation. Since the blister packs mostly consists of plastic the lighting for the vision system was considered to be the biggest challenge. Lighting tests were performed at Prevas in Karlstad where a vision camera and different types of lights were used. The result shows that the blister packs contain fluorescent glue that became visible in UV light. This means that UV light can be used to automate the process with a vision system.  Finally, various companies were contacted, including Karlskoga Automation and Neurolearn. All companies that were contacted work with creating automation solutions and that made the contact important for this thesis. The companies to which the project was presented, they all considered it to be achievable. They also could deliver such a solution for Nobel Biocare.  

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  • 28.
    Andersson, Daniel
    et al.
    Örebro University, School of Science and Technology.
    Lindkvist, Marcus
    Örebro University, School of Science and Technology.
    Magnetbroms i liftvinsch2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ski resorts have a problem that their lift winches need regular service of the brakes, ie. the brakes on the individual T-bars. This means that ski lift operators have to shut down their facilities and bring in service personnel, which costs resources. By replacing the current brake system with magnetic brakes, the need for service would decrease.

    The new magnetic brakes must be designed to have different braking action when extending the lift winch line, compared to when it is retracted, and must also be able to fit into the existing lift winch housing. The problem herein solved, was defined as a product development assignment.

    Several ideas were generated by an idea generating process and a selection process was conducted to develop a final concept that meets all design criteria and significantly extends the service intervals.

    The design process carried out included that a number of tests were carried out and principle calculations were made on parts of the structure. The final concept is a magnetic brake that requires minimal service and also solves the problem of different braking performance depending on whether the lift line is extended or retracted. Further work includes developing a process for adapting the current lift winches too accept mounting the magnetic brake. Further work also include additional detailed development of the magnetic brake components.

  • 29.
    Andersson, Filip
    Örebro University, School of Science and Technology.
    Kartläggning - Spårbarhet2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a thesis project that maps the traceability of the production of a gear article in a manufacturing plant. Traceability is a concept that deals with the ability to obtain all information linked to a product or process throughout its life cycle. Traceability is becoming increasingly important in manufacturing to meet legal requirements, control processes and track quality deviations. The purpose of the thesis project is for the company to gain a higher quality assurance in its manufacturing process by mapping the current production and information flow and identifying deficiencies from a traceability perspective. Based on interviews with employees and observations of the manufacturing process, flow charts, spaghetti diagrams, Ishikawa diagram and 5 how, have been created to describe and analyze the current manufacturing flow and its traceability deficiencies. The work has identified several different traceability deficiencies where supplier information can be mixed and lost in production, mislabeling of gears occurs and information generated in the manufacturing process is not used. When continuing work, it is recommended to examine other production flows to ensure which deficiencies recur systematically. It is also recommended to investigate the possibility of better identification marking on the gears to enable a better traceability system where all relevant information can be stored and interconnected. 

  • 30.
    Andersson, Henrik
    Örebro University, School of Science and Technology.
    Yt- och strukturpåverkan vid finfräsning av härdat verktygsstål2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this thesis, investigations on hardened finish milled surfaces was done in collaboration with the tool steel manufacturer Uddeholms AB in Hagfors, Sweden. The steel material is affected by machining operations, sometimes in a negative destructive manner. An experimental test series containing a total of 90 surfaces in hot work steels Uddeholm Orvar Supreme and Uddeholm Dievar were milled, measured and evaluated to clarify the milling operations effect on the steels mechanical properties. It was found that the material is affected differently according to how the milling was preformed and with which type of milling tool. In this thesis, only solid carbide end-radius milling tools were used. The surface analysis were conducted with a range of measuring techniques including optical surface roughness measurements, hardness measurements in Vickers scale, residual stress measurements with X-ray diffraction (XRD) and microstructural analysis with optical light microscope. These measurements were conducted in order to determine the milling operations mechanical affects and grade of alteration of the tool steels surfaces. In the least favorable cases, the effect from machining are so profound, that degradation of produced components can be expected in terms of fatigue wear resistance. The goal of the thesis is to identify the most favorable process parameters, in order to minimize degradation of the tooling material in customer user cases, together with the opportunity to give fact based advice to Uddeholms AB customers on the most favorable process parameters in finish milling with radius-mills of hardened hot work tool steels. In this way the customer can utilize the tooling material at its full potential.  

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  • 31.
    Andersson, Joakim
    et al.
    Örebro University, School of Science and Technology.
    Bertilsson, Jimmy
    Örebro University, School of Science and Technology.
    SETUP TIME OPTIMIZATION2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

     

    Emhart Glass Ltd is a world leader in glass bottle manufacturing. They design automated machines that shape glass bottles. In Sweden there are two factories, one in Örebro and one in Sundsvall. In Örebro they manufacture primarily spare parts and new parts for the machines while they in Sundsvall assemble the machines. There are a total of 15 factories and offices around the world with the headquarter located in Swiss Cham.Since Emhart Glass Örebro has long setup times on some of their machines. This is why we want to identify the current setup process and how the setup process differs between operators. We will also look at whether there are any opportunities for improvement to be made and if they have a standardized way to work. A document that describes how to setup work should be done will also be developed.An excellent tool to shorten the setup time in a production is the SMED method. The philosophy behind SMED is that you should analyze and separate the inner and outer activities. Inner and outer activities mean those activities which can only be performed when the machine is turned off, respectively those activities that can be performed when the machine is in operation.

    In order to standardize the adjustment process so that all operators are working in a similar way it's required that you make a documentation about how the work should be done. Therefore, checklists been developed to the operator. "Checklista - Omställning.xls" is a checklist with the purpose to be able to check which parts of the preparations they have made before the next setup work. It has been designed to be easy to keep track of what parts you have done if you had to work with the machine between the trial or if you quit your shift and leaving parts of the work to the next operator.

    If all of these improvements are implemented, we expect a set-up time reduction of 20.5% which corresponds to about 35min per set-up. By ignoring the running time and only check on the setup times, one can see an improvement of 36.4%.

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  • 32.
    Andersson, Joakim
    et al.
    Örebro University, School of Science and Technology.
    Zurita, Arturo
    Örebro University, School of Science and Technology.
    Reducering av tidsslöseri med hjälp av 5S inom Umicore Autocat Sweden AB2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Umicore is a global company that works with materials. The group has some 80 production plants and around 14400 employees around the world. In Sweden they are at two places, one of which is in Karlskoga. Their name is Umicore Autocat Sweden AB. With their, at the present, 37 employees they manufacture catalysts.

     

    The mission was assigned to us by Umicore Autocat Sweden AB and the purpose of it was to suggest improvements that can be used to try to reduce or eliminate time-wasting that take its shape in the production department. At first it was meant that we would help them to introduce the first three steps of 5S. But because of that we miss estimated the time it would take to do this, we agreed with the company to leave it as suggestion for improvements.

     

    The width of the report consists of the current problems that exist in the company production department. Meanwhile there will be methods and recommendations that will enable improvements to these.

     

    In the implementation of this work interviews, literature studies and all files that the company contributed with from previous work with 5S were used. This is to try to find possible solutions. The result of this is presented as some proposed solutions that can help the company to continue with their quality work. The report also consists of a proposal, with analysis and calculations, of a new layout for the bellows, fixtures and Leister. Some of the information that was used in the calculations we received from the production manager in the company.

     

    We believe that our proposals will work as a tool for the company so they keep improving the quality in their production department by continuing to introduce and implement improvements within 5S. For this purpose it demands that the management ensures that the staff is committed, in this case in 5S.

  • 33.
    Andersson, Mattias
    et al.
    Örebro University, School of Science and Technology.
    Berneke, Anders
    Örebro University, School of Science and Technology.
    Basis and a concept for a Paper machine in a laboratory scale2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis studies paper and what it is made of and different ways to manufacture it in a laboratory scale. It also contains a comparison of different ways to dry tissue and which method that suits a small laboratory tissue machine best.

     A small paper machine was found at Metso in Karlstad that was used as a basis for the concept machine. Since the machine at Karlstad used pressing and a cylinder drying method that involves pressing an alternative method to dry the paper had to be chosen.

    For drying tissue there are several methods like, infrared and through air drying. A comparison was made between those methods to find out which suited the specification best.

    The comparison shows that through air drying is the best drying method for the machine.

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  • 34.
    Andersson, Niklas
    Örebro University, School of Science and Technology.
    Jämförelse av On-line med off-line mätning för ökad processkontroll av kemikaliedoseringar vid kartongtillverkning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    "We challenge conventional packaging for a sustainable future"

    BillerudKorsnäs AB was formed in 2012 and focuses on the paper industry. At the mill in Frövi they create liquid cartonboard for dairy products and packing cartonboard with a production capacity of 470 000 tonnes/year. For making good quality possible proper chemical dosage is required and to guarantee that water tests has to be made. Investing in new measuring equipment will allow steady measurement process. This project is comparing measurement equipment for a steady chemical dosage. In this report comparing between off-line and on-line measurement equipments and routines when measuring different cartonboard layers. This will help the company in there further work with the process for a steady chemical dosage. The result of the comparisons demonstrate a high concentration of titration solution for one layer which contributes to uncertain results. This means that the company have to use a titration solution of lower concentration as well as the present obtain reliable results.

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    Jämförelse mellan Off-och Online-mätning för ökad processkontroll av kemikaliedosering vid kartongtillverkning
  • 35.
    Andersson, Oliver
    Örebro University, School of Science and Technology.
    Utvärdering av småskaligt vattenkraftverk baserat på principen om Arkimedes skruv2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this master thesis is to examine if a small-scale hydro power plant based on Archimedes screw could be a profitable way to power an illuminated outdoor exercise track or corresponding streetlights. A theoretical solution of how the Archimedes screw could work as a hydro power plant was decided on by using a morphological matrix as a by a screening method. Suggestions of parts for the prototype, price calculations and annual energy production of the design. The hydro screw was designed to produce energy that can supply an illuminated exercise track of 4 km or streetlights up to 6 km. To figure out if the hydro screw is economically profitable, the solution was compared to a land-based windmill, were the hydro screw was considered to be profitable if it could match a windmills payback time.  The work resulted in a theoretical design of a small-scale hydro power plant that could work for powering illuminated exercise tracks up to 4 km or streetlights up to 6 km. Results include that the solution cannot match a windmills payback time. On the other hand, hydropower is generally not worse than wind power since Sweden´s hydro powerplants produce almost four times as much energy compered to Sweden´s wind power production. [1] 

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  • 36.
    Andersson, Per-Allan
    Örebro University, Department of Technology.
    Läggartemperaturens inverkan på glödskalet, samt dess inverkan på metoden för avlägsning av glödskalet: litteraturstudie2003Report (Other academic)
  • 37.
    Annika, Strömberg
    Örebro University, School of Science and Technology.
    Effekter av ökad transfer time limit för tandimplantat.2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nobel Biocare is one of the world’s leading companies that produce dental implants. This thesis was executed at the part of the company located in Karlskoga, Sweden.To be sure that the implants manufactured at Nobel Biocare will heal as good as possible when being implanted in a patient, the implant has to go through a coating process where the implants, after a few preparing steps, are going through a salt treatment. This salt treatment will in the end simplify the healing process for the patient. Between every process there is a time limit for how long the implants may rest, a so-called transfer time limit. This time is too short and leads to unnecessary cassations.The purpose of the thesis was to investigate what will happen if the transfer time limit of today increases from eight hours to sixty hours. What will be crucial for the results of the thesis is wether any contamination will occur on the surface of the dental implant or not.To investigate if any possible contamination occurs during the longer transfer time limit the implants were, after a coating process, examined with the help of a laboratry in Great Britain, where XPS analysis of different materials are performed.This thesis has the limitations of examining only the product TiUltra and has only investigated the longer transfer time limit during the coating process of the implants.The result of the thesis is that no contamination occured on the surface, and therefore there now is a basis available for technical documents to increase the transfer time limit from eight hours to sixty hours. This could also be implemented in other areas of the production, where there are similar problems. This thesis could be the base of new test plans for those areas.

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  • 38.
    Antegård, Kristian
    et al.
    Örebro University, School of Science and Technology.
    Mucic, Fuad
    Örebro University, School of Science and Technology.
    CE-märkning av lyftredskap. Processen, användningsområden och dokumentation.2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report is a thesis carried out at BAE Systems Bofors AB in Karlskoga. This report is about exploring and to give suggestions for improvement of the production process and CE-marking of lifting tools. The report also discusses documentation management and documentation requirements for CE marking. What is true at the CE Marking of lifting tools designed for military purposes. The report provides a basic understanding of what purposes CE-marking has and why it is done. Through research and interviews conducted at the company a map of the process for creating and CE marking of lifting tools was created. Using the same method an investigation of the dossier was done. After an analysis of the problem and what emerged during the interviews, the results of the current situation were summarized. One proposed solution was developed that contains suggestions for improvement of the process, suggestions for documentation that should be available and suggestions where documentation should be stored.

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  • 39.
    Arén, Björn
    Örebro University, Department of Technology.
    Die Stresses in the compaction of powders: experiments and analysis2004Conference paper (Refereed)
  • 40.
    Arén, Björn
    Örebro University, Department of Technology.
    Dimensioning of dies for the compaction of shaped PM-parts2003Conference paper (Refereed)
  • 41.
    Arén, Björn
    Örebro University, School of Science and Technology.
    Utveckling - är att se, söka och förverkliga: kursbok i produktutveckling2010 (ed. 1)Book (Other academic)
  • 42.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing from an Industrial Perspective: Product Design, Production and Business Models2018Conference paper (Refereed)
    Abstract [en]

    This paper summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing) from an industrial perspective. The new possibilities to design the part differently simply because the new shape can be produced and which provides benefits with respect to improved material utilization degree, reduced weight, size etc. are addressed in this paper. Different types of generative design concepts such as form synthesis, topology optimization and lattice and surface optimization are exemplified. Low volume production by 3D metal printing is discussed. High volume production by 3D metal printing of manufacturing tools and dies is described.

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/-Market) and the size of the investments required to start the production. The lead time for the production of tools and dies for a new car body is currently about 12 months and needs to be reduced 40% by 2020. The lead time for injection molds for small and large series production must be reduced to 10 days and 4 weeks respectively. Lead time and cost-efficient metallic tools can be provided by 3D metal printing. This paper focuses on tools and dies for the manufacture of sheet metal & plastic components for the engineering, automotive and furniture industries. The paper includes Powder Bed Fusion (PBF). Digitalization through virtual tool & die design and optimization of the tool & die production combined with the PBF´s digital essence provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness.

    3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry in Europe during the coming years.

  • 43.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing from an Industrial Perspective: Product Examples, Production and Business Models2018Conference paper (Refereed)
    Abstract [en]

    This paper summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing) by the so-called Powder Bed Fusion (PBF) from an industrial perspective, particularly in Sweden.

    The new possibilities to design the part differently simply because the new shape can be produced and which provides benefits with respect to improved material utilization degree, reduced weight, size etc. are addressed in this paper.

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/‐Market) and the size of the investments required to start the production. The lead time for the production of tools and dies for a new car body is currently about 12 months and needs to be reduced 40% by 2020. The lead time for injection molds for small and large series production must be reduced to 10 days and 4 weeks respectively. Lead time and cost-efficient metallic tools can be provided by 3D metal printing. This paper focuses on tools and dies for the manufacture of sheet metal & plastic components for the engineering and automotive industries.

    Digitalization through virtual tool & die design and optimization of the tool & die production combined with the PBF´s digital essence provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness.

    3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry during the coming years.

  • 44.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing of Industrial Tools & Dies2019Conference paper (Other academic)
    Abstract [en]

    Tool & die production is an important phase in the development of new components/product models. This phase determines both the lead time (Time-To-Production/-Market) and the size of the investments required to start the production. This paper is focused on Powder Bed Fusion (PBF) and summarizes the current position of 3D metal printing/additive manufacturing (henceforth called 3D metal printing)of industrial tools & dies. It also exhibits the new possibilities to design the tool/die differently simply because the new shape can be produced. Different types of generative design concepts such as form synthesis, topology optimization and lattice and surface optimization are exemplified. The paper exemplifies business cases, the shorter lead times, the associated improved material utilization degree, reduced weight,etc. Low volume production by 3D metal printing is discussed. High volume production by 3D metal printing of manufacturing tools and dies is described. The paper exhibits some examples of digitalization through virtual tool & die design and optimization of the tool& die production and how it provides greater flexibility, better efficiency, tremendous speed, improved sustainability and increased global competitiveness. 3D metal printing is expected to result in several changes in the supplier chain and generate new business models. The present paper describes some of the changes 3D metal printing has led to and is expected to result in within the engineering and automotive industry in Europe during the coming years.

  • 45.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Metal Printing of Production Tools & Dies2018Conference paper (Refereed)
    Abstract [en]

    3D metal printing is of great interest for manufacturing of tools and dies for high volume production. It is possible to accomplish lead time reduction, tool and die weight saving, improved cycle time etc. The presentation deals primarily with Powder Bed Fusion as 3D printing method and describes 3D metal printing of tools & dies both scientifically and from an industrialization perspective. The presentation shows how far we have come in industrialization of 3D metal printing of tools & dies and what needs to be done to include 3D metal printing in the existing industrial systems and infrastructure.

  • 46.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    3D Printing / Additative Manufacturing from Product Creator and Tool Maker Perspectives in the Automotive Industry2016Conference paper (Other academic)
  • 47.
    Asnafi, Nader
    VA Automotive AB, Hässleholm, Sweden .
    3D-printning från produktskapares och verktygsmakares perspektiv2015Conference paper (Other academic)
  • 48.
    Asnafi, Nader
    Volvo Car Components Corporation/Industrial Development Centre, Olofström, Sweden.
    Analytical modelling of tube hydroforming1999In: Thin-walled structures, ISSN 0263-8231, E-ISSN 1879-3223, Vol. 34, no 4, p. 295-330Article in journal (Refereed)
    Abstract [en]

    The automotive industry has shown a growing interest in tube hydroforming during the past years. The advantages of hydroforming (less thinning, a more efficient manufacturing process etc.) can, for instance, be combined with the high strength of extra high strength steels, which are usually less formable, to produce structural automotive components which exhibit lower weight and improved service performance. Design and production of tubular components require knowledge about tube material behaviour and tribological effects during hydroforming and how the hydroforming operation itself should be controlled. These issues are studied analytically in the present paper. Hydroforming consists of free forming and calibration. Only the so-called free forming is treated here. The analytical models constructed in this paper are used to show what the limits are during the free forming, how different material and process parameters influence the loading path and the forming result, and what an experimental investigation into hydroforming should focus on. The present study was a part of a larger investigation, in which finite-element simulations and experiments were also conducted. The results of these simulations and experiments will be accounted for in coming papers.

  • 49.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Application of Laser-based Powder Bed Fusion - Current Possibilities and Constraints for Tooling2021Conference paper (Refereed)
    Abstract [en]

    The current possibilities and constraints for tooling made by the application of Laser-based Powder Bed Fusion (L-PBF) is at the focus of this presentation. Design and manufacturing of production tools & dies for cold and hot working and injection molding are addressed. Solid and topology optimized tools are tested, compared with the conventionally designed and manufactured version of the same tools, and certified. The current possibilities and constraints are addressed from the material, technological and industrial perspectives. The current manufacturing readiness level and the industrialization status of metal additive manufacturing through L-PBF are evaluated.

  • 50.
    Asnafi, Nader
    Örebro University, School of Science and Technology.
    Application of Laser-Based Powder Bed Fusion for Direct Metal Tooling2021In: Metals, ISSN 2075-4701, Vol. 11, no 3, article id 458Article in journal (Refereed)
    Abstract [en]

    The journey of production tools in cold working, hot working, and injection molding from rapid tooling to additive manufacturing (AM) by laser-based powder bed fusion (L-PBF) is described. The current machines and their configurations, tool steel powder materials and their properties, and the L-PBF process parameters for these materials are specified. Examples of production tools designed for and made by L-PBF are described. Efficient design, i.e., high tooling efficiency and performance in operation, should be the primary target in tool design. Topology and lattice structure optimization provide additional benefits. Using efficient design, L-PBF exhibits the greatest potential for tooling in hot working and injection molding. L-PBF yields high tooling costs, but competitive total costs in hot working and injection molding. Larger object sizes that can be made by L-PBF, a larger number of powder metals that are designed for different tooling applications, lower feedstock and L-PBF processing costs, further L-PBF productivity improvement, improved surface roughness through L-PBF, and secured quality are some of the targets for the research and development in the future. A system view, e.g., plants with a high degree of automation and eventually with cyber-physically controlled smart L-PBF inclusive manufacturing systems, is also of great significance.

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