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  • 1.
    Aarenstrup, Filip
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Effektivisering av informationsflödet mellan säljkontoren i orderprocessen inom Höganäs AB2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Höganäs AB is one of Sweden’s oldest companies established in 1797, the company have 1900 employees today and is one of the leading producers of metal powder in the world. From the subsidiary Höganäs Sweden AB 300,000 tonnes of metal powder was dispatched 2015. The material was sent to Höganäs customers that mainly consist of component manufacturers in the automotive, wood and other manufacturing industry.

    The purpose of this thesis is to suggest a new operational working process that will increase the efficiency of the order handling process. Throughout the investigation the present state of the process has been outlined and identified at Höganäs Sweden AB.

    Höganäs AB’s order handling process consists of many operations and interfaces that are involved to secure high delivery performance to the customers. The complexity of the process increases due to this and demands an effective communication between involved interfaces. The order handling process may vary depending on factors such as delivery terms, payment terms, transport, product, country, customs clearance and quantity. The variation of these factors makes it difficult to implement a standardized approach.

    It is valuable to Höganäs AB to streamline the process. The data recorded in the business system from the customer order is an important basis for production-, dispatch- and planning departments. The recorded data can be obtained earlier if high quality conditions are created that can increase the delivery performance and affect customer relationships positively.

    With support from the collected theory and the study that contains qualitative and quantitative primary data from Höganäs Sweden AB a new working process have been formed that excels the efficiency in the process. The new approach streamlines the overall process time by 40 percent and the overall lead time with 32 percent. In addition to the increased efficiency the number of information exchanges in the process was reduced significantly.

  • 2.
    Abdallah, Karl
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Sisodia, Raoul
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kvalitetsproblem med inre dörrpanel2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work has been conducted at International Automotive Components Group in Torslanda, Sweden. The company produces door panels, instrument panels, consoles and cockpits for the automotive industry.

    During the production of door panels, defects such as pressure marks and scratches emerge which results in scrap and rework. The objective of the thesis work was to identify the causes of pressure marks and scratches and also to suggest measures to reduce the amount of scrap and rework on door panels.

    Through observations, interviews and experiments, several causes leading to pressure marks and scratches on door panels were identified. Small pieces of plastics on fixtures, the operator's rough handling and specific process steps are the main causes that result in pressure marks and scratches.

    Pressure marks and scratches emerge at several places on the door panels during the production. To reduce the amount of pressure marks and scratches both short-term and long-term measures were suggested. Some of the measures are:

    •  Use vacuum cleaners at some stations
    •  Add padding on unpadded areas and edges
    •  Make new instructions that emphasize to keep production stations clean and to avoid rough handling
    •  Introduce workshops to engage operators
  • 3.
    Abdallah, Kristian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Pedestrian Protection System: Hood lift study2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Every year approximately 400 000 pedestrians are killed worldwide in road related injuries where children and elderly are the most exposed age groups. The design of the front-end of a vehicle and the structural stiffness have a significant influence on the kinematics and injury risks of the pedestrian body. To create a clearance between the rigid hood structure and the hood, the hood is lifted. A lifted hood does however not provide protection over the cowl, windscreen and A-pillar areas.

    This study is performed at Autoliv Sverige AB and the purpose is to examine how fast the hood can be lifted 100 mm using a pedestrian protection airbag. The airbag give an extended protection while covering the cowl, windscreen and A-pillar areas.

    A concept generation session was performed where modifications of the current pedestrian protection airbag, for a faster hood lift, were proposed. The generated concepts proceeded to a concept screening session where the Autoliv evaluation matrix was used.

    The selected concepts went further to static testing where the performance of each concept was tested. The performance include the lift time of 100 mm for the most rearward section of the hood, positioning of the cushion and pressure distribution. The tests were carried out in a room temperature environment.

    To conclude the thesis work, one winning concept could not be obtained. Two concepts excelled themselves from all the concepts and a difference in the performances between these two concepts could not be found.

    In this thesis no calculations on costs such as material costs and manufacturing costs has been made. This can be the major aspect on choosing one winning concept but due to the fact that there is no time for a cost analysis in this thesis, the PPA development team will take over.

  • 4.
    Abdullah, Loai
    et al.
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Hansson, Robert
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Dimensionering av skruvförband i spannmålselevator2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 5.
    Abdulmohsin, Haider
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Prediction of cutting forces for second layer removal in metal cutting process2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Machining processes studies and theories can be referred back to the beginnings of machine age, but recent developments in information technologies (Computers, processors, etc.) make it easier for the researchers to predict material behaviour during different machining processes.

    Machining is not a simple process to analyse due to the amount of variables affecting on it, in this study the author is trying to analyse and explain the forces acting on a AISI 1045 workpiece during the removal of material’s second layer using FEM, one of the challenging problems was to re implement the forces resulted from the first layer removal in the new cutting process to give the study more reliable output to compare with the actual results obtained previously the procedure used to reach this is explained in chapter 3, there are many software used to define FEM analysis each has its benefits and limitations, LS-DYNA which is used in this study is one of those software "it is capable of simulating nonlinear problems involving large deformations, sophisticated material models and complex contact conditions".

    As well as LS-DYNA, HyperMesh and Ls-prepost are used in this study to mesh the tools and workpiece, and pre-set the material parameters respectively.

  • 6.
    Abebe Mengistu, Bemnet
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Internal sensor measurement to reduce the need of coordinate measuring machines2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis presents the approach of determining the machining  errors on a five axis CNC machine using sensors already fitted in the machine to extract valuable data up on process called CITE(CNC Integrity Tracing Equipment) system and measuring the machined workpiece geometry using CMM(Coordinate measurement machine). CITE measurement system is the data acquisition hardware and software system developed by University West for collecting position information from encoders of a machine tool. The collected information could then be used to assess the quality and adjustment of a machine tool, CNC programs and the CNC control parameters. The aim of this study is to examine the roundness and concentricity detection capacity of the CITE system by conducting different milling methods and a turning process. In an example cutting of a workpiece, the CITE measurement system was used for recording the machining process. After that, radial error, centre point deviation and circle roundness errors, analysed using MATLAB based on collected CNC tool movement data. CMM measurement used to verify the results obtained from the CITE measurement system. The investigation conducted on the small circles shows that the CITE measurement system have capability of identifying radial errors in different method of millings (slot, up and down). Centre point deviation and roundness errors measured by the CITE system doesn`t show significant differences between milling methods as seen on CMM measurement.

  • 7.
    Abrahamsson, Sten
    et al.
    Gotland University.
    Tosteby, Jonas
    University West, Department of Engineering Science, Division of Process and Product Development.
    Isaksson, Raine
    Gotland University.
    Integrated Management Systems: testing a model for integration2011In: 14th Toulon-Verona Conference: Organizational Excellence in Service. Conference Proceedings / [ed] Jacques Martin & Claudio Baccarani., Alicante: University of Alicante , 2011, p. 22-35Conference paper (Refereed)
    Abstract [en]

    Management systems are widely used for creating order, minimising risks and for assuring performance. Management systems are in many occasions integrated since this has been found to be beneficial. In this paper a model for a fully integrated management system (IMS) based on the three axes of level, extent and scope of integration is tested for relevance. The studied system permits the integration of all relevant process dimensions. The research is only in a pilot stage, but the initial results are promising and indicate that there are advantages in using the process view as a base for identifying critical aspects to be managed. A review of the current situation for system integration is studied and the model is subjected to some tests using Sweden as a case. The background study shows that system integration still is limited, especially when comparing with a fully integrated IMS. The feedback from the organisations interviewed is positive and supports continued work with development of the model.

  • 8.
    Agardsson, Edvin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Leijer, Malin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Verktyg för identifiering av tidsåtgång för materialhantering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Autoliv Sverige AB är ett företag som ligger i Vårgårda och tillverkar airbagar, gasgeneratorer samt elektronik till radarsystem. I framtiden finns planer för att expandera produktionen men i dagsläget vet företaget inte hur mycket resurser som går åt för materialflödet till de olika produktionslinorna. För att ta reda på hur mycket personella resurser som behövs både i befintligt materialflöde och i framtida produktionslinor vill företaget undersöka systemet som matar fram material till produktionen. För att ta fram ett verktyg som gör detta används aktionsforskning som huvudmetodik. Aktionsforskning utgör en iterativ process som består av observationer, framtagning av lösningsförslag och utvärdering av lösningsförslag. Observationerna genomfördes i samband med datainsamlingen där Kanbanrundan undersöktes, definierades och mätetal togs fram. Detta för att få en grundförståelse för vad innehållet i verktyget skulle vara.Nästa steg i processen var framtagning av lösningförslag, vilka skapades med hjälp av benchmarking av interna dokument och informationen som samlats från observationerna. En konceptmodell per person skapades och ett koncept valdes sedan ut som utgångspunkt för fortsatt utveckling av verktyget. Modellen blev sedan granskad respektive förbättrad av medlemmarna och handledaren på företaget i en iterativ process.När modellen ansågs klar verifierades det mot verkligheten och den insamlade datan. Verktyget validerades sedan genom att en anställd på Logistikavdelningen fick testa det. Utöver utvecklandet av verktyget och insamlingen av datan utfördes en benchmarking både internt på företaget och externt på ett annat företag för att studera olika materialhanteringsprocesser.I analysen diskuterades för- och nackdelar med olika val och iakttagelser som gjorts, både i arbetssättet för detta examensarbete och dess olika delar men också för materialhanterarens arbetssätt och instruktioner. Resultatet av arbetet blev ett verktyg som uppfyller de krav som formulerades i början av arbetet. Utöver verktyget upptäcktes även ett flertal förbättringsmöjligheter kring materialflödet och produktionen.

  • 9.
    Agell, Ulrica
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Robotmanipulering med Leap Motion: För små och medelstora företag2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    On-line programming of industrial robots is time consuming and requires experience in robot programming. Due to this fact, small and medium sized enterprises are reserved about the implementation of robots in production. Ongoing research in the field is focused on finding more intuitive interfaces and methods for programming to make the interaction with robots more natural and intuitive. This master thesis presents a method for manipulation of industrial robots utilizing an external device other than the traditional teach pendant. The base of the method is a PC application which handles the program logic and the communication between an external device and an ABB robot. The program logic is designed to be modular in order to allow customization of the method, both in terms of its functions and the type of external device that is used for the method.

    Since gestures are one of the most common forms of communication between humans, it is interesting to investigate gestures for the purpose to make manipulation of industrial robots more intuitive. Therefore, a Leap Motion controller is presented as an example of an external device which could be used as an alternative to the teach pendant. The Leap Motion controller is specialised on hand and finger position tracking with both good absolute accuracy and precision. Further, its associated Software Development Kit (SDK) has the capabilities which are required to enable implementation of a teach pendants most fundamental functionalities. Results obtained by a user test show that the developed application is both easy and fast to use but has poor robustness.

  • 10.
    Agic, Adnan
    et al.
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. Seco Tools AB,Fagersta, Sweden.
    Gutnichenko, O.
    Division of Production and Materials Engineering, Lund University, Sweden.
    Eynian, Mahdi
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Ståhl, J-E
    Division of Production and Materials Engineering, Lund University, Sweden.
    Influence of cutting edge geometry on force build-up process in intermittent turning2016In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 46, p. 364-367Article in journal (Refereed)
    Abstract [en]

    In the intermittent turning and milling processes, during the entry phase the cutting edges are subjected to high impact loads that can give rise to dynamical and strength issues which in general cause tool life reduction. In this study the effect of geometrical features of the cutting tool on the force generation during the entry phase is investigated. Cutting forces are measured by a stiff dynamometer at a high sampling frequency. In addition, the chip load area is analyzed and related to the measured cutting force. The results show that micro-geometrical features, in particular the protection chamfer, significantly affect the force generation during the entry phase.

  • 11.
    Ahlgren, Rikard
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Dörrich, Wictor
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Processutveckling av förslagsverksamheten vid GKN Aerospace Sweden2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The business world is constantly subject to intense competition that requires continuous development of products, personnel and operations within the company. The development towards a better state comes at the expense of strict requirements in job descriptions where continuous improvement is part of the working role of individuals. In order to link the continuous improvement of the business well-being, there is a need of structured work for improvement in ways of a well-functioning suggestion scheme. Suggestion schemes main purpose is to utilize the experience and knowledge of all employees by encouraging individuals' skills and creativity, which will contribute with innovative and competitive suggestions. Personnel is a resource that covers particular knowledge that no other company can copy; therefore it should be utilized to the maximum extent possible.

    The aim of the project is to identify and specify improvement measures for the suggestion scheme at GKN Aerospace Sweden AB in Trollhättan. The work consisted of an initial literature review, which included direct and indirect factors effecting the continuous improvement with linkage to the proposed suggestion scheme. In order to concretize the theoretical framework of the tools main purpose for the continuous improvement, a theoretical and a practical benchmarking was utilized. The company's current suggestion scheme was mapped and analyzed, and a foundation for future improvements was established.GKN Aerospace Sweden is part of the GKN Group, which operates in more than 30 countries around the world and employs about 50 000 individuals. The company manufactures components for aircraft and rocket engines, as well as service and maintenance. In the current situation GKN Aerospace manages a suggestion scheme that depends entirely on an internal IT system and has an average lead time of 43 weeks until a decision is made. The reward system for received suggestions is an economic reimbursement calculated through a complex formula. The entire suggestion scheme process is extensive and includes several loops for conducting the evaluation of suggestions.

    The thesis resulted in improvement propositions based on studies and situation analysis, but differs from the expected target to improve and develop the current system. The problem that arose was that the current system does not support the company's expectations for the suggestion scheme process. It resulted in a completely new system with associated procedures and reward guidelines were developed to create incentives and higher motivation for the submission of suggestions for improvement. The improvement propositions resulted in: dedicated time for improvements, group-based activities for continuous improvements, start-up meetings, new process, basis for the development of a new IT system, economic and symbolic rewards.Date: 2015-

  • 12.
    Alagic, Almira
    et al.
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Balint, Norbert
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Marknadsanpassning av kabelskopa2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Excavating buckets are tools that construction machines use for excavation, demolition or moving different sorts of soils. Buckets are exposed to harsh environments there for ex-ample weather and the soil material that wears and strains the tool. To minimize wear and increase the tool's efficiency, can the material for the bucket be suited for the environment in which the tool is used.

    The aim of the project is to help the company to increase their exports to the EU. The goal is to produce a cable bucket adapted for the Dutch market, which is based on the product's current weight, material composition, performance and cost.

    Based on the company's needs the focus of this project is to adapt a cable bucket to the conditions and the market in the Netherlands. In order to implement a market expansion the company also needs to get information about market conditions, circumstances and customer requirements.

    In the end of the project a cable bucket considered to be adapted for the Dutch market were proposed. The comparison between the new bucket and the existing bucket resulted in a lighter and cheaper bucket where the material choices are based on the most common in the Netherlands and the bucket performs as its competitors.

  • 13.
    Alfredsson, Jonas
    University West, Department of Engineering Science, Division of Industrial Engineering and Management, Electrical- and Mechanical Engineering.
    Framtagning av kravspecifikation och affärsmodell för fjärrdiagnostisering av lyftlösning2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In collaboration with Binar Quick-Lift Systems AB, a product development project has been carried out at the University West in Trollhättan. Binar Quick-Lift Systems AB manufactures and develops lifting solutions for loads up to 300 kg and is an affiliate of the Binary Group, where operations are conducted in two primary areas: Industrial Solutions and First Responder Technology.

    The vision for most companies is to develop and given the current trend of the Internet of Things, Binar wanted to see how a wireless communication solution can integrate with the company's existing lifting solutions. The goal of this mission was to establish a requirement specification and a business model for wireless diagnostics of their lifting solution, based on customer needs and the company's basic requirements.

    The introduction of the project consisted of a preliminary study which included information gathering and interviews with stakeholders and experts. A market investigation was performed in parallel with the interviews where a function and competitor analysis were conducted to obtain relevant customer data as well as an understanding of the market. The requirement specification was established using collected information in the preliminary study and the business model was generated from the preliminary study as well as the customer and base requirements.

    The result was a requirement specification with mainly subjective requirements as well as a business model with a basic contract offer for the sale of the wireless solution.

  • 14.
    Allgurén, Olivia
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Patama, Sanna
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Securing the just-in-time delivery for the after-market: Study at Volvo car customer service2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis has been performed at Volvo Car Customer Service in Gothenburg, Sweden. The output from the study will support Volvo to secure the Just-In-Time delivery of referrals for the after-market. The scope was limited to referrals from pre-planned orders, which occurs when there is no availability in the distribution centre where the orders were placed.

    Volvo's main warehouse in Europe is the Central Distribution Centre, which process referrals. The warehouse had an ongoing organisational change during this study. The concern was that the change would not lead to optimal conditions for processing referrals for different markets. It was therefore important to preserve the market knowledge in order to maintain a reliable referral service.

    A qualitative study was used and the information was gathered primarily through semi-structured interviews. Literature was studied both initially and continuously through the study. Analyse of the literature, current situation and data collection generated ideas for possible ways of securing the referral process and improvements. Benchmarking and Workshop was also performed in order to obtain further ideas.

    The result of this study was an information material containing information about all concerned markets, overview of referral flow and information regarding how the Central Distribution Centre needs to print referrals. The proposals suggested for future work were explained in long- and short-term. The short-term suggestions include use of the developed material in order to preserve the knowledge along with providing correct working conditions. For long-term suggestions focus has been on how to reduce or remove the printing problem. For future work Volvo Car Customer Service should consider these proposals in order to secure and improve the referral service.

  • 15.
    Alwaeli, Laith
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Sjukvårdens behov av kurser inom verksamhetsutveckling2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 16.
    Anderberg, Staffan
    University West, Department of Engineering Science, Division of Production Engineering.
    A study of process planning for metal cutting2009Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Process planning as a function for competitiveness is often neglected. However, as an intermediary between product development and manufacturing, it holds a key function in transforming product specifications and requirements into a producible process plan. Demands and requirements should be met concurrently as manufacturing costs and lead times are minimised. The focus of this thesis is the act of process planning, where the use of better methodologies, computer-aids and performance measurements are essential parts. Since process planning has the function of transforming demands and requirements, changing customer and regulative requirements are vital to regard. Since environmentally benign products and production increases in importance, the research presented in this thesis includes a CNC machining cost model, which relates machining costs to energy consumption.  The presented results in this thesis are based on quantitative and qualitative studies in the metal working industry.

     

    This thesis has contributed to an enhanced understanding of process planning to achieve better performance and important areas for improvements. Despite a 50 year history of computerised process planning aids, few of these are used in the industry, where manual process planning activities are more common. Process planning aids should be developed around the process planner so that non-value adding activities, such as information management and documentation are minimised in order to allow more resources for value adding activities, such as decision making. This thesis presents a study of systematic process planning in relation to perceived efficiency. This correlation could however not be verified, which opens up for further studies of other possible explanations for process planning efficiency. Process planning improvements in the industry are difficult to make, since there is little focus on process planning activities and limited knowledge about actual performance hereof. This means that measures taken regarding process planning development are difficult to verify.

  • 17.
    Anderberg, Staffan
    University West, Department of Engineering Science, Division of Process and Product Development.
    Methods for improving performance of process planning for CNC machining: an approach based on surveys and analytical models2012Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Process planning as an enabler of competiveness is often overlooked, but being one of the principal function in the product realisation flow it holds a key role by combining both product and production requirements into a production concept with respect to the current manufacturing system. As such the capability of process planning to a large extent dictates production cost, lead times, product quality etc. With the introduction of new demands on production, such as environmental impact and process capability, process planning must be able to manage these demands effectively. Accordingly, it is vital to study the effects that up-coming demands have on the act of process planning. The research methods employed in this work include surveys (questionnaires and interviews), industrial case studies and experiments to provide data for models developed. The main finding of this research is that there is a lack of quantified process planning performance knowledge in the industry, which leads to verification problems as to whether changes that are made render anticipated effects. Results of surveys also indicated a low level of digitalisation of product data and limited use of computer aids (CAM, feature-based CAM and PLM) in Swedish industry based on 144 companies' response. A concept to improve process planning performance through operation classification based on process capability indices (Cp/Cpk) was suggested. The role of process planning in designing cost efficient and energy efficient machining operations has been maintained throughout the thesis by showing how tool selection and machining parameters selection influences the possibilities to achieve these objectives. This work has also showed that no inherent contradictions appear to exist between achieving cost efficient and energy efficient machining operations. This thesis has contributed to an enhanced understanding of how process planning improvements can be achieved through a holistic perspective of the process planning function, where both technical and methodological aids are included. It is however essential to understand the current situation of the process planning organisation, its internal/external relations, level of digitalisation, competency level etc. before major changes of the process planning function are undertaken in order to be successful.

  • 18.
    Anderberg, Staffan
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Pejryd, Lars
    3Production Technology Centre, Innovatum AB.
    A survey of metal working companies’ readiness for process planning performance measurements2009In: IEEE International Conference on Industrial Engineering and Engineering Management, IEEM 8-11 sep, 2009, Hong-Kong, 2009, p. 1910-1914Conference paper (Refereed)
    Abstract [en]

    The paper presents an investigation regarding the potential and the readiness for implementing performance indicators and performance measurement systems of the process planning work for metal working companies. The paper is based on a questionnaire survey distributed to process planners in the Swedish metal working industry. The main outcome of the investigation is a foundation for understanding the implementation of performance measures of the process planning work for CNC machining. The survey revealed a few strengths and short comings in the studied companies.

  • 19.
    Anderberg, Staffan
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Pejryd, Lars
    Production Technology Centre, Innovatum AB.
    CNC machining process planning productivity – a qualitative survey2009In: Proceedings of The International 3'rd Swedish Production Symposium, SPS 09, 2009, p. 228-235Conference paper (Refereed)
    Abstract [en]

    Process planning is the link between design and manufacturing and consequently an important function, since it influences many of the company objectives. However, many companies have little knowledge about their process planning function and the efficiency is thus not optimal. The paper focuses on the automation level of process planning as a mean to improve process planning efficiency. Six CNC machining companies was interviewed and accordingly analysed through a five dimensional automation level model to understand their process planning work. The main findings are that the automation level is low and concurrent engineering is lacking in many of the investigated companies.

  • 20.
    Anderberg, Staffan
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Pejryd, Lars
    University West, Department of Engineering Science, Division of Production Engineering.
    Production preparation methodology in Swedish metal working industry - a State of the Art investigation2008In: Swedish Production Symposium, Stockholm 18-20 November 2008. Proceedings: The Swedish Production Academy's annual conference / [ed] Bengt Lindberg och Johan Stahre, Stockholm: The Swedish Production Academy , 2008, p. 443-450Conference paper (Other academic)
    Abstract [en]

    This article presents a brief state of the art in the Swedish metal working industry regarding the production preparation process for the machine centre. The article is based on a relationship model from which a questionnaire was developed. The model incorporates the perceived preparation process efficiency, the amount of systematic preparation work, in relation to the companies’ premises as possible causes. The investigation is based on a general hypothesis that a more systematic approach in the preparation process leads to higher preparation process efficiency. This hypothesis was supplemented by two more hypotheses and additional analyses to create an understanding of the situation. The main finding in this investigation is that there appear to be no relationship between increased  ystematic preparation work and perception of higher preparation efficiency. The investigation also indicates that many metal working companies have little knowledge about the performance of their preparation process and that there is an efficiency improvement potential of nearly 30%.

  • 21.
    Anderberg, Staffan
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Kara, Sami
    University of New South Wales.
    Energy and cost efficiency in CNC machining2009In: The 7th CIRP Conference on Sustainable Manufacturing: Chennai, India, December 2-4, 2009., 2009Conference paper (Refereed)
    Abstract [en]

    General cost for CNC machining and the associated energy cost are set in the context of making economic and environmental improvements. This creates an incentive for manufacturing companies to investigate the energy efficiency of manufacturing processes. The paper presents a costing model, based on machining experiments. The model is accompanied with an industry based case to estimate the cost savings. The results show that substantial cost savings with respect to energy efficiency is unlikely, since energy costs in CNC machining comprises a small cost component. However significant cost savings can be achieved if the production output is increased as a consequence from higher material removal rates due to optimised machining parameters.

  • 22.
    Anderberg, Staffan
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    Kara, Sami
    University of New South Wales.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Production Engineering.
    Impact of energy efficiency on computernumerically controlled machining2010In: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 224, no B4, p. 531-541Article in journal (Refereed)
    Abstract [en]

    Increasing environmental demands from governmental bodies and customers stress the importance of companies improving their environmental performance. The research presented here shows that productivity and cost efficiency improvements can be achieved alongside energy savings in a computer numerically controlled machining environment. This improves the profitability of the companies, but also leads them towards more sustainable and environmentally aware manufacturing; the relationship between machining parameters, machining costs, and energy consumption is evaluated. From this perspective, it is important that production planners etc. understand the methodological possibilities for improvements in cost and energy efficiency. The current research is based on a machining cost model and experiments where energy consumption and tool wear were monitored.

  • 23.
    Andersson, Daniel
    University West, Department of Engineering Science, Divison of Natural Sciences, Surveying and Mechanical Engineering.
    Design of a high precision and highdamping joint2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis was to design a joint that combines high precision and high damping. A possible application for the joint is to reduce vibrations in machine tools or workpieces during metal cutting processes. The goal was that the joint would clamp a test steel beam with the maximum repeatable referencing precision of 0,05 mm and increase the dynamic stiffness in the beam by 200 %. The increase in dynamic stiffness should also be achieved with less than 20 % reduction in static stiffness in the beam. Five different joint types were evaluated from which pinned joint was selected. Damping is accomplished by incorporating a thin layer of viscoelastic material in the joining surfaces and three pins are used for precision alignment between the surfaces.

    The joint was tested with the finite element method to evaluate the damping property before it was manufactured. After manufacturing, an experimental modal test was performed using an impact hammer to evaluate the damping capability. The precision of the joint was measured in a CNC machine. Experiments showed that the repeatable referencing precision of the joint is inside 0,05 mm. The dynamic stiffness in the beam is increased by 180 % with 23 % decrease in static stiffness. 

  • 24.
    Andersson, Daniel
    University West, Department of Engineering Science.
    The performance of an iced aircraft wing2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this thesis work has been to develop and manufacture an ice layer which was to be mounted on the tip of a scaled down wing model. The iced wing should be tested in a wind tunnel and aerodynamic comparisons should be made to the same wing without ice.The development of the ice was carried out as a modified product development process. The main differences are that there is no costumer and that the actual shape and functions of the product are more or less predetermined. The challenge was to find the best way to create the ice layer and how to mount it to the wing without damaging it or covering any pressure sensors. Product development methods such as pros and cons lists and prototypes were used to solve problems before printing the plastic ice layer in a rapid prototyping machine.Wind tunnel experiments were then conducted on the wing with and without the manufactured ice. Raw data from the wind tunnel were processed and lift and drag coefficients were calculated using mathematical equations. Finally, conclusions were drawn by comparing the results from the wind tunnel tests with theory, other works as well as CFD simulations.The ice layer was successfully manufactured and it met the target specifications. The aerodynamic performance of an iced aircraft wing proved to be considerably worse compared to a blank wing. The maximum achievable lift force decreased by 22% and an increased drag force will require more thrust from the airplane.

  • 25.
    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.

  • 26.
    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.

  • 27.
    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.

  • 28.
    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.   

  • 29.
    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.

  • 30.
    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.

  • 31.
    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)
  • 32.
    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.

  • 33.
    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.

  • 34.
    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)
  • 35.
    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.

  • 36.
    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)
  • 37.
    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.

  • 38. Batungwanayo, Guillaume
    et al.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Automation Systems.
    Ericsson, Mikael
    University West, Department of Engineering Science, Division of Electrical and Automation Engineering.
    Weld Joint Tracking System in an Automatic Inspection Cell by Using Emissivity Variation2014In: Proceedings of the 6th International Swedish Production Symposium 2014 / [ed] Stahre, Johan, Johansson, Björn & Björkman, Mats, 2014, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Thermography has proven to be a suitable nondestructive testing method for automatic crack inspection of welds. However automatic weld inspection raises challenges. E.g. the position of the weld might not be exactly as the predefined weld seam, and a weld joint tracking system is needed. To reduce the number of equipment used, a solution is presented in this papers. The infrared camera in the thermography system is a carrier of information of the weld path. This is used for the weld joint tracking system. It is shown that the weld joint tracker is fast enough for an on-line automatic inspection.

  • 39.
    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.

  • 40.
    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.

  • 41.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Production Engineering.
    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.

  • 42.
    Beno, Tomas
    et al.
    University West, Department of Technology, Mathematics and Computer Science, Division for Mechanical Engineering.
    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 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)
  • 43.
    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, 2009Conference paper (Other academic)
  • 44.
    Beno, Tomas
    et al.
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    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.

  • 45.
    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.

  • 46.
    Bergström, Per
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Luleå, Sweden.
    Fergusson, Michael
    Xtura AB, Kungsbacka, Sweden.
    Folkesson, Patrik
    Xtura AB, Kungsbacka, Sweden.
    Runnemalm, Anna
    University West, Department of Engineering Science, Division of Production System.
    Ottosson, Mattias
    University West, Department of Engineering Science, Division of Production System.
    Andersson, Alf
    Chalmers University of Technology, Department of Product and Production Development, Gothenburg, Sweden.
    Sjödahl, Mikael
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Luleå, Sweden.
    Automatic in-line inspection of shape based on photogrammetry2016In: The 7th International Swedish Production Symposium, SPS16, Conference Proceedings: 25th – 27th of October 2016, Lund: Swedish Production Academy , 2016, p. 1-9Conference paper (Refereed)
    Abstract [en]

    We are describing a fully automatic in-line shape inspection system for controlling the shape of moving objects on a conveyor belt. The shapes of the objects are measured using a full-field optical shape measurement method based on photogrammetry. The photogrammetry system consists of four cameras, a flash, and a triggering device. When an object to be measured arrives at a given position relative to the system, the flash and cameras are synchronously triggered to capture images of the moving object.From the captured images a point-cloud representing the measured shape is created. The point-cloud is then aligned to a CAD-model, which defines the nominal shape of the measured object, using a best-fit method and a feature-based alignment method. Deviations between the point-cloud and the CAD-model are computed giving the output of the inspection process. The computational time to create a point-cloud from the captured images is about 30 seconds and the computational time for the comparison with the CAD-model is about ten milliseconds. We report on recent progress with the shape inspection system.

  • 47.
    Bhoje, Sourabh
    University West, Department of Engineering Science, Research Enviroment Production Technology West.
    Termisk cykling provuppställning konstruktion och provning av TBCs för dieselmotorapplikation2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thermal barrier coatings (TBCs) thermally insulate the substrate from high temperature exposure. This work attempted to simulate real engine thermal cyclic conditions by designing a test method to evaluate the thermal cyclic fatigue (TCF) performance of different coatings applied inside exhaust manifold of a diesel engine. The coatings investigated in this work comprised of two plasmas-sprayed TBCs (conventional 8YSZ and nanostructured 8YSZ) and one bond coat (NiCoCrAlY). Additionally, these coatings were exposed to isothermal testing and their oxidation behavior was evaluated.   All the coatings along with only substrate were exposed to temperature around 525°C for 150 cycles in thermal cyclic testing carried out on Scania’s heavy-duty diesel engine. For isothermal testing, all coatings along with only substrate material were exposed to 650°C and 750°C for 168 hours respectively. Microstructural analysis by SEM/EDS was carried out to compare the microstructural evolution of the tested coatings with the as sprayed TBCs. In the case of thermal cyclic test, all coatings showed no failure and no TGO growth up to 150 cycles. In the EDS analysis for isothermally tested coatings, oxidation of the substrate at bond coat- substrate interface instead of TGO growth was observed. Bond coat showed lowest oxide layer thickness at 650°C and 750°C followed by conventional YSZ and then nanostructured YSZ. But, conventional YSZ showed microcracks in top coat near top coat- bond coat interface after isothermal testing. Thermal cyclic and isothermal exposure test results showed that bond coated substrate and nanostructured YSZ have the potential to be implemented inside the real manifold.   

  • 48.
    Birgersson, Eric
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kunéll, David
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of logistical capacity and future storage needs at the Technical Material Analysis department of Volvo Cars2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has been performed at Volvo Car Corporation in Gothenburg, Sweden. Volvo’s Technical Material Analysis department, TMA, has experienced large increases in incoming material quantities since 2015. The objective of the study was to establish a well-founded proposal for improvement that can make the logistical situation at TMA sustainable in a long-term perspective. TMA is a business within Volvo’s Warranty department. Its main purpose is to store material on behalf of other departments within Volvo, and to perform analyses on warranty claims from dealers. In order to collect relevant information, several conventional methods have been used. Semistructured and unstructured interviews were used when studying the business structures and learning about the effects of different departments on TMA. Data collection was performed via archive studies, collecting historical data within Volvo’s internal computer system. Brainstorming and a workshop were used together with TMA staff in order to capture advantages and disadvantages concerning the potential improvement proposals. After the evaluation of a number of concepts, only one remained: to move the business to new facilities. This is considered the only proposal that can establish a long-term sustainable logistical situation for TMA. The other concepts that were considered can potentially solve the current logistical situation, but certainly not tomorrow’s, due to the expected increases in incoming material quantities. The study’s conclusion is thus that the TMA business must be moved to larger facilities, in order to be able to fully maintain its business. The improvements that did not meet the long-term objectives are still considered valuable for the business. They are: Higher inventory turnover and New storage layout with new pallet racks. The implementation of these can establish a better work environment due to decreased amounts of storage, shorter lead times, higher work efficiency and a better over-all control over the storage business.   

  • 49.
    Blom, Johanna
    et al.
    University West, Department of Engineering Science.
    Öster, Carl-Johan
    University West, Department of Engineering Science.
    Åtkomststudie för robotiserad svetsning av flygmotordetalj2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis was to investigate if the robotized welding method FSW (Friction Stir Welding) could be applied for joining a rotating structure in an aero engine at Volvo Aero Corporation. FSW is expected to introduce less defects than today’s welding methods and could therefore be suitable for critical aero components. The material is the nickel based alloy Inconel 718, however a material experimentation is outside the scope of this report.The main goal of this study is to verify if the ESAB ROSIO robot based FSW-system has a suitable work space to be able to weld the rotating structure, and if the welding tool has accessibility to the joints. The FSW-process needs a rigid fixture, and a number of fix-ture concepts are presented based on a proposed weld sequence. A final fixture design is proposed, which requires a new design of the structure.The accessibility studies were performed in the robot simulations software Robot Stu-dio. This showed that the robot was unable to weld the proposed model in all areas in the original design. If the robot and the rotating structure can be redesigned the access will be achieved as shown in Robot Studio simulations.In order to be implemented in real production a number of further actions need to be taken and the result of this study can be a basis for these.

  • 50.
    Blomgren, Anton
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptförslag på tunnelkonsol med mugghållare och förvaring2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The background to this project is that Volvo Cars AB wants to give the customer more opportunities to store things in their cars. Today, the customer brings many different objects into their cars, for example cups, bottles and cell phones. The customer would like to have the ability to store these things in a practical and easily accessible way.

    Volvo Cars AB wanted new ideas for the centre stack with focus on the cup holder and storage facilities. The centre stack is the component that are located between the driver's seat and passenger seat of the car where the armrest and gear lever are. The concepts that were developed shall make the centre stack into a more efficient and smarter way to store things. The project was to develop a cup holder that can be used as a cup holder and at the same time as a storage space, a dual functional cup holder. It was also included in the task to find other storage facilities that can improve the centre stack.

    In this project a product development process has been used to produce concepts for the centre stack. By analysing the assignment and the use of brainstorming about 70 ideas was produced. They were reduced to 24 through a discussion with the supervisor at Volvo. Then a discussions was conducted with engineers at Volvo from the interior department, that resulted in eleven concepts remained to be developed further. From these eleven concepts three end concepts were chosen with the help of a decision matrix.

    The three end concepts were two dual functional cup holders and one bottle holder. All these end concepts are easy to apply to the centre stack and are also easy for the customer to use.

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