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  • 101.
    Ramesh, Nithin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    ROS based communication system for AGVs: A service oriented architecture (SOA) approach2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project first explored various methods of designing a communication and control system for an AGV. It then implemented a SOA based communication system in ROS on the selected AGV. The ROS package created in the project implemented functions of the Aria and ArNetworking libraries from Adept. The next step of the project implemented the functions of teleoperation, mapping and transfer of maps and navigation from Aria into ROS. The packages built implemented these functions in different ways to test the best method to transfer Aria functions into ROS. A generic set of rules were then formulated that aided the conversion of these functions for users unfamiliar with either of the two packages (ROS and Aria).

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  • 102.
    Repo, Jari
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Wretland, Anders
    GKN Aerospace Engine Systems AB, Trollhättan, Sweden.
    Beno, Tomas
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing.
    Tu, Juei-feng
    University West, Department of Engineering Science, Division of Subtractive and Additive Manufacturing. North Carolina State University, Department of Mechanical and Aerospace Engineering, Raleigh, North Carolina, United States.
    Detectability of various machining conditions by using internal encoder signals2016In: The 7th International Swedish Production Symposium, SPS16, Conference Proceedings: 25th – 27th of October 2016, Lund: Swedish Production Academy , 2016, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Automated Tool Condition Monitoring (TCM) often relies on additional sensors sensitive to tool wear to achieve robust machining processes. The need of additional sensors could impede the implementation of tool monitoring systems in industry due to the cost and retrofitting difficulties. This paper has investigated the use of existing position encoder signals to monitor a special face turning process with constant feed per revolution and machining speed. A signal processing method by converting encoder signals into a complex-valued form and a new vibration signature extraction method based on phase function were developed to analyze the encoder signals in the frequency domain. The cumulative spectrum indicated that the spectral energy would shift from the lower to the higher frequency band with increasing cutting load. The embedded vibration signatures extracted from the encoder signals provided additional detectability of the machining condition with distinguishable spectral modes. This paper confirms the sensitivity of the encoder signals and more signatures could be extracted for tool wear detection in the future work.

  • 103.
    Rydholm, Jonas
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Implementering av underhållssystem vid en tillverkande industri.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company in the study was experiencing a problem when it comes to dealing with maintenance-work. The processes for bug tracking and ordering of spare parts is time con-suming and involves work from several different people. Most of all maintenance work performed is unplanned and a functioning follow-up work is missing.

    The purpose of the thesis was to help improving the company's efficiency by optimizing the maintenance work. This was achieved by a proposal for a maintenance system and vari-ous approaches to improve the maintenance work.

    During the project a maintenance log book was been designed in Excel. The log book is used to log all maintenance activities that occur in the production. These logs are the basis for most of the calculations carried out during the project.

    The calculations aimed to identify where in the process most errors occur and what the na-ture of those errors are. To demonstrate the potential of a maintenance system the profit opportunities that can be achieved through the implementation of a maintenance system and new working methods were calculated.

    The study resulted in a proposal for a maintenance system that suited the company's needs, situation and problems. In addition to the introduction of a maintenance system, it was also clear that the company needs to reduce the amount of unplanned downtime. To achieve this it is important to involve the operators with maintenance work and they shall perform all the works of the simpler kind. The maintenance department can then, thanks to the re-leased time, focus on finding the root causes of problems and perform scheduled mainte-nance to reduce the amount of unplanned maintenance.

    Improving the maintenance work and introduce Total Productive Maintenance (TPM) is a time consuming process that might go on for years. In order to facilitate the work and re-duce the risk of falling back into old habits an implementation model was designed for the TPM-work. The model is intended as a future work for the company to facilitate the work of reaching even higher efficiency.

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  • 104.
    Sandström, Kristina
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Johansson, Kristina
    University West, Department of Social and Behavioural Studies, Psychology and organization studies.
    A small scaled study on pro and cons with the educational design of Co-operative Education2016In: Engineering 4 Society 2016 Raising awareness for the societal role of engineering. Leuven, Belgium 15 - 16 September 2016: Proceedings,, Leuven, 2016, p. 87-90Conference paper (Refereed)
    Abstract [en]

    For 25 years University West has been the leading university in Sweden when it comes to Work Integrated Learning (WIL) and Co-operative Education (Co-op). This paper describes mainly the sustainable and mutual benefit between the companies and the students. How ever, Co-operative education is a model that does not only benefit the students – it's described as a win-win situation for all partners. This study will provide some explanatory examples from using Co-operative Education as a networking and bridging model between the students, the universities and industry. This model aims to enhance life long learning in the work place. It also provides an opportunity for the university staff to catch up the needs from the industry in their ongoing work – such as new competency development modules, research and development etc. The paper uses an educational design that describes the benefits for participants, as well as it provides an opportunity to scrutinise the possible obstacles that lie within this model. A questionnaire has been distributed to the persons that have the overall responsibility for introducing the student at the company, students that were in their first Co-op placement and students that had finished their second Co-op placement. The results were analysed with a content analysis focusing on text material.

  • 105.
    Schelin, Erik
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Larsson, Filip
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Effektivisering av materialflödet med hjälp av  materialförflyttningskoncept på Bodycote i Angered2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bodycote in Angered works with heat treatment and surface treatment of steel components. Bodycote aims to keep up with the industrial development and are therefore exploring opportunities to automate parts of the workshop. The company is a processing company where deliveries consist of products that will return to the supplier. Bodycote has identified the time the operators put on transporting goods in the material flow as unnecessarily large, in the next step, they want to explore the possibility of streamlining the material flow. The objective with this study is to investigate the concepts that are relevant to freeing time for operators regarding the material transfer. The remaining concepts are investigated to ultimately be tested in an investment assessment, the idea of which is to serve as a basis for decisions regarding the introduction of a new material transfer concept. This study follows the DMAIC methodology, which is a method to ensure that the problem is correctly understood, that the problem solving is based on facts, the root causes are identified and that effective solutions remains. For the collection of results-based data, methods such as value flow analysis, spreadsheets, subdivisions in to product families etc. are used. After the concepts were assessed in terms of criteria and weighting, which were set according to Bodycote's prerequisites and requirements, two concepts were kept that were passed on to investment assessment, the concepts were automatic trucks and product trains. Some concepts that are generated, which do not meet the criteria equally well, may need to be used as a partial solution when introducing a new material transfer concept, especially the layout improvement proposal.   

  • 106.
    Severinsson, Markus
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Perstedt, Ida
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Lindström, Martin
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Development of a Titanium Outlet Guide Vane with Honeycomb Core2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GKN Aerospace Sweden develops and manufactures engine components for the aerospace industry. One of these components is the outlet guide vane (OGV) which, in a set of several, constitutes the mechanical connection between the core structure and fan case of the Fan statics. The aerodynamic application of the OGV is to redirect the airflow from the fan.

    An important goal for the aerospace industry is to develop fuel efficient engines with as little carbon dioxide emissions as possible. A weight reduction of the engine is an approach to reach the above mentioned goal. The weight can be reduced by component design or by using a material with a high strength-to-weight ratio.

    During this bachelor thesis, the scope was to develop a titanium outlet guide vane with honeycomb core through concept maturation, welding evaluation and strength analysis. The material properties and behavior of the honeycomb panel was investigated through drop weight testing, modal analysis and high cycle fatigue.

    The results are summarized in a proposed final concept, referred to as the honeycomb OGV. A comparison between the price of the honeycomb OGV and the present market value of an OGV subjected to lowest loading shows that the honeycomb OGV is currently more expensive. However, the relatively high strength combined with the comparatively high cost makes the honeycomb OGV suitable for placement in the part of the Fan statics subjected to highest loading.

    The welding processes evaluation showed that resistance welding and laser beam welding are two joining methods for joining of the honeycomb OGV.

    The honeycomb panels have shown a remarkable high strength throughout the practical tests and can therefore be considered as an interesting alternative in lightweight and high strength designs.

  • 107.
    Shaholia, Kewal
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Obstacle avoidance in AGVs: Utilizing Ultrasonic sensors2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, there are industries that utilize AGVs to transport goods and materials from one location to another. For smaller scale industries it is costly to have a custom made AGV for their manufacturing unit, so they modify the shape of an AGV to accommodate the necessity of carrying and transporting goods. When the shape of an AGV is modified the built-in sensors will not detect the change in shape of the AGV. Hence, there is a risk that the AGV may collide with objects. Also in some AGVs floor sensors are missing to detect the presence of floor/no floor in front of the AGV, which can be a hazardous situation as there are chances of the AGV falling off from the surface. An example of such an AGV is the Patrolbot which can travel around in an industrial premise wirelessly, but needs addition of such sensors to avoid collisions with the modified structure. A Patrolbot has been used in this thesis work and ultrasonic sensors are utilised for obstacle detection with a modified structure and a built-in laser scanner is studied for mapping purpose. The results of this master thesis was that the ultrasonic sensors were tested under various conditions and results were derived. To obtain the same level of results every time it is required to maintain the conditions on which the ultrasonic sensors rely.

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  • 108.
    Singh, Vivek
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Tuovinen, Johnny
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptutveckling av säkra snabbfästen för grävskopor2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis work was carried out for a firm that manufactures and sells attachments and buckets for excavators. The work is performed as a product development project at University West. Since there have been a number of accidents where buckets of the type produced by the company have fallen from quick couplers, it is now required to review the design of the quick coupler. The project started with a study of why accidents with dropped buckets occurred. It turned out that all the accidents studied had been due to that the wedge lock was closed the wrong way. After the initial literature study, the work to establish customer requirements began. Problems were listed and broken down into subproblems. After this step solutions were generated to the subproblems by using brainstorming, Triz effect database and Triz 40 principles. Through patent and competitive analysis a basis for concept generation was created, which started with brainstorming. When concept generation was done then concept screening and concept scoring was used for selecting a concept.

    An FMECA was performed on today's quick coupler before the new construction was drawn in CAD and then an FMECA was performed on the new construction. The FMECA showed that many of the risks found on the original design were eliminated in the new design. Finally the new design was tested using FEM analysis where it was compared with a corresponding simulation of the original design. Thereafter an analysis was performed as a simulation of the forces operating in different directions. The simulations showed that the new design is at least as good as the original design and no major changes needed to be made. The result was a quick coupler similar to the original design, but has wedge locks at both ends of the quick coupler and an indicator that shows if the coupler has the correct position towards the bucket before locking the wedge lock. In the report result chapter the final selection of the concept is presented in more detail.The approach of Ulrich and Eppingers description of product development has worked well. It is a structured model to follow that deliver a result based on customer requirements.

  • 109.
    Sjöstedt, Jacob
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Magnusson, Daniel
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konceptutveckling av ljud- och vibrationsreducering för scrollkompressor i en elektrisk bil2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete har utförts under tio veckor på ÅF Automotive i Trollhättan med syftet att reducera det hörbara ljudet för passagerarna i en elektrisk bil. Huvudproblemet är att kompressorn i klimatanläggningen genererar luftburet ljud och vibrationer vilket leder till en försämrad komfort för passagerarna. ÅF Automotive ska köpa in en ny kompressor och önskar en kravspecifikation innehållande ljudkällorna i en scrollkompressor samt riktlinjer för hur effekterna från dessa kan reduceras. Denna kravspecifikation ska senare användas som beslutsunderlag till förhandlingen. Koncept i form av komplement till scrollkompressorn ska utvecklas som reducerar luftburet ljud och vibrationer från varje identifierad ljudkälla.För att genomföra arbetet på ett systematiskt sätt har metoder och verktyg lämpade för konceptutveckling använts. Ljudkällorna i scrollkompressorn identifierades genom att utföra observationer, intervjuer och litteraturstudier. En kravspecifikation på de identifierade ljudkällorna upprättades därefter. Genom att tillämpa en generisk produktutvecklingsprocess utvecklades flera koncept för att reducera ljud och vibrationer från de identifierade ljudkällorna. För att finna de bästa koncepten utfördes konceptval innefattande multiröstning,beslutsmatriser och mer djupgående analyser vilka behandlar risk för patentintrång, miljöpåverkan, ljudreduceringsförmåga, monterbarhet, säkerhet samt kostnad. Fyra koncept; fjädrar, gummibussningar, hårt skal och mjukt skal valdes då de reducerar ljudet i passagerarutrymmet och presterade väl under den djupgående analysen och är därför värda att vidareutveckla. Hur mycket ljud de kommer att reducera har inte specificerats. Detär nu upp till ÅF Automotive att göra ett val över vilka koncept som de vill vidareutveckla. Koncepten är fortfarande på en generell nivå och måste anpassas specifikt till den scrollkompressor som väljs att köpas in. Koncepten har endast utvecklats för att reducera ljud och vibrationer och det finns fortfarande osäkerheter som kommer behöva behandlas i framtiden.

  • 110.
    Stridh, Peter
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konstruktion av mekaniskt lyftdon2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is the result of a thesis work and describes the development of a standardized gripping device. The gripper had to lift and let go of the object only by lifting it up or place it down. It had to be completely mechanical and handle a load up to 75 kg. The requirement was to produce gripper device with laser cut parts with as small manufacturing time as possible and that the components would not cost more than 800 kr.

    At first various types of grippers were studied at the company and later on the studies continued on the Internet. At the same time simple sketches were made on different concepts. Some of the sketches were made as models in CAD. A concept was chosen and further developed. One of the improvements was that the gripping arms was given parallel movement instead of radial and with a stronger gear compared with a regular scissors gripping device. The correct dimensions for the components were calculated and a final CAD model was created. Out of model the drawings were made and a prototype was manufactured.

    The prototype was assembled and tested and the gripper lifted the object as it should. The locking mechanism opened and closed as it should. The gripper was tested to meet two times the safety with no plastic deformation. A load test was made where the prototype managed to take a load over 150 kg which is approved. After that the prototype was tested, there were a few changes to improve the function and to reduce the price. The cost of the components was 920 SEK but compared to the company's other lifting devices it was not very expensive.

    The conclusion of the work was that the functional requirements were met and that the gripper works.

  • 111.
    Svennungsson, Anton
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Optimering av fyllnadsgraden i containrar lastade med laminatrullar2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Mölnlycke Health Care is a world-leading provider of single use surgical and wound care products for costumers, healthcare professionals and patients. The company has over 7 500 employees. Mölnlycke Health Care is active in over 90 countries and has manufacturing facilities in 9 different countries. When manufacturing a product, for example the laminate reels, different parts of the production are outspread on several factories. For the flow of the laminate reels, it starts in Belgium and will finish in Thailand. This means that there are a number of transports and logistic issues impacting the production flow. The laminate reels are loaded into containers before they are shipped to Thailand. The problem with the transportation is that the company is estimating that the fill rate of the containers is approximately 50 percent, which is inefficient and waste of resources and money. The purpose of the thesis is to identify the factors that result in a low filling rate and also suggest solutions to increase the fill rate.

    To gather information about fill rate and logistics literature studies have been done. Factors that affect the fill rate have been used as the basis when information about the current situation has been gathered and analyzed. Underlying factors to the low fill rate in the container has been ranked with a FMEA as a tool based on how much the specific factor affects the fill rate. The FMEA tool was then the basis when solutions to increase the fill rate were developed by using concept combinations table and concept sieving matrix.

    The thesis resulted in ten factors that affect the fill rate, also four ideas on solutions on how to increase the fill rate where engineered. Whish are labeled I, F, G and B.

    I – Optimizes the fill rate with 34 %, saving 2.6 million Swedish crones per year in transportation costs and reduces CO2 emissions by 161 208 kg per year.

    F – Optimizes the fill rate with 43,2 %, saving 3,3 million Swedish crones per year in transportation costs and reduces CO2 emissions by 205 777 kg per year.

    G – Optimizes the fill rate with 38,5 %, saving 2.9 million Swedish crones per year in transportation costs and reduces CO2 emissions by 179 544 kg per year.

    B – Optimizes the fill rate with 39,26 %, saving 3 million Swedish crones per year in transportation costs and reduces CO2 emissions by 136 138 kg per year.

  • 112.
    Svensson, Thomas
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Åhs, Christian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Kartläggning av kritiska maskiners utrustningseffektivitet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is comprised of an investigation of equipment effectiveness at the company Produce AB (fictitious name) at two machine cells, Alfa, which consists of four millers and Beta, which consists of four lathes. The company is a subcontractor of metal products to three different business areas and consists today of 100 employees. By measuring the actual time the machinery process goods for the customer the company have identified low machine utility as a problem in the production. With this investigation, they therefore want to identify the causes of this problem in order to improve the business and become more competitive. The approach for this investigation is based on the methodology within Six Sigma where the DMAIC model has been used. Quantitative data collection occurred during ten days with the use of an operator template, where duration and cause of machine downtime was noted. Qualitatively, unstructured, semi-structured and fully structured interviews have been used to analyze the root causes for machine downtime that was identified following the quantitative data collection. The main part of the theoretical framework for this thesis includes total productive maintenance and overall equipment efficiency, which was used to map and calculate the current state of the equipment efficiency. Other theoretical frameworks are Lean, material- and production planning, resource utility and variations. These theories were used to analyze the result and give suggestions for improvement. The calculated equipment efficiency varies between both the cells and the machines within the cells. In the Alfa-cell, values vary between 52 and 80 per cent and in the Beta-cell between 37 and 57 per cent. The significant causes for machine downtime were identified as lack of personnel, long set-up times, machinery waiting for operators, differences in processing time between cycles and machine breakdowns. From this, suggestions for improvement were developed. The suggestions included employment of addition personnel, reduction of set-up times, introduction of an Andon-system and elimination of processing time differences. In general, the authors of this thesis can see that the company has a will to improve, but the work with improvements has been suffering since the production is behind, compared to what the customer demands. A lack of resources and short term-thinking are therefore considered two of the things that most affect the company's possibilities to maintain a competitive business.

  • 113.
    Sylvén, Julius
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Evaluation of heavy duty diesel engine coolant pumps2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this time of environmental awareness and corporate social responsibility, it is vital for companies to offer environmentally friendly products or services in order for the companies to be competitive. Being one of the largest truck manufacturers in the world, Volvo Trucks is obligated to follow this trend. The biggest drawback with a truck in an environmental perspective is its pollutants and carbon dioxide emissions. A major variable when reducing emissions is the fuel consumption. Trucks are used for transport and run day and night, often for very long distances. It is safe to say that even a very small reduction in fuel consumption has a major impact on both the fuel economy and the environmental impact over the truck's lifetime.

    This report consists of a comparison made of a fixed coolant pump and a 2-speed clutch pump. A fully variable clutch pump was also meant to be tested but was not, due to limited resources. The aim was to determine the best alternative to proceed with regarding fuel economy, which is the ultimate goal for Volvo Trucks.

    The test results are not reliable because of major mechanical errors due to flaws in the test equipment used. This report works as a basis for continued research regarding clutch performance. However, from the results given it is clear that a controllable coolant pump clutch is the right field of study to continue researching since it has great power saving possibilities.

  • 114.
    Söderblom, Robin
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Jonsson, Staffan
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Feasibility study for implementation of automotive measuring method in aerospace industry2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis comprises an investigation in order to find possibilities to implement the method used in the automotive industry to automatically generate a collision free measurement program within the aircraft components manufacturer. The purpose with the study was to compare and analyse the different methods used to generate measurement programs at GKN Aerospace Engine Systems in Trollhättan, National Electric Vehicle Sweden (NEVS) and Volvo Cars Corporations (VCC).The study was conducted through meetings, observations and questionnaires with staff from the geometry assurance engineering (GAE) departments and measurement departments in each company. By mapping the virtual GAE process started from concept development in CAD to the measurement phase in which components are measured in coordinated measuring machines (CMM), a chain of activities was analysed.NEVS and VCC are today using RD&T and IPS to generate optimized CMM programs in which a time efficient measurement path can be generated. This method was compared with the current approach at GKN Aerospace where they use one supplier for offline CMM programming (OLP) software solutions and CMMs. They are thereby working in a closed system where the OLP communicates with the CMM by supplier specific methods. The automobile manufacturer NEVS and VCC, in contrast, uses a DMIS protocol which is an ISO and ANSI standard.The study shows that an implementation of the software used by the Swedish automobile manufacture NEVS and VCC at GKN Aerospace in Trollhättan, may not have any significant improvements regarding time savings and thereby no economic benefits. However, the approach for generating an optimized measurement program in RD&T and IPS may have major improvements in other facilities within the aerospace industry which has also resulted in an instruction manual to be used for potential implementation.

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  • 115.
    Tallian, Mattias
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Konstruktion av växel till arborrstång med vandrande huvud2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Most industries are dependent on large machines to carry out their activities. If these machines brake down or for some other reason are taken out of service it quickly leads to large consequential costs in the form of delays, etc. It is therefore a top priority to avoid these shutdowns, and if they arise quickly fix the problem that caused it. The problem with all types of maintenance and repair work on these machines is that they are too large to move to a workshop that has the necessary resources to fix the problem. To perform this type of maintenance and repair work must thus the resources required to address the problems moved to the place the machine is located.

    The equipment required for these types of jobs must often be tailored to fit each individual assignment. The designer is challenged to effectively develop a solution that takes all specific circumstances into account.

    Metalock Engineering Sweden AB is working with this type of repair work and has designed a line boring machine for line boring of bolt holes in large shaft couplings. Line boring is a process used to machine existing holes to precise dimension. Typical applications where line boring is required is these shaft couplings, but also bearing seats and machine leads requires precise holes with respect to the diameter and cylindricity. The machine that Metalock has constructed uses a mechanical gear drive for generating the power required for the power feed of the cutting head. This gear unit was developed under a very limited period of time. This resulted in an undeveloped gear unit with major operating problems that presents a direct safety hazard to the machine operator.

    The goal of this project was to construct a new gear unit that meet all the requirements regarding function- and safety. The work was carried out through a product development process and a study of the theory of mechanical transmissions, gears and bearings. Solution concepts where developed, and one concept was chosen for further development. From the chosen concept a gear unit which met all the specifications was constructed. The components of the gear unit were modeled using the CAD-program Autodesk Inventor. The components were then assembled in the CAD-program and used to carry out a verification of the gearbox kinematics.

  • 116.
    Tano, Ingrid
    et al.
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Nylen, Per
    University West, Department of Engineering Science.
    Wigren, Jan
    Gupta, Mohit Kumar
    University West, Department of Engineering Science, Division of Manufacturing Processes.
    Curry, Nicholas
    University West, Department of Engineering Science, Division of Mechanical Engineering.
    Relationships between Coating Microstructure and Thermal Conductivity in Thermal Barrier Coatings – A modelling Approach2010In: International Thermal Spray Conference and Exposition, ITCS Singapore 2010: 3-5 May 2010,  Singapore, Düsseldorft: DVS Media , 2010, p. 66-72Conference paper (Refereed)
    Abstract [en]

    Fundamental understanding of relationships between coating microstructure and thermal conductivity is important to be able to understand the influence of coating defects, such as delaminations and pores, on heat insulation in thermal barrier coatings. Object-Oriented Finite element analysis (OOF) has recently been shown as an effective tool for evaluating thermo-mechanical material behaviour, because of this method's capability to incorporate the inherent material microstructure as an input to the model. In this work, this method was combined with multi-variate statistical modelling. The statistical model was used for screening and tentative relationship building and the finite element model was thereafter used for verification of the statistical modelling results. Characterisation of the coatings included microstructure, porosity and crack content and thermal conductivity measurements. A range of coating architectures was investigated including High purity Yttria stabilised Zirconia, Dysprosia stabilised Zirconia and Dysprosia stabilised Zirconia with porosity former. Evaluation of the thermal conductivity was conducted using the Laser Flash Technique. The microstructures were examined both on as-sprayed samples as well as on heat treated samples. The feasibility of the combined two modelling approaches, including their capability to establish relationships between coating microstructure and thermal conductivity, is discussed.

  • 117.
    Tysse, Simon
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Utveckling av torkningsprocess för produkter av PEPP2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fordonsbranschen står i nuläget inför många utmaningar att identifiera lösningar med hög prestanda för att klara av konkurrens i en global marknad. Cellplaster är en grupp material som är attraktiv för fordonsbranschen då de möter många av de höga krav som ställs. Exempel på sådana cellplaster är: expanderad polystyren (EPS), expanderad polyetylen (EPE) och expanderad polypropylene (EPP). Materialen produceras till ett granulat som sedan kan formgjutas med vattenånga. Slutresultatet är produkter med hög prestanda i stöttålighet, energiabsorbering och en mängd övriga egenskaper. Bewi Automotive formgjuter komponenter i EPP till Volvo Car Corporation, SCANIA trucks och ett flertal underleverantörer. Komponenter som tillverkas är stötfångare, utfyllandsdetaljer och emballage. Under 2016–2017 har företaget genomgått en expansionsfas där ett flertal produktfamiljer introducerats i verksamheten. En produktfamilj tillverkas av en ny variant av materialet EPP kallad Porous expanderad polypropylene (PEPP); materialgranulatet har håligheter vilket efter formgjutning skapar luftfickor i den färdiga produkten. Luftfickorna bidrar till att produkten blir ljudisolerande. Ett problem som uppstått med det nya materialet är att vid formgjutning med vattenånga stannar mycket vatten kvar i produkternas luftfickor.

    Syftet med rapporten var att antingen identifiera ett sätt att förebygga vatteninnehållet i PEPP-produkter, eller skapa en lösning för att hantera problemet. Examensarbetet avgränsades till att endast behandla tre PEPP-produkter; endast konceptuella lösningar skulle identifieras. Mål med examensarbetet var att framställa en kravspecifikation. DMAICmodellen valdes för att identifiera en lösning på problemet. En intervju med företagets kvalitetschef gjordes för att definiera problemet. Mätningar av produkternas vikt gjordes för att identifiera mängden vatten som stannar kvar i PEPP-produkterna. En intervju med representant från råvarutillverkaren JSP Arpro genomfördes för att analysera problemet och identifiera möjliga lösningar. Torkningstiden mättes i en konvektionsugn i en temperatur på 80 grader Celsius. En strukturerad produktionsutvecklingsprocess användes för att identifiera en lösning som hanterar problemet. Företagets nuläge och de tre utvalda produkterna analyserades. Värde-och flödesanalyser genomfördes och en kravspecifikation upprättades. Därefter utfördes en konceptgenerering och konceptval. Det slutliga konceptet utvärderades med en process-FMEA och kostnader uppskattades. Viktiga resultat är att det krävs en behandling i 360 minuter i en konvektionsugn för att avdunsta vattnet i PEPPprodukter. Ingen gångbar förebyggande lösning kunde identifieras. Det slutliga konceptet är en konvektionsugn som är konstruerad för att kunna existera i fabrikens nuvarande layout, och har kapacitet att klara av full produktionstakt av PEPP-produkter. Potentiella effektiviseringar kan göras genom användning av andra torkningsmetoder såsom strålning.

  • 118.
    Westerlund, Christian
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Benchmark study: Sill concepts for electric vehicles2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The market for electric vehicles is expanding and the car manufacturer want to store as much energy as possible in the car. However, if the battery cells in the vehicle are damaged there is a risk that the battery could start a fire or explode. To avoid that the battery cells are damaged during a crash scenario, it is important to minimize the intrusion in the body structure. At the same time the car manufacturers do not want to increase the weight or manufacturing cost of the car more than necessary. The purpose of this study is to perform a benchmark study which compares the crashworthiness of different sill concepts used by various automotive companies.

    The different sill concepts that are being benchmarked in this thesis are Tesla Model S, BMW I3, Mercedes S-Class and Volkswagen E-golf. To be able to compare the sill structures from these different cars, some modifications must be done to their original geometry. A standardized cross section is created and the material thickness is adjusted until all concepts has the same mass. When the geometries have been designed, a nonlinear finite element calculation is performed to evaluate the crashworthiness of each sill concept. The finite element analysis is based on the standardized load case: side pole impact. The result shows that the concept inspired by Tesla Model S has the best performance when considering intrusion. However, if the concept inspired by Tesla Model S does not get enough support from the floor structure, it will lose its ability to absorb energy after a certain amount of time. And therefore, the BMW I3 concept could be a good alternative to the Model S concept if it is not possible to provide this additional support.

  • 119.
    William, Omar
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Development of waste sorting system2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor’s thesis is a mechanical engineering project done in cooperation with Swedish Innovators. The aim of this project has been to develop and design a waste sorting system in order to enhance the waste sorting process.

    After the first meeting with the client, it was understood that the product needs to be developed in aspects like design and functionality to make it suited for marketing. A number of demands was also established, in order to ensure that the redesigned product will fulfil its purpose.

    The project started with a product definition process that included studying existing products, search for relevant articles and a survey research to gather customer needs and ideas. After defining the product and gathering all possible information regarding the subject, a number of customer requirements were gathered.

    A number of concepts were generated according to the customer requirements and four of them was chosen by the client and the student for further development. And in order to choose the best concept of the four, selection matrices were used.

    The result of the project was one concept that satisfied almost all the requirements. The concept contains three main parts: a frame, a drawer and a container. The concept fulfils almost all the established demands by the client like ergonomic design and easy to install and assemble. After assembling the concept, the user should have a product that contains seven parts: one frame, two drawers and four containers, and the product should enhance the process of waste sorting with its practicality and ergonomic design.

  • 120.
    Zouity, Amina
    University West, Department of Engineering Science, Division of Mechanical Engineering and Natural Sciences.
    Parameterstudie om lasersvetsning av en nickelbaslegering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The bachelor's thesis has been performed at Siemens Industrial Turbomachinery AB in Trollhättan, Sweden. The aim of this bachelor's thesis was to identify problem in a welding process in order to improve the weld quality. Based on statistical experiment four factors were evaluated with DOE method and ten experiments in material 2 mm Hastelloy X was performed with Siemens fiber laser (3D Prima Laserdyne 795). The factors weld speed,shield gas, focal point and laser power were the four welding parameters that varied in the experiment, in order to evaluate the factor effects on pores and joint geometry in the welds. Plane test plates were created to the experiments and brainstorming with the personal at Siemens in order to identify which factors to choose for the experiments. To evaluate pores and joint geometry the test plates was x-rayed, sectioned, polished and etched. Joint geometry was measured and photographed with microscope. Statistical analyze was performed with Minitab to estimate the factors effect on pores and joint geometry.Problem in the weld process was identified based on the ten experiments, which werepores and critical dimensions for the joint geometry. A conjunction for the pores and joint geometry was identified. The conjunction was if pores occur in the weld joint the joint geometry affects negatively too, but it's not statistical verified. The weld process have been identified to be unstable based on the statistical analyze that been performed. The weld process needs to be further evaluated, to identify confounding factors, which affect the stability of the welding process. One of the ten experiments was closest to the criterias for approved weld joint. The experiment that was closest to the criteria's for approved weldjoint is recommended for further work to Siemens. The welding parameters that are recommended to be evaluated further are laser power and the interaction factor welding speed and shielding gas, which can have a significant impact on the pores and joint geometry based on the statistical analysis performed by Minitab.

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