Arbetet handlar om vakuum och hur det kan användas vid tillverkning av smådelar i trä inom möbelsnickeri. Arbetet innehåller grundläggande fakta om vakuum. Tillsammans med en omvärldsanalys bygger det vidare i en utvecklingsprocess av vakuumfästen för tre valda former i trä som är problematiska att bearbeta. 3D-modelleringsprogram tillsammans med 3D-skrivare skapar frihet i framtagningen och visar på att det behövs små medel för avancerad bearbetning. Snickerimaskiner i undersökningen har valts efter svårigheter och säkerhetsfaktorer inför testerna. De har  avgränsats till fyra stycken. Undersökningen och dess tester visar att vakuum kan användas för att bearbeta smådelar samtidigt som det fortfarande finns mycket kvar att undersöka. I den avslutande diskussionen lyfts önskan fram om att arbetet ska inspirera fler att utveckla hantverket och dela sina  kunskaper.

Vatten är ett mångsidigt och föränderligt element. Det kan uppstå i mängder av former, utvecklas och växa till nya mönster. Jag är intresserad av den växande processen av is, där kristallerna bildas. Hur ser den processen ut? Hur kan jag tillämpa dess utveckling genom rumslig gestaltning? Vilka arkitektoniska värden finns i upplevelsen? Hur kan jag bevara min upplevelse? Min upplevelse handlar om att befinna sig innanför och blicka utanför. Det handlar om en tillfällighet. En känsla av upprymdhet och nyfikenhet. Ett spektrum mellan det vackra och tillfälliga ges till verk i det varaktiga. I ett rum av strukturer, samverkat med ljus och reflexioner skapas en ny dimension. En konstellation. En representation av former dolda i ett vinterlandskap. Jag vill genom konkretisering och reformering återskapa min upplevelse genom en fysisk vandring mellan iskristallen och dess mönster som växer fram. Ett mönster i ständig förändring, växer och utvecklas till något nytt. En bevarad upplevelse där ljuset styr det tillfälliga. Ett spektrum av reflexioner, föränderlig genom tid och rum. Innanför til utanför.

Welding is a key process for heavy steel structures, but it is also a weak link in the structure since fatigue fractures in welds are a common cause of failure. This thesis proposes several changes in order to improve the fatigue properties in acost effective way, enabling reduced weight and reduced cost of welded structures. The main idea is to adapt the weld requirements and welding procedures to the load conditions of the weld. This approach ensures that the main focus in the welding process is the critical characteristics of the welds fatigue life properties. The fatigue life critical properties are most often related to the geometrical factors of the weld such as the radius at the weld toe or the penetration in the root. The thesis describes a holistic view of the subject and covers fatigue, weld quality, weld requirements and welding procedures. It becomes evident that the traditional way of working without a direct connection to fatigue is not the best. With an adaptation to the load conditions and fatigue, it is possible to enhance the fatigue life and reduce the welding cost. The main challenge is to connect the welding process, weld requirements and fatigue life properties. It is needed for an optimised welding process of heavy structures subjected to fatigue and toget a predictable fatigue life. Welds optimised for enhanced fatigue life properties are not necessary accepted according to the requirements in a current standard. Several welding procedures are proposed for improving the fatigue life properties of the weld, which indicate a high potential for enhanced fatigue lifeof fillet welds. The idea is to replace the "standard" fillet weld with three different weld types: (i) Welds with deep penetration, (ii) Welds with large weld toe radius and (iii) Welds produced with low cost. Together with customised requirements and reduced over-welding there is a vast potential for reduced weight, reduced cost and increased productivity.The main contribution of this thesis work is the cross-functional studies including design, analysis, production and quality control. This gives a framework for improvements supporting reduced cost and reduced weight of VIII welded structures without reducing the fatigue strength. Many shortcomings have been highlighted to change the welding from a state where welds are done in a way as they "always" have, by tradition, to a more contemporary situation where weld requirements and welding procedures are actively chosen to match the load conditions of the weld. This result in requirements and welding procedures which actually are connected to the fatigue properties as defined by the loading conditions, and where auditors with high probability can say that an accepted weld actually is better than a rejected weld.

Utvecklingen av nya kostnadseffektivare lasertekniker för materialbearbetning har de senaste åren drivit ner marknadspriset för bäddlaserskärning och tar snabbt marknadsandelar från konventionella lasertekniker inom området. PEPAB Produktionspartner AB specialiserar sig inom legoarbeten i tunnplåt och har två stycken koldioxidlasermaskiner, i vilka de utför bäddlaserskärning. En allt tuffare konkurrenssituation har dock gjort att lönsamheten för detta minskar och företaget sökte alternativa användningsområden för maskinerna. Arbetets syfte var därför att söka möjligheter för hur maskinutnyttjandet i PEPAB:s produktion kan utökas. Målet med arbetet var att identifiera och utvärdera alternativa produktionstekniker till den bäddlaserskärning som utförs i företagets laserceller. För att genomföra detta har en metodik för utveckling av maskiners användningsområden tagits fram. Metodiken grundar sig i en teoretisk referensram och består av fyra steg varav det första är en nulägesbeskrivning. I det andra sätts en riktning för utvecklingsarbetet. I steg tre söks utvecklingsmöjligheter för maskinens användningsområden. Dessa analyseras sedan med avseende på hur de påverkar ett antal viktiga faktorer, bland andra kvalitet, säkerhet och ekonomiska konsekvenser. I det fjärde avslutande steget lämnas förslag till företaget. Metodiken visade sig vara ett bra stöd då den gav en tydlig struktur och såg till att fokus låg på rätt saker i rätt ordningsföljd. Genom att tillämpa metodiken på företaget har fyra alternativa produktionstekniker till bäddlaserskärning identifierats. Vidare har ett snabbspår för bäddlaserskärning identifierats, som ett alternativ, med potential att ge lönsammare produktion i maskinerna. Rekommendationer gällande alternativen har överlämnats till företaget. / In recent years, new more cost-effective production techniques in material processing with lasers has been developed. Due to this, more conventional laser techniques such as the carbon dioxide laser has got though competition in laser cutting of thin sheet metal. PEPAB Produktionspartner AB has two laser machines with carbon dioxide laser sources. These machines have been used, almost exclusively, for 2D laser cutting of thin sheet metal. The company is investing in new, more cost-effective equipment for the 2D laser cutting of sheet metal. They are looking for other applications that could make the machines more profitable. The purpose of this thesis was to search for other opportunities to utilize the machines. The aim of the thesis was to identify and evaluate what applications, other than the 2D laser cutting of sheet metal, that could be performed in the company’s two laser cells. To help achieve the aim of the thesis, a work model for development of machine applications was produced. The content and design of the work model is based on a theoretical framework that consists of relevant literature. The four-step work model was then applied at the company where the first step was to describe the current situation. In the second step the company´s intention is identified. Step three focuses on the search for other applications that could be performed in the machines. These are then analyzed with respect to the impact on several factors such as quality, economic consequences and worker safety. In the fourth step, recommendations are given to the company.            The work has resulted in four alternative applications for the future utilization of the machines. Furthermore, another way to create customer benefit has been identified. By forming a fast track for laser cutting and offering customers high delivery service at a higher pricing holds potential to make the machines more profitable. Recommendations regarding each of the alternatives have been given to the company. In addition to this, the work model has proven to work well in the development of machine applications and made sure that focus was on the right things in the right order.

No description available.

The aim of this thesis was to investigate what the relation is between as-quench hardness and final surface hardness for steel beams is, depending on what tempering temperature is used. Also explain how chemistry, dimension and microstructure effects the final mechanical properties of the front axle beam. For this a review of literature concerning the effects was completed.Hardness measurement on the surface was performed on the ends of the beam (bottom and top). This hardness measurement was performed on 6 different front axle articles of the same material (41CrS4) and 2 different front axle articles of another material (40CrMo4). The relation diagram gives an estimation of what type of tempering temperature is needed to achieve the final hardness that is desired. Because the relation was done with some inconsistences it can’t be said to give a perfect answer. The relation diagrams only work for material 41CrS4 and 40CrMo4. For the core hardness test, 2 articles of 41CrS4 and one article of 40CrMo4 was measured on 5 different position on the cross-section, the beams for the respective articles were taken from quenched state and quenched+tempered. The beam dimensions have a significant effect when it comes to cooling down the part and achieve as close to uniform hardness as possible. Even though the Middle point of the I-section sample is one of the closest cores to the surface, it has a softer core compared with the other cores. While there exists hardness difference after quenching between different points in the core they even out after tempering. When comparing the core hardness with the surface hardness it can be said that the surface hardness is not as hard as the core because of decarburization. The microstructure analysis was done on 2 articles of 41CrS4 and one article of 40CrMo4. Samples from the 3 articles is taken from both the as-quenched state and quenched+tempered state. From the optical microscope it could be seen, that the surface of the beams decarbonizes leading to a higher amount of ferrite at the structure and softer surface. Because of this 15 mm into the material is harder than at-surface. Decarburization of the 41CrS4 steels made it so that what should have been a martensite and bainite dominated surface became a ferrite and bainite dominated.To decide the actual amount of retained austenite in the sample an XRD-analysis was performed. The XRD-analysis is done only for one article type of 41CrS4. From the front axle beam three samples of three different locations (bottom, middle, top) was taken for the analysis. For the theoretical calculation of the retained austenite vs the actual amount it can be said that is a very good representation of the total amount of retained austenite in the product. But the theoretical calculation deviates a bit from the actual amount at the top part of the beam. / Syftet med denna avhandling var att undersöka vad relationen är mellan härdat ythårdhet och slut ythårdhet för stålbalkar är, beroende på vilken anlöpnings temperatur som används. Tar också upp hur kemi, dimension och mikrostruktur påverkar de sista mekaniska egenskaperna hos framaxel balken. För detta genomfördes en genomgång av litteraturen om effekterna.Hårdhetsmätning på ytan utfördes på balkens ändar (botten och toppen). Denna hårdhetsmätning utfördes på 6 olika främre axelartiklar av samma material (41CrS4) och 2 olika främre axelartiklar av annat material (40CrMo4). Relationsdiagrammet ger en uppskattning av vilken typ av anlöpningstemperatur som behövs för att uppnå den slutliga hårdheten som önskas. Eftersom förhållandet gjordes med vissa inkonsekvenser kan det inte sägas ge ett perfekt svar. Relationsdiagrammen fungerar endast för material 41CrS4 och 40CrMo4.För kärnhårdhetstestet mättes 2 artiklar av 41CrS4 och en artikel av 40CrMo4 i 5 olika positioner på tvärsnittet, stålen för respektive artiklar togs från härdat tillstånd och härdat + anlöpt. Dimensionerna har en signifikant effekt när det gäller att kyla ner delen och uppnå så nära enhetlig hårdhet som möjligt. Även om mittpunkten i I-sektionsprovet är en av de närmaste kärnorna till ytan, så har det en mjukare kärna jämfört med de andra kärnorna. Det finns hårdhetsskillnad efter härdning mellan de olika punkter men de jämnar ut sig efter anlöpningen. När man jämför kärnhårdheten med ythårdheten kan man säga att ythårdheten inte är så hård på grund av avkolning.Mikrostrukturanalysen gjordes på 2 artiklar av 41CrS4 och en artikel av 40CrMo4. Prover från de 3 artiklarna tas från både härdat tillstånd och härdat + anlöpt tillstånd. Från det optiska mikroskopet kunde man se att stålbalkens yta har blivit utsatt för avkolning vilket leder till en högre mängd ferrit vid strukturen och en mjukare yta. På grund av detta, så är 15 mm in i materialet hårare än vid ytan. Avkolning av 41CrS4 stål gjorde så att det som borde ha varit ett martensit och bainit dominerat yta blev istället ferrit och bainit dominerat.XRD-analysen görs endast för en artikelart av 41CrS4. Från fram axelbalken togs tre prov från tre olika platser (botten, mitten, toppen) för analysen. För att bestämma den verkliga mängden restaustenit i provet utfördes en XRD-analys. För den teoretiska beräkningen av den rest austeniten jämfört med det faktiska beloppet kan man säga det är en mycket bra representation av den totala mängden kvarhållen austenit i produkten. Men den teoretiska beräkningen avviker lite från den faktiska mängden vid stålens övre del.

Additive manufacturing (AM) is a general name used for manufacturing methods which have the capabilities of producing components directly from 3D computeraided design (CAD) data by adding material layer-by-layer until a final componentis achieved. Included here are powder bed technologies, laminated object manufacturing and deposition technologies. The latter technology is used in this study. Laser Metal Powder Deposition (LMPD) is an AM method which builds components by fusing metallic powder together with a metallic substrate, using a laser as energy source. The powder is supplied to the melt-pool, which is created by the laser, through a powder nozzle which can be lateral or coaxial. Both the powder nozzle and laser are mounted on a guiding system, normally a computer numerical control (CNC) machine or a robot. LMPD has lately gained attentionas a manufacturing method which can add features to semi-finished components or as a repair method. LMPD introduce a low heat input compared to conventional arc welding methods and is therefore well suited in, for instance, repair of sensitive parts where too much heating compromises the integrity of the part. The main part of this study has been focused on correlating the main process parameters to effects found in the material which in this project is the superalloy Alloy 718. It has been found that the most influential process parameters are the laser power, scanning speed, powder feeding rate and powder standoff distance.These process parameters have a significant effect on the temperature history ofthe material which, among others, affects the grain structure, phase transformation, and cracking susceptibility of the material. To further understand the effects found in the material, temperature measurements has been conducted using a temperature measurement method developed and evaluated in this project. This method utilizes a thin stainless steel sheet to shield the thermocouple from the laser light. This has proved to reduce the influence of the laser energy absorbed by the thermocouples.

A recent method in aero engine production is to fabricate components from smaller pieces, rather than machining them from large castings. This has made laser beam welding popular, offering high precision with low heat input and distortion, but also high productivity. At the same time, the demand for automation of production has increased, to ensure high quality and consistent results. In turn, the need for sensors to monitor and control the laser welding process is increasing. In laser beam welding without filler material, the gap between the parts to be joined must be narrow. Optical sensors are often used to measure the gap, but with precise machining, it may become so narrow that it is difficult to detect, with the risk of welding in the wrong position. This kind of problems can cause severe welding defects, where the parts are only partially joined without any visible indication. This thesis proposes the use of an inductive sensor with coils on either side of the gap. Inducing currents into the metal, such a sensor can detect even gaps that are not visible. The new feature of the proposal is based on using the complex response of each coil separately to measure the distance and height on both sides of the gap, rather than an imbalance from the absolute voltage of each coil related to gap position. This extra information allows measurement of gap width and misalignment as well as position, and decreases the influence from gap misalignment to the position measurement. The sensor needs to be calibrated with a certain gap width and height alignment. In real use,these will vary, causing the sensor to be less accurate. Using initial estimates ofthe gap parameters from the basic sensor, a model of the response can be used to estimate the measurement error of each coil, which in turn can be used for compensation to improve the measurement of the gap properties.The properties of the new method have been examined experimentally, using a precise traverse mechanism to record single coil responses in a working range around a variable dimension gap, and then using these responses to simulate a two coil probe. In most cases errors in the measurement of weld gap position and dimensions are within 0.1 mm.The probe is designed to be mounted close to the parts to be welded, and will work in a range of about 1 mm to each side and height above the plates. This is an improvement over previous inductive sensors, that needed to be guided to the mid of the gap by a servo mechanism.

Drilling is widely used in manufacturing of products which need holes, for example for fluid channels, screws or pins. Depending on application, workpiece material, cutting parameters and economic considerations, different types of drills are employed. Indexable insert drills are types of drills which facilitate inserts to make holes. These types of drills can make high pitch noises due to vibrations. The focus of this thesis is to investigate the mechanism behind these vibrations in order to help reducing the generated noise in the future designs. Primary investigations show that the main mechanism which results the mentioned noise is regenerative chatter vibrations due to axial and torsional flexibilities. There is a gap in modeling of chatter vibrations in indexable drills where loadings and geometries are asymmetrical and due to torsional vibrations, delay terms are variable. The first step of simulating regenerative chatter vibrations in the drill is to model static cutting forces in a reliable way. In this thesis, a model is proposed which is capable of predicting static cutting forces through segmentation of cutting edges. Since, using this model, forces can be calculated separately on each insert, it is possible to consider differences of inserts in estimationof the cutting loads. The obtained loads are used in the chatter simulation.A model is proposed to simulate chatter vibrations by considering axialand angular deflections and the coupling between them. The resulted model isa system of delay differential equations with variable delays. Variations in timedelays, tool jump-outs and backward motions of inserts have been included inthe proposed time-domain simulation. A set of experiments is conducted toverify the model.

Mitt examensarbete handlar om konstruktioner. Studien handlar om att lyfta blicken och titta på sammansättningar på ett större plan för att hitta nya lösningar på gamla problem.  Jag har i min studie låtit mig inspireras av material och konstruktioner som ligger långt ifrån träindustrin och materialet trä. Genom ett systematiskt insamlande av konstruktioner och vidare analyser har jag, med hjälp av skisser och tester, modifierat dessa till fungerande träkonstruktioner. Det handlar om att skaffa sig en perspektivrikedom som tillåter en att se lösningar till sitt eget fält i sin omvärld, vilket kan leda till nya innovativa träkonstruktioner. Detta är en metod som inte bara fungerar till möbelbranschen utan till många andra fält som kan vinna på att studera lösningar utanför sin egen ram och tradition. Resultatet mynnade ut i en prototyp med en konstruktion som är inspirerad av en stickkontakt/vägguttag. Konstruktionen är intuitiv och demonterbar vilket ska leda till ökad förståelse för konstruktioner hos användaren och en större uppskattning för hantverket. / My thesis I study structures and joints. It is about lifting your eyes and looking at compositions on a larger scale to find new solutions to old problems. I have been inspired by materials and structures that are far away from the wood industry and the material wood. I have systematically collected structures and joints and analysed them. With further sketching and testing, they have been modified to work as wooden joints and structures. It’s about acquiring a ”wealth of perspective” that allows you to see solutions to your own field in your surroundings, which could lead to new innovative wooden structures. This is a method which not only works for the furniture industry but a lot of other fields that could evolve in studying solutions outside their own framework and tradition The result ended up in prototype with a joint inspired from a socket/wall socket. The joint is intuitive and demountable which could lead to increased understanding of structures and joints for the user and a greater appreciation of the craft.