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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Produktionsanpassning av värmelisten Stayhot

Radovic, Nebojsa January 2006 (has links)
<p>Abstract</p><p>My task was to prepare the already designed heating list “Stayhot” for manufacturing.</p><p>I started with drawing the whole list in the CAD-program. It became obvious that some of the designed components had to be changed to work in practice.</p><p>A turnable reflector couldn’t be combined with the isolation. The suggested light emitting diodes wouldn’t give enough light, so I cut them out and the problem with light remains to be solved. The old grating had many rods and I changed that to a grating with fewer rods to make it easier to clean. The hanging-up of the grating was also changed.</p><p>The lower ceasing was changed to be closed towards the reflector to avoid filth and damp.</p><p>The reflector had a different shape. From having been square it became oval to follow the shape of the above ceasing and have a more even isolation. It also opens up to the possibility to use two heating elements. The heating-source should have been changed to be warmer, but as the new elements didn’t come until my work was almost finished, I couldn’t use it.</p>
12

Slutmontage av ventilavledare PEXLIM Stark / Final Assembly of Surge Arrester PEXLIM Strong

Stenström, Erik January 2008 (has links)
<p> </p><p>På ABB i Ludvika tillverkar man en mängd produkter för högspänningsanläggningar. En av dessa produkter är ventilavledare. Ventilavledaren är en säkerhetsapparat som ska skydda övrig utrustning mot förekommande överspänningar. Ventilavledarna som tillverkas i Ludvika är gjorda för system från 52kV upp till 800kV, vilket är den högsta spänningen som används i världen idag. Idag finns två varianter av ventilavledare en med porslinisolant och en med polymerisolant. På ABB ser man att kunderna mer och mer eftersträvar polymeravledare.</p><p>Polymeravledare har p.g.a. mekaniska begränsningar inte kunnat användas i system med högre spänning än ca. 245kV. För att kunna erbjuda polymeravledare för högre spänningar har en ny produkt tagits fram. Den nya produkten kallas <em>PEXLIM Stark. </em></p><p>Med den nya produkten innebär en mängd processer som måste arbetas fram. En sådan process är slutmontaget där man monterar de sista detaljerna.</p><p>Detta arbete har gjorts för att se vilka problem som kan uppstå vid slutmontaget och hur man löser dessa på bästa sätt.</p><p> </p><p> </p> / <p> </p><p>ABB has a big factory in Ludvika where many kinds of apparatus for high voltage systems are manufactured. Among the products are surge arresters, which are used to protect other equipments in power systems against all type of transient overvoltages. The arresters manufactured in Ludvika are for voltage systems from around 52kV up to 800kV which is the highest system voltage level in the world so far. The active elements in the arresters are blocks of ZnO material. The arresters are manufactured utilizing two types of enclosures, porcelains and polymer. Due to the good response from the customers more and more arresters are manufactured with polymer housings but so far the mechanical strength has prevented polymer designs for higher voltages than approximately 245kV. In a new project, therefore, a polymer housed arrester with higher mechanical strength will be developed. The working name for the new product is <em>PEXLIM Strong. </em>Among all the problems which have to be solved during the development of the new product is also how the final assembly of the product shall be performed. In this report, as part of a Bachelor of Science in Machine Engineering, the problems are analyzed and different solutions to obtain an efficient final assembly of the new product are suggested.</p><p> </p><p> </p>
13

Konceptförslag för detaljhantering i en svetsrobotcell / Concept for handling items to be processed by a welding robot

Hinders, Fredrik January 2009 (has links)
<h2>Abstract</h2><p>At the plant of Outokumpu Stainless Tubular Products AB in Molkom a wide range of butt weld fittings are produced. These are aimed mainly for the process industries and one of the products are ninety degree bend elbows in various dimensions. The elbows are made from stainless sheet metal and when formed to a tube they need to be welded along its inner radius. This is made by a pick and place type industrial robot working in a closed compartment. The assignment given by Outokumpu aims to investigate and suggest a new concept for a more reliable manufacturing process within the work cell.</p><p> </p><p>The cell consists of five main areas chronologically listed as passed by the elbow:</p><p>·          Automated, vibrating conveyor.·          Fixture with the purpose to serve the robot with one elbow at a time, placed in the correct position.·          Industrial robot to pick up the elbow and drag it along the welding head.·          TIG inverter with a stationary welding head·          A hydraulic press with a template of the final shape of the elbow corrects flaws. Almost every problem in the cell and defects on the products coming out of it can be traced back to the fixture and in some cases also to the robots pick up tooling. The focus of the task was therefore put mainly on those two areas. As the work proceeded Outokumpu chose to develop a new tool for the robot themselves which they did with good results. I chose to incorporate it into my study and change focus to the fixture instead.</p><p> </p><p>The problems and possible causes to them were identified and discussed with my tutor:</p><ul><li>The elbows fall incorrectly into or beside of the fixture.  <ul><li>Fixtures are old and worn down.</li><li>The elbows path between conveyor and fixture are somewhat out of control</li><li>The smaller dimensions have room enough to slip past the fixture. <ul><li>Edges to be welded are to far from each other or badly shaped</li></ul></li></ul></li><li>Commissioning time, some start up steps is more complex then they need to be. <ul><li>Some of the setting possibilities in the working cell are unnecessary and can be fixed instead.</li><li>The positions of pick up and welding head are not really fixed in the robot software, these are reprogrammed every time elbow size are changed.</li></ul></li></ul><p>·          Various errors at weldingo    Robot managed to pick incorrectly placed elbow</p><p> </p><p>Proposals to solve the above specified problems:</p><ul><li>All parts in contact with the elbows are to be made of harden able steel. A suitable one is C45E which can be casehardened to about 700HV.</li><li>On the outer edge of the conveyer a support are placed to prevent excessive wear.</li><li>The fixture is partially redesigned with a support to control the elbows path better.</li><li>Guide arms with dual purpose are added. First they guide the elbow into the fixture and secondly they turn it to the correct angle towards the robot.</li><li>Pins are used along with quick lock clamps to obtain faster and easier commissioning.</li><li>The pick and place tool developed by Outokumpu are used.</li></ul>
14

Konceptförslag för detaljhantering i en svetsrobotcell / Concept for handling items to be processed by a welding robot

Hinders, Fredrik January 2009 (has links)
Abstract At the plant of Outokumpu Stainless Tubular Products AB in Molkom a wide range of butt weld fittings are produced. These are aimed mainly for the process industries and one of the products are ninety degree bend elbows in various dimensions. The elbows are made from stainless sheet metal and when formed to a tube they need to be welded along its inner radius. This is made by a pick and place type industrial robot working in a closed compartment. The assignment given by Outokumpu aims to investigate and suggest a new concept for a more reliable manufacturing process within the work cell.   The cell consists of five main areas chronologically listed as passed by the elbow: ·          Automated, vibrating conveyor.·          Fixture with the purpose to serve the robot with one elbow at a time, placed in the correct position.·          Industrial robot to pick up the elbow and drag it along the welding head.·          TIG inverter with a stationary welding head·          A hydraulic press with a template of the final shape of the elbow corrects flaws. Almost every problem in the cell and defects on the products coming out of it can be traced back to the fixture and in some cases also to the robots pick up tooling. The focus of the task was therefore put mainly on those two areas. As the work proceeded Outokumpu chose to develop a new tool for the robot themselves which they did with good results. I chose to incorporate it into my study and change focus to the fixture instead.   The problems and possible causes to them were identified and discussed with my tutor: The elbows fall incorrectly into or beside of the fixture.  Fixtures are old and worn down. The elbows path between conveyor and fixture are somewhat out of control The smaller dimensions have room enough to slip past the fixture. Edges to be welded are to far from each other or badly shaped Commissioning time, some start up steps is more complex then they need to be. Some of the setting possibilities in the working cell are unnecessary and can be fixed instead. The positions of pick up and welding head are not really fixed in the robot software, these are reprogrammed every time elbow size are changed. ·          Various errors at weldingo    Robot managed to pick incorrectly placed elbow   Proposals to solve the above specified problems: All parts in contact with the elbows are to be made of harden able steel. A suitable one is C45E which can be casehardened to about 700HV. On the outer edge of the conveyer a support are placed to prevent excessive wear. The fixture is partially redesigned with a support to control the elbows path better. Guide arms with dual purpose are added. First they guide the elbow into the fixture and secondly they turn it to the correct angle towards the robot. Pins are used along with quick lock clamps to obtain faster and easier commissioning. The pick and place tool developed by Outokumpu are used.
15

Flermålsoptimering och analys av produktionslinje samt identifiering av förbättringsmål

Bremert, Michael, Persson, Stefan January 2012 (has links)
Volvo Powertrain vill på grund av ökad efterfrågan öka produktionstakten av 13 liters cylinderhuvuden. Bearbetningen är uppdelad i produktionslinjer som består av grupper med CNC-maskiner som betjänas av en portalrobot i ett enstycksflöde. Målet för produktionstakten i grovdel 2 har satts till 33 cylinderhuvuden per timma. Volvo Powertrain har också genom sitt produktionsuppföljningssystem, Duga identifierat maskinernas tidsförlust för väntan på portalroboten som en signifikant del av den planerade produktionstiden. Syftet med detta arbete är dels att genom simulering analysera och fastställa om maskinernas tidsförluster för väntan på portalroboten stämmer med verkligheten, dels att genom simuleringsbaserad optimering hitta realistiska förbättringsförslag för att uppnå uppsatt mål för produktionstakten. Arbetet behandlar inte de ekonomiska konsekvenserna med föreslagna åtgärder, kvalitetsbrister eller bemanning vid produktionslinjen. För att svara på frågan om maskinernas tidsförluster på grund av väntan på portalrobot gjordes först en simuleringsmodell över en produktionscell. I produktionscellen finns fyra maskiner som betjänas av en portalrobot. Simuleringsmodellen programmerades till att räkna och dela upp olika typer av väntetid för maskinerna. Resultaten från simuleringsmodellen visar att maskinernas väntan inte är så hög i verkligheten som den redovisas i Duga. Differensen beror på hur maskinernas väntan på laddningsutrustning definierats i Duga. För att svara på frågan om vad som kan göras för att öka produktionstakten byggdes först en generisk modul över en portalrobot upp, och med hjälp av denna byggdes en simuleringsmodell över grovdel 2. Med denna simuleringsmodell har tre optimeringar med olika parametrar körts med en optimeringsklient tillhandahållen av Högskolan i Skövde. Det scenario som innebär att buffertnivåer ändras, omtaktning av cykeltid mellan maskiner sker samt en förbättring av maskinernas tillgänglighet ger att produktionstakten uppnår uppställda mål. Ett realistiskt lösningsförslag har tagits fram som innebär en ökning av dagens produktionstakt med 10 %. / To meet the demands from their customers Volvo Powertrain has set a new production goal for cylinder heads for 13-liter diesels engines. The production lines are built as a flow line of grouped CNC machines, served by a gantry for loading and unloading. The new production goal for one of the production lines, segment 2, is 33 cylinder heads per hour. Volvo Powertrain has also found through the production monitoring-system, Duga, that the waiting time for the loading equipment is a significant amount of the available production time. The aim of this project is hence twofold: (1) to verify that the calculations of the waiting time made in Duga are correct; (2) to investigate and propose improvements for the production line in order to achieve the original targeted production goal. This has been done by using simulation and simulation-based optimization technology and for this purpose a generic simulation module of a gantry was made. This project will not answer questions regarding economic consequences, staffing and quality losses in the production line. A simulation model has been built in the first phase of the project for a machining cell in Segment 2, which contains one gantry for the loading and unloading operations of four different CNC machining centers connected in series. The simulation model shows that the waiting time of the loading equipment in real time is not as big as what is calculated in Duga. This discrepancy is due to a misleading definition of the waiting time made in Duga. The generic gantry module has been used to build a simulation model of Segment 2. Three different optimization runs has been made with an optimization client from the University of Skövde. One of the optimization runs found a solution that matches Volvo Powertrains production goal. From this optimization run one preferred and realistic solution was chosen. The solution includes new levels in buffers along the production line, line balancing and improved availability to the different machines and gantries. The preferred and realistic solution increases the production rate by 10%.
16

Den nya generationen KinBag : The new generation of KinBag

Svensson, Patrik, Klippberg, Lovisa, Jansson, Björn January 2007 (has links)
This report summarizes a Bachelor Degree Project in Integrated Product Development,carried out during the spring semester in 2007 by three students at the Product Design Engineering programme at the University of Skövde. The project was performed as an assignment for KinBag ab, a sister subsidiary to Kinnegrip ab in Lidköping, who develop,manufacture and market the golf bag KinBag, a bag with an integrated wheel carriage system. The purpose of the project was to redesign the golf bag to attract a target group consisting of golfers aged between 20 and 40. The layout of the project was as follows: The project began with a feasibility study where different problems were identified with the basis of a market research which eventually was summarized in a dynamic specification of requirements. The feasibility study was followed by a generation of ideas which contained everything from sketches to simple mock-ups with an intensive amount of thoughtful brainwork and information gathering in between. This led to the development of a number of design concepts, both on an overall level and on different parts of the golf bag. Even more detailed models were created and visualized in a three dimensional environment by means of a CAD program. The report portrays the product design process and methods utilized in the project, as well as the final result - a full-scale operational prototype of the new generation of KinBag.
17

Automation of packing process

Zia, Muhammad Irfan, Cortés Mora, Felipe January 2008 (has links)
The design work that precedes the automation of a process is not an easy job. Each one of the variables and possible risks involved in process must be carefully considered before implement the final design as well the requirements in performance and cost. However automate a dangerous, inefficient or just uncomfortable task entails many benefits that make up for the long period of design process. A well automated line will benefit the production with quality, productivity and capacity among other profits. In this project the immediate objective is to automate the “SANDFLEX Hacksaw blades” packaging process in the plant that SNAEurope owns in Lidköping. Actually the packing is completely manual. One operator packs the blades into the boxes meanwhile one more operator loads and unloads the packing station with empty and full boxes respectively. The task is both, tiring and uncomfortable for the operators as well inefficient for the company since the production rate is limited. Analyzing and observing carefully product and process, different theories and strategies to achieve the goal were developed. Three are the possible solutions to solve the problem, with different levels of automation and technologies. The robotic solution uses an articulated robot to perform all the tasks; the hybrid solution uses pneumatic devices to pack the blades and an articulated robot to support the station loading and unloading the boxes. Finally the pneumatic solution uses only pneumatic devices, which hold, open and close, push box and blades using airpower; a few sensors detect positions and states, since a PLC coordinates and controls all process. By means of discussing these solutions with the company’s engineers and workers, after a deep literature study and two test of performance, was it possible to select the most suitable solution to accomplish the packaging task. The pneumatic solution is cheap and simple, but at the same time robust and reliable. This design performs the packaging task efficiently and fast. And more important, the operator passes from pack manually the blades to monitor the process.
18

Optimering av fixtur och operationer : för effektivare produktion

Larsson, Johan January 2010 (has links)
No description available.
19

Analysis of a Production Cell using Production Simulation Tools

Hägg, David, Hofmeijer, Victor January 2010 (has links)
This final thesis was performed at Ecole Nationale Supériure D’Arts et Métiers (ENSAM) in Lille, France. The aim of the thesis has been to use two different simulation tools to analyse an existing production cell with focus on industrial engineering. The possible use and the usability of the simulation tools are also studied. The models built for simulation have been used to gather data about the cell. After analyse and discussion about the data we came to the following conclusions. The bottleneck in the cell is the Stäubli. A cheap and simple way to improve the cell is by adding new decision points (sensors) to it. The most efficient location of the new decision points is before and after the Stäubli. The production rate reaches its maximum rate for both settings with eight pallets. If the improvements are implemented then there is no reason to change the speed of the conveyor. With basic settings the speed can be increased for better productivity. The most efficient production type for short setup times is single, for both settings. Delmia is useful for visual representation. It’s also useful for measurements of time and distance since the accuracy is very high. Delmia is useful as common platform when to discuss and explain thoughts and ideas about a project. Flow simulation in Quest provides a great understanding of the production and the behaviour of the cell. It is very easy to get data in and out of the program and to compare results and impacts of changes.
20

Deburring of components : A survey of current and future deburring processes

Alallak, Ali January 2010 (has links)
The machining operations that shape a metal component produce a raised edge or small pieces of material remaining attached to a work piece called burrs and sharp edges. The deburring process is intended to remove these imperfections and produce specific edge profiles. Burr formation during machining operations is one of the most significant problems encountered by industrial companies in component manufacturing. Remaining burrs after machining pose a severe risk for component breakdowns, if the burrs get loose. All work piece edges must therefore be completely defect-free. In the machining industry manual methods are commonly employed for burr removal. Fully automating deburring operations present a major challenge. Furthermore, removal of internal burrs of various sizes and shapes from parts sometimes becomes an extremely difficult task which causes high cost for labor, time losses, and health and safety risks. Increasingly, manufacturers are expected to deliver burr-free parts to their customer. Sandvik Coromant, Scania and Volvo Cars are three of these manufacturers, and these three companies have agreed to contribute to this thesis. Sandvik Coromant AB is part of the global enterprise Sandvik Group AB, and is world- leading in providing and developing cutting tools for the metal working industry. The company operates in over 60 countries worldwide and its main production plant is located in Gimo, Sweden [www.sandvik.com]. Scania is a global automotive industry manufacturer of commercial vehicles—specifically heavy trucks and buses. It also manufactures diesel engines for motive power of heavy vehicles, marine, and general industrial applications. Scania was founded in 1891 in Södertälje, Sweden. Today, Scania has ten production facilities worldwide [www.scania.com]. Volvo Car Corporation is an automobile manufacturer founded in 1927, in Gothenburg, Sweden. Volvo Cars has approximately 2,300 local dealers and around 100 national sales companies worldwide. Volvo Car Engine is a part of Volvo Cars. Volvo Car Engine produces engines and other components for other units, and it is headquartered in Skövde, Sweden [www.volvocars.com]. All of the companies above have problems in burr minimizing and removing strategy in machining and deburring operations to achieve quality assurance. Therefore, to choose a deburring system, and to reveal the results of deburring operations, it is necessary to be able to inspect/measure burrs. But, unfortunately, most industrial companies today lack the specialized systems to measure the presence of burrs, which adversely affect the overall deburring process. In this thesis, different types and sizes of work pieces have been taken directly from the production to measure burrs, and conduct experiments on them. The thesis focuses on three areas: A survey of the current deburring problems, including burr classification and measurement, current minimization strategies of burr formation, and current deburring methods. Experiments on new and improved deburring methods, including deburring tools (e.g. drilling deburring tools, countersink tools, grinding tools and alumina fiber brushes), water-jet deburring (multi-nozzle rotary lance jets, pure and abrasive single rotary nozzle water jets). A selection matrix as a thesis conclusion which relates these methods to criteria of deburring processes, such as process performance, industrial applications, quality assurance, safety and environment, costs, etc. This matrix can be a basis for a more detailed selection/decision matrix in the future. / QC 20101203

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