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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.
341

Obrábění odlitku převodovky na CNC stroji / Machining of the gear-box casting on a CNC machine

Hložek, Milan January 2018 (has links)
The master’s thesis focuses on the machining of a chosen gearbox on a CNC machine. The theoretical part deals with gearboxes in general and the aluminium alloy from which a selected gearbox is manufactured. In the practical part, the machining of the gearbox is proposed according to the corresponding drawing. Gradually suitable machines are selected, then depending on their limits, clamping devices are designed, next a set of tools is selected and an NC program is generated. The technological process of production is proposed and the basic production costs are calculated.
342

Optimalizace obráběcího procesu s průmyslovou aplikací na obráběcím centru / Optimisation of machining process for an industrial application and a CNC machining centre

Soukupová, Veronika January 2020 (has links)
Tato diplomová práce byla vypracována v průmyslovém kontextu, během stáže ve firmě Metso. Zlepšení obráběcího procesu zajišťovacích šroubů bylo cílem této práce, aby byla umožněna budoucí automatizace zakládání obrobku do stroje. Zlepšení bylo zhodnoceno na základě úrovně autonomie během obrábění, eliminace neprogramovaných zastavení stroje operátorem a dostačujícího odvodu třísek. Implementace automatických systému do číslicově řízeného obráběcího centra umožňuje zvýšení produktivity. Před automatizováním obráběcího procesu však musí být proces optimalizován. Zejména dostatečná fragmentace třísek a jejich evakuace jsou klíčové. Dlouhé nedělené třísky můžou poškodit systémy jako například automatický měnič nástrojů, dopravník třísek nebo průmyslového robota. Dostatečná lámavost třísek může být zaručena správným výběrem technologie a strategie obrábění, výběrem řezného nástroje a řezných podmínek pro daný materiál obrobku.
343

Drátové elektroerozivní obrábění při výrobě nástrojů pro dřevoobrábění / Wire electrical discharge machining at production of tools for working of wood

Sedláček, Jiří January 2008 (has links)
My thesis is aimed at the application of wire electical discharge machining technology in the production of woodworking tools. All of this in the conditions of Vydona company. There is a theory of machining method plus a well-aranged division of cutter tools for wood in the introduction. The practical part describes in detail the procedur of cutting shaped plate out of tungsten carbide. As a result of the technical and at the same time the economic evaluation is an establishment of hourly rate for machine.
344

Trendy vývoje obráběcích strojů / Trend development of machine tools

Šenkýř, Pavel January 2008 (has links)
This diploma thesis deals with trends of the development of machine tools, and focuses on technologies and machine tools for manufacturing of pressing dies and on manufacturing of cavity of moulds. First, the existing state in the field of these technologies is described and defined, and subsequently, the dissertation concentrates on modern conceptions of this manufacturing.
345

Optimalizace technologie součásti "nosná deska" ve firmě PROMAT Vsetín / Optimalization technology of production "nosná deska"-part in condition firm PROMAT Vsetín

Juráň, Jaromír January 2008 (has links)
Valorization and analysis of machining technology for the production of aluminium part and consecutively project optimization part production. New advanced cutting tools selection and application of new technologies. The adjustment and simplification of the existing NC program for given CNC machining centre and its final debugging. In the final part, there is an economical and technical evaluation of firm benefits and recommendations into production.
346

Technologie výroby součástky konzola / Technology of Production Parts Console

Rusník, Tomáš January 2011 (has links)
This thesis describes the complete technology solution of front driving axle console production by machining. The console is part of the self-supporting structure of the tractor and is produced under conditions of large engineering company. Introduction describes the prduction technology of component. The main part is devoted to the technological process of production and selection of appropriate cutting tools. Technical and economical evaluation of machined part is mentioned in the conclusion of thesis.
347

Technologie elektrojiskrového drátového řezání / Technology of wire electrical discharge machining

Brázda, Radim January 2013 (has links)
This master´s thesis deals with unconventional technology of wire electrical discharge machining. There are described the principles and essence of electrical discharge machining and the principles related to wire electrical discharge machining with emphasis on the application of this technology in terms of medium-sized engineering company. There is also described the complete assembly of technolgy wire cutting and machining on wire cutter Excetek V 650. Then in the work there are statistically evaluated parameters precision machined surfaces, specifically to the belt pulley 116-8M-130. At the end of the work there is the technical-economic evaluation that addresses the hourly cost of machining on wire cutter Excetek V 650.
348

Konstrukce multifunkčního obráběcího centra / Design of multi-functional machining centre

Matěja, Josef January 2013 (has links)
The Diploma thesis deals with the design solution of multi-functional machining centre, especially with one of its parts – the design of the slide ram and vertical feed incl. the choice of convenient tool heads for the slide ram. The introducing part deals with the numerically controlled machines and centres generally, especially with the portal-type ones. It contains description of individual machine parts including examples of accessories from product plans of domestic and foreign producers. The second part of the Diploma thesis contains calculations and design solution of the slide ram and feed including the choice of the most suitable accessories applicable for this purpose. In the final phase the model of the slide ram has been introduced in the imersion virtual reality and integrated in the complete machine design. The Diploma thesis has been elaborated using the relevant technical literature.
349

Vysokorychlostní obrábění ložisek z materiálu 100Cr6 / High-speed Machining of Bearings from Material 100Cr6

Tropp, Pavel January 2015 (has links)
This Master's thesis deals with the issue of high-speed turning of the 100Cr6 material. The aim is to identify and experimentally validate an innovative production process for a particular component. The thesis includes theoretical basis of high-speed machining, analysis of the current state of the manufacturing process, innovation design and experimental verification. At the end of the thesis, parameters of the machined surfaces of specimens are evaluated.
350

Integral Approach for Hybrid Manufacturing of Large Structural Titanium Space Components

Seidel, André 19 April 2022 (has links)
This thesis presents a newly developed manufacturing method, based on cyber-physically enhanced hybrid machining, regarding an optical bench (OB) made of Ti6Al4V alloy for the Advanced Telescope for High-ENergy Astrophysics (ATHENA). The method includes sophisticated hybrid laser metal deposition equipment and state-of-the-art cryogenic machining hardware. The derived strategy combines localized energy input, preheating, heat treatment, intermediate stress relief and machining. This results in a complex thermal history and remaining residual stresses, representing a considerable challenge for final precision machining. The method targets first time right machining based on iterative machining, process data-based tool path correction and spatially resolved root cause research based on process data modeling.:II. Table of Contents I. Acknowledgement ............................................................ III II. Table of Contents ................................................................. I 1. Introduction ........................................................................ 1 1.1 Foreword .................................................................................... 1 1.2 Research Subject Lot Size One ....................................................... 2 1.2.1 Historical Perspective ................................................................. 2 1.2.2 Going Full Cycle ......................................................................... 3 2. State of the Art in Titanium Processing ............................... 4 2.1 Conventional Processing................................................................ 4 2.2 Additive Manufacturing ................................................................. 5 2.2.1 Introduction .............................................................................. 5 2.2.2 Powder Bed Fusion ..................................................................... 6 2.2.3 Direct Energy Deposition ............................................................. 8 3. Derivation of a Flexible Hybrid Manufacturing System ...... 11 3.1 The ATHENA OB – a Large Structural Space Component ..................11 3.2 Material Constraints ....................................................................12 3.3 Solidification and Microstructural Content .......................................17 3.4 Residual Stresses and Intrinsic Heat Treatment ..............................22 3.4.1 Transient Temperature Gradients ................................................22 3.4.2 Residual Stresses and Degree of Fixity ........................................24 3.4.3 In-situ Stress Relief and Plastic Deformation ................................28 3.4.4 In-situ Martensite Decomposition and Thermal Trade-off ...............30 3.5 Melt Pool Considerations in Laser Metal Deposition ..........................36 3.6 Concept of Flexible Hybrid Manufacturing Cell .................................43 3.7 Process and Equipment Review by ESA ..........................................45 4. Realization of a Flexible Manufacturing Cell ...................... 45 4.1 Additive Processing with Hybrid Laser Metal Deposition ....................45 4.1.1 Principle Hardware ....................................................................45 4.2 Novel Local Shielding Solution ......................................................47 4.2.1 Melt Pool Observation towards Process Data Model ........................51 4.2.2 Energy Source Coupling .............................................................57 4.3 Subtractive Processing with Cryogenic Milling .................................57 4.3.1 General Considerations for Subtractive Processing ........................57 4.3.2 Cryogenic Machining Approach ...................................................58 4.3.3 Cryogenic Machining from the Materials Viewpoint ........................60 4.3.4 Cryogenic Machining of Additively Manufactured Ti-6Al-4V .............62 4.3.5 Principle Hardware for Cryogenic Milling with CO2..........................66 4.3.6 Intelligent Tool Spindle Future Part of the Process Data Model ........69 4.3.7 Carbon Dioxide Weighing Equipment and Switching Station ............70 4.3.8 Protective Measures for Safe Use of Cryogenic CO2 .......................72 4.4 Handling System .........................................................................74 4.4.1 Framework Considerations .........................................................74 4.4.2 Twin Robot System in the Initial State .........................................76 4.4.3 Integration of the ATHENA Turntable ...........................................79 4.4.4 Robot Calibration ......................................................................81 4.5 Lighting for Visual Inspection ........................................................84 4.6 Critical Design Review by ESA .......................................................84 5. Implementation and Validation ......................................... 85 5.1 Powdery Filler Material Selection ...................................................85 5.2 Basic Parameter Set for Additive Manufacturing ..............................87 5.2.1 Operating Point Selection ...........................................................87 5.2.2 Characterization and evaluation ..................................................89 5.2.3 Substrate to Structure Transition ................................................95 5.3 Energy Source Coupling ...............................................................99 5.3.1 Process Development ................................................................99 5.3.2 As-built Surface Treatment ...................................................... 103 5.3.3 Heat Treatment ...................................................................... 104 5.3.4 Mechanical Testing .................................................................. 106 5.3.5 Fractured Surfaces .................................................................. 108 5.3.6 Microstructure ........................................................................ 110 5.3.7 Linear Expansion Coefficient ..................................................... 113 5.4 Cryogenic Milling ....................................................................... 114 5.4.1 Strategy Approach .................................................................. 114 5.4.2 Milling Implementation ............................................................ 116 5.4.3 Technical Cleanliness ............................................................... 120 5.4.4 Accuracy and Duration ............................................................. 122 5.4.5 Surface Roughness.................................................................. 122 5.5 Process Data Model ................................................................... 123 6. Final Discussion and Conclusions..................................... 130 6.1 Summary ................................................................................. 130 6.2 Conclusions .............................................................................. 131 6.3 Outlook .................................................................................... 132 III. List of Figures ...................................................................... I IV. List of Tables .................................................................. VIII V. References ......................................................................... IX VI. Symbols and Units ....................................................... XXXVI VII. Abbreviations .............................................................. XXXIX VIII. Annex I ............................................................................ XLI IX. Annex II ....................................................................... XLIII X. Annex III ....................................................................... XLIV XI. Annex IV.......................................................................... XLV XII. Annex V ......................................................................... XLVI XIII. Annex VI....................................................................... XLVII XIV. Annex VII ................................................................... XLVIII

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