Dissertations / Theses on the topic 'Manufacturing processes'
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Ramudhin, Amar. "Two-stage manufacturing processes." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/24561.
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Lu, Ilyssa Jing. "Innovation enabling manufacturing processes." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44309.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Manufacturing Program at MIT, 2008.Includes bibliographical references (p. 61-62).
Global operations for multinational companies today pose a particularly challenging environment for maintaining fluid knowledge transfer and effective communication methodologies. In a continuous drive for product innovation, process development often takes on lower priority to other initiatives that directly affect the design and delivery of a product. However, existing literature shows that process development and governance are critical to sustainable growth in the global marketplace. Multinational companies must recognize the need to integrate process development in a product centric enterprise to maintain effective information flow and clear communication channels. Cisco faces this challenging in maintaining effective cross-functional communication while growing through acquisition and new product developments. Cisco also faces additional complexity in managing a global network of outsourced manufacturing activities. This research analyzes two case studies in process development within the Manufacturing organization at Cisco. Specifically, these two case studies focus on driving early engagement of manufacturing concerns in the product lifecycle and effective means of facilitating this initiative.
by Ilyssa Jing Lu.
S.M.
M.B.A.
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Nielssen, Johan. "Information modeling of manufacturing processes." Doctoral thesis, KTH, Production Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3628.
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The innovation process is an important process for our primemotor of welfare, manufacturing. During this process, theprerequisites for manufacturing are set. To set the bestpossible prerequisites consideration about products,manufacturing processes, and manufacturing resources must bemade concurrently, which also means involving several differentdisciplines in a collaborative effort.
As a consequence of involving different disciplines, thecommunication of engineering information may be hindered. Thereason is that different disciplines use different terminologyfor the same concept and sometimes have the same terminologyfor different concepts. This may result in difficultiesunderstanding each other, which may, in turn, result inunnecessary loss of quality and productivity.
The main objective of this thesis is to identify informationconcepts (i.e. information requirements) for process planningin a concurrent engineering environment, and to formally definethe corresponding terminology. The work is based on casestudies at Volvo Car Corporation, involving management of weldspot and location system information, and at ABB Body-in-White,involving tender preparation information.
The results are presented in the thesis in terms of aninformation model, the Product-Process-Resource (PPR)information model, and two corroborated hypotheses. The PPRinformation model defines the identified informationrequirements in the scope of the thesis whereas the hypothesesconcern how, e.g., modularization can be used in informationmodeling.
The PPR information model provides the base for aninformation platform in a concurrent engineeringenvironment.
The PPR information model enable model based documentationand, thus, traceability of the evolution of the product,process, and manufacturing resource designs, and theirinterrelations.
Keywords:Information Modeling, Process Planning,Concurrent Engineering, Information Management
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Wang, Kaimei. "Chinese firms' manufacturing internationalization processes." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608893.
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Hides, Michael. "New products into manufacturing." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341312.
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Turner, David Bentley. "An assessment of Magic Metal Company." Online version, 1998. http://www.uwstout.edu/lib/thesis/1998/1998turnerd.pdf.
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Sánchez, Egea Antonio José. "Electropulsing to assist conventional manufacturing processes." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/385428.
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This thesis presents a study on the variation of the mechanical properties of some materials. These variations are registered for processes as bottom bending, wire drawing or round turning, which are performed under high density electropulses. This research implied the study of several issues related to the manufacturing processes and the electric pulses. For example, some isolated systems are developed for each process. This is required for protecting the monitoring devices and machinery from electric drifts.
On the other hand, several electropulse generators are designed and manufactured to electrically assist the aforementioned manufacturing processes. The electrical connectors is the main technological issue in each process to ensure good electrical contact during experimentation.
Once the manufacturing setup is under control, electropulses are applied on various materials whilst its physical properties are measured and recorded. In particular, the processes are achieved under different electric configurations to infer the influence of the electropulses. The obtained results show that different mechanical and manufacturing properties like elastic restoring forces, yield strength, power consumption, surface roughness and material hardness among others are modified when the manufacturing process is assisted with a pulsed electric field. Additionally, the machinability and formability is improved when the metallic material is affected by current pulses. However, it should be noted that the mechanical properties behavior under different electrical parameters, like current density, frequency discharge and pulse duration, is complex and does not follow an expected relationship. Furthermore, numerical simulation analyses is required to study and understand the complex
behavior of the mechanical properties.
The manufacturing process of bending, machining and drawing process was done at the Universitat Politècnica de Catalunya (Spain) in collaboration with the Northwestern University (USA), the Universidad Pontificia Universidad Católica de Chile (Chile) and the Universidad Tecnológica de Pereira (Colombia). This thesis is funded by the Ministry of Economy and Competitiveness of Spain, reference project: DPI2011-26326 (grant no. BES-2012-056760).
Along the document detailed information on methodology for the aforementioned processes and some conclusions are providedEn el presente estudio se documenta la variación de las propiedades mecánicas registradas en diversos procesos de fabricación, doblado, mecanizado y trefilado, cuando estos procesos son asistidos con generadores de pulsos de alta densidad de corriente Para cada proceso de fabricación se ha realizado un utillaje específico para aislar eléctricamente la máquina de ensayo. Esto permite inducir los pulsos de corriente únicamente a través de las probetas metálicas, sin correr el riesgo de inhabilitar las máquinas de fabricación. Varios generadores de pulsos de corriente han sido diseñados y fabricados a lo largo de la tesis para asistir eléctricamente los procesos de fabricación mencionados. Para cada estudio se varía el área de contacto de los conectores eléctricos con el material para asegurar un buen contacto eléctrico durante la experimentación. La influencia de los pulsos de corriente eléctrica en los diferentes materiales manufacturados ha sido registrada y estudiada por varios equipos de medida. Además, se ha necesitado de programas de simulación numérica para estudiar y comprender el comportamiento de las propiedades mecánicas. Los resultados obtenidos en este trabajo demuestran que varias propiedades mecánicas como la recuperación elástica, esfuerzos de fluencia, potencia consumida, rugosidad superficial y dureza del material entre otras son modificadas cuando los procesos de fabricación son asistidos por un campo eléctrico. En resumen, se observa que la maquinabilidad del material metálico mejora cuando es fabricado bajo la influencia de los pulsos eléctricos. Esto es debido a que se reduce los esfuerzos de fluencia, mejora la rugosidad superficial, se atenúa la recuperación elástica y disminuye su dureza superficial. Aun así, cabe indicar que el comportamiento de las propiedades mecánicas anteriores bajo las condiciones eléctricas son complejas y no siguen una relación trivial. Indicar que los avances en el área de fabricación realizados en este trabajo en los procesos de doblado, mecanizado y trefilado han sido realizados en la Universitat Politècnica de Catalunya (UPC), Escola Universitaria d'Enginyeria Tècnica Industrial de Barcelona (EUETIB) en colaboración con la Pontificia Universidad Católica de Chile (PUC), la Universidad Tecnológica de Pereira (UTP) y la Northwes tern University. En consecuencia, a lo largo del documento se detalla la metodología de estudio y los resultados obtenidos de los diferentes procesos mencionados, comparando los procesos convencionales respecto a los asistidos. Además, se estudiará en profundidad la influencia de los pulsos de corriente en el comportamiento de las principales propiedades mecánicas, según el proceso.
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Markusson, Lisa. "Powder Characterization for Additive Manufacturing Processes." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-62683.
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The aim of this master thesis project was to statistically correlate various powder characteristics to the quality of additively manufactured parts. An additional goal of this project was to find a potential second source supplier of powder for GKN Aerospace Sweden in Trollhättan. Five Inconel® alloy 718 powders from four individual powder suppliers have been analyzed in this project regarding powder characteristics such as: morphology, porosity, size distribution, flowability and bulk properties. One powder out of the five, Powder C, is currently used in production at GKN and functions as a reference. The five powders were additively manufactured by the process of laser metal deposition according to a pre-programmed model utilized at GKN Aerospace Sweden in Trollhättan. Five plates were produced per powder and each cut to obtain three area sections to analyze, giving a total of fifteen area sections per powder. The quality of deposited parts was assessed by means of their porosity content, powder efficiency, geometry and microstructure. The final step was to statistically evaluate the results through the analysis methods of Analysis of Variance (ANOVA) and simple linear regression with the software Minitab. The method of ANOVA found a statistical significant difference between the five powders regarding their experimental results. This made it possible to compare the five powders against each other. Statistical correlations by simple linear regression analysis were found between various powder characteristics and quality of deposited part. This led to the conclusion that GKN should consider additions to current powder material specification by powder characteristics such as: particle morphology, powder porosity and flowability measurements by a rheometer. One powder was found to have the potential of becoming a second source supplier to GKN, namely Powder A. Powder A had overall good powder properties such as smooth and spherical particles, high particle density at 99,94% and good flowability. The deposited parts with Powder A also showed the lowest amount of pores compared to Powder C, a total of 78 in all five plates, and sufficient powder efficiency at 81,6%.
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Roth, Benlloyd Koekemoer. "Enablers for lean process sustainability within South African manufacturing industries." Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/6591.
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James Womack and his colleagues Daniel Jones and Daniel Roos changed the way western civilization approached manufacturing. In 1990, they published a book called ‘The Machine That Changed the World: The Story of Lean Production’. It was a concept that had slowly filtered from the east but had not made its mark on the manufacturing sector. The concept of lean, born out of the Japanese Toyota Manufacturing System, was first thought to be impossible to duplicate outside of Japan. Since Womack and company popularised this “new” way of producing goods and delivering services it spread across industries finding popularity in the medical, engineering, accounting and especially the manufacturing industries. Over the last few decades lean practices has been synonymous with efficiency, cost reduction, supply chain optimisation and innovative problem solving (Anvari Norzima, Rosnah, Hojjati and Ismail, 2010; Pieterse et al., 2010; Womack et al., 1990). Lean process implementation has been researched in abundance, as has failed attempts at lean implementation. The purpose of this study was to identify and assess enablers of lean sustainability in organisations where lean processes are already being implemented. The literature study found Organisational Culture, Leadership, Employee Engagement and Trade Unions participation as factors that contributed to successful lean implementations. The author developed a model to test Organisational Culture, Leadership, Employee Engagement and Trade Unions as enablers to sustain lean practices in organisations in South Africa’s manufacturing industries. The results proved that Organisational Culture, Leadership and Employee Engagement were considered enablers for lean sustainability. These three enablers have an interlinked relationship and together help sustainability. Lacking just one factor would surely result in unsustainable lean practices. The study was conducted in the quantitative paradigm, as the hypothesised relationship was statistically tested. The data was collected from a homogenous group via an email sent with a link to the questionnaire. The data was statistically analysed with Statistica software and Microsoft Excel.
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Afazov, Shukri. "Simulation of manufacturing processes and manufacturing chains using finite element techniques." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10827/.
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This thesis presents work on the simulation of manufacturing chains, simulation of manufacturing processes (casting, forging, shot-peening and heat treatment) and fatigue life prediction by using the finite element method (FEM). The objectives and the contributions of this thesis consist of development of mathematical algorithms and techniques for mapping and transferring FE data (stresses, strains, displacements, etc.) from macro-to-macro and micro-to-macro FE models among different FE solvers and meshes. All these features have been implemented into a new finite element data exchange system (FEDES). FEDES has been developed to simulate manufacturing chains by using FE techniques. Extensive research has been carried out on the simulation of investment casting processes of aero-engine parts under equiaxed and directional cooling. Methodologies for predicting the component life undergoing low cycle fatigue (LCF) and high cycle fatigue (HCF) have been developed. Life prediction based on the effect of the residual stresses obtained from micro machining and shot-peening processes has been investigated. FEDES has been used to simulate two manufacturing chains where the residual stresses and the distortions after each manufacturing process have been passed to the next process of the chain. Manufacturing chain simulation including casting, forging and heat treatment has been carried out on a simple parallelepiped geometry. A second manufacturing chain simulation has been performed on an aero-engine vane component which includes the following manufacturing processes: metal deposition, welding, heat treatment, machining and shot-peening. An investment casting simulation under equiaxed cooling of the bottom core vane (BCV) component of the aero-engines vane has been performed. The gap formation and the gap conductance have been studied and implemented in the analyses. The main goal is to investigate the residual stresses in the BCV cast with Inconel 718 material. Two FE solvers (ABAQUS and ProCAST) have been used for validation purposes. An investment casting simulation under directional cooling in a Bridgman furnace of a high pressure turbine blade (HPTB) with CMSX-4 material has been carried out. The effect of the withdrawal velocity on the temperature and the residual stresses of the HPTB cast has been investigated.
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Carrillo, Janice E. "Process improvements for manufacturing excellence." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/29840.
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Åström, Peter. "Simulation of manufacturing processes in product development /." Luleå, 2004. http://epubl.luth.se/1402-1544/2004/56.
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Bose, Prosenjit. "Geometric and computational aspects of manufacturing processes." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28686.
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Two of the fundamental questions that arise in the manufacturing industry concerning every type of manufacturing process are: (1) Given an object, can it be built using a particular process? (2) Given that an object can be built using a particular process, what is the best way to construct the object? The latter question gives rise to many different problems depending on how best is qualified. We address these problems for two complimentary categories of manufacturing processes: rapid prototyping systems and casting processes. The method we use to address these problems is to first define a geometric model of the process in question and then answer the question on that model.In the category of rapid prototyping systems, we concentrate on stereolithography, which is emerging as one of the most popular rapid prototyping systems. We model stereolithography geometrically and then study the class of objects that admit a construction in this model. For the objects that admit a construction, we find the orientations that allow a construction of the object.
In the category of casting processes, we concentrate on gravity casting and injection molding. We first model the process and its components geometrically. We then characterize and recognize the objects that can be formed using a re-usable two-part cast. Given that a cast of an object can be formed, we determine a suitable location for the pin gate, the point from which liquid is poured or injected into a mold. Finally, we compute an orientation of a mold that ensures a complete fill and minimizes the number of venting holes for molds used in gravity casting processes.
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Ho, Ping-Wing. "Discrete event simulation for yarn manufacturing processes." Thesis, University of Huddersfield, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315679.
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El-Sayed, Jacqueline Johnson. "Multi-objective optimization of manufacturing processes design /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841282.
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Lee, Ho Young. "Diagnosing spatial variation patterns in manufacturing processes." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969/122.
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Jin, Ming. "Chart allocation and control techniques for multistage and run-to-run processes /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?IELM%202008%20JIN.
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Li, Yanting. "Monitoring and diagnosing the mean vector and covariance matrix of multistage processes /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?IELM%202008%20LI.
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Lu, Junde. "Model migration based on process similarity /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CBME%202008%20LU.
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Ronnestrand, Clinton. "Using control charts to determine if a process is in statistical process control." Online version, 2009. http://www.uwstout.edu/lib/thesis/2009/2009ronnestrandc.pdf.
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Wong, Yiu-chung. "Outward processing in China and its implications to the economy of Hong Kong." Click to view the E-thesis via HKUTO, 1989. http://sunzi.lib.hku.hk/hkuto/record/B43893260.
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Alshara, Khaled. "Modeling and optimization of the process mean in a serial production system subject to acceptance sampling plans." Diss., Online access via UMI:, 2007.
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Nyembwe, Kasongo Didier. "Tool manufacturing by metal casting in sand moulds produced by additive manufacturing processes." Thesis, Bloemfontein : Central University of Technology, Free State, 2012. http://hdl.handle.net/11462/162.
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Thesis (D. Tech. ( Mechanical Engineering )) - Central University of technology, Free State, 2012In this study an alternative indirect Rapid Tooling process is proposed. It essentially consists of producing sand moulds by Additive Manufacturing (AM) processes followed by casting of tools in the moulds. Various features of this tool making method have been investigated. A process chain for the proposed tool manufacturing method was conceptually developed. This process chain referred to as Rapid Casting for Tooling (RCT) is made up of five steps including Computer Aided Design (CAD) modeling, casting simulation, AM of moulds, metal casting and finishing operations. A validation stage is also provided to determine the suitability of the tool geometry and material for RCT. The theoretical assessment of the RCT process chain indicated that it has potential benefits such as short manufacturing time, low manufacturing cost and good quality of tools in terms of surface finish and dimensional accuracy. Focusing on the step of AM of the sand moulds, the selection of available AM processes between the Laser Sintering (LS) using an EOSINT S 700 machine and Three Dimensional Printing using a Z-Corporation Spectrum 550 printer was addressed by means of the Analytic Hierarchy Process (AHP). The criteria considered at this stage were manufacturing time, manufacturing cost, surface finish and dimensional accuracy. LS was found to be the most suitable for RCT compared to Three Dimensional Printing. The overall preferences for these two alternatives were respectively calculated at 73% and 27%. LS was then used as the default AM process of sand moulds in the present research work. A practical implementation of RCT to the manufacturing of foundry tooling used a case study provided by a local foundry. It consisted of the production of a sand casting pattern in cast iron for a high pressure moulding machine. The investigation confirmed the feasibility of RCT for producing foundry tools. In addition it demonstrated the crucial role of casting simulation in the prevention of casting defects and the prediction of tool properties. The challenges of RCT were found to be exogenous mainly related to workmanship. An assessment of RCT manufacturing time and cost was conducted using the case study above mentioned as well as an additional one dealing with the manufacturing of an aluminium die for the production of lost wax patterns. Durations and prices of RCT steps were carefully recorded and aggregated. The results indicated that the AM of moulds was the rate determining and cost driving step of RCT if procurement of technology was considered to be a sunk cost. Overall RCT was found to be faster but more expensive than machining and investment casting. Modern surface analyses and scanning techniques were used to assess the quality of RCT tools in terms of surface finish and dimensional accuracy. The best surface finish obtained for the cast dies had Ra and Rz respectively equal to 3.23 μm and 11.38 μm. In terms of dimensional accuracy, 82% of cast die points coincided with die Computer Aided Design (CAD) data which is within the typical tolerances of sand cast products. The investigation also showed that mould coating contributed slightly to the improvement of the cast tool surface finish. Finally this study also found that the additive manufacturing of the sand mould was the chief factor responsible for the loss of dimensional accuracy. Because of the above, it was concluded that light machining will always be required to improve the surface finish and the dimensional accuracy of cast tools. Durability was the last characteristic of RCT tools to be assessed. This property was empirically inferred from the mechanical properties and metallographic analysis of castings. Merit of durability figures of 0.048 to 0.152 were obtained for the cast tools. It was found that tools obtained from Direct Croning (DC) moulds have merit of durability figures three times higher than the tools produced from Z-Cast moulds thus a better resistance to abrasion wear of the former tools compared to the latter.
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Mummareddy, Bhargavi. "Additive Manufacturing Processes for High-Performance Ceramics: Manufacturing - Mechanical and Thermal property Relationship." Youngstown State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1629131959379597.
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Scaramuzzino, Giuseppe. "Definition and Standardization of ADS2 Ltd Manufacturing Processes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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L’elaborato realizzato nei sei mesi di tirocinio per tesi svolto presso l’azienda ADS2 Brands Limited con sede a Biggleswade (UK) è il frutto di un lavoro di osservazione, analisi e intervento sui processi produttivi aziendali.
Lo scopo del progetto era quello di definire, ottimizzare e standardizzare i processi produttivi per poi giungere alla stesura di un set di documentazione tecnica da condividere con l’ufficio tecnico, con il project manager e con il plant manager.
L’azienda è specializzata nella realizzazione di componentistica per gli impianti di spillamento delle bevande, quindi si tratta di una produzione fortemente personalizzata.
La principale tecnologia di produzione è quella di stampaggio per iniezione con l’utilizzo di diverse tipologie di materiali termoplastici, ad esempio ABS, PMMA, Polipropilene. A questo processo tecnologico che coinvolge la maggior parte della produzione si affiancano altre tecnologie quali termoformatura, stampa digitale e tradizionale, oltre che alle attività di realizzazione degli stampi.
Sono stati osservati numerosi cicli di fabbricazione, rilevandone tempi, caratteristiche dei materiali, tasso di impiego delle risorse (in termini di operatori, macchinari, attrezzature, materiali) e qualità dei componenti realizzati. Tutti i dati rilevati in fase di analisi sono stati analizzati e confrontati con quelli già presenti sul gestionale Microsoft Dynamics 365.
Di ogni componente, sono state rilevate le criticità in fase di produzione, di altre eventuali lavorazioni o di assemblaggio e si è cercato di fornirne delle soluzioni praticabili.
Molti processi sono stati ottimizzati secondo la filosofia del Lean Manufacturing e si è giunti alla realizzazione del set di documentazione prevista: scheda macchina, scheda di processo e scheda di prodotto.
A margine di ciò sono state proposte delle soluzioni per quanto riguarda l’organizzazione del magazzino, l’identificazione dei tool e l’impiego di risorse per ridurre i lead time.
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Zhang, Feng. "Identifying nonlinear variaiton patterns in multivariate manufacturing processes." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1373.
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This dissertation develops a set of nonlinear variation pattern identification methods that are intended to aid in diagnosing the root causes of product variability in complex manufacturing processes, in which large amounts of high dimensional in-process measurement data are collected for quality control purposes. First, a nonlinear variation pattern model is presented to generically represent a single nonlinear variation pattern that results from a single underlying root cause, the nature of which is unknown a priori. We propose a modified version of a principal curve estimation algorithm for identifying the variation pattern. Principal curve analysis is a nonlinear generalization of principal components analysis (PCA) that lends itself well to interpretation and also has theoretically rich underpinnings. The principal curve modification involves a dimensionality reduction step that is intended to improve estimation accuracy by reducing noise and improving the robustness of the algorithm with the high-dimensional data typically encountered in manufacturing. An effective visualization technique is also developed to help interpret the identified nonlinear variation pattern and aid in root cause identification and elimination. To further improve estimation robustness and accuracy and reduce computational expense, we propose a local PCA based polygonal line algorithm to identify the nonlinear patterns.
We also develop an approach for separating and identifying the effects of multiple nonlinear variation patterns that are present simultaneously in the measurement data. This approach utilizes higher order cumulants and pairwise distance based clustering to separate the patterns and borrows from techniques that are used in linear blind source separation. With the groundwork laid for a versatile flexible and powerful nonlinear variation pattern modeling and identification framework, applications in autobody assembly and stamping processes are investigated. The pattern identification algorithms, together with the proposed visualization approach, provides an effective tool to aid in understanding the nature of the root causes of variation that affect a manufacturing process.
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Kagioglou, Michail. "Adapting manufacturing project processes into construction : a methodology." Thesis, University of Salford, 1999. http://usir.salford.ac.uk/26747/.
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The need for improvements in the construction industry in the UK has been reported through a succession of Government and Institutional reports, illustrating the problem areas. The area of project processes in manufacturing has been found to have great similarities with its equivalent (design and construction) in the construction industry. This has led to co-ordinated efforts in improving the construction industry project processes by considering 'Construction as a Manufacturing Process.' Those efforts concentrated in adapting the manufacturing project process elements into construction. However, the methodology needed to adapt those processes has not been considered. This was presented as an opportunity to develop an original and novel methodology for the Adaptation of MAnufacturing Project Processes Into Construction (AMaPPIC). The aforementioned need combined with the author's experience in both the manufacturing and construction industries were the catalysts for the formulation of the research. A case study research strategy was used to undertake the research, for the discovery, building and testing of the AMaPPIC methodology. A number of research methods were employed to collect data for the research. The necessary literature in business process management, manufacturing NPD (new product development), and design and construction was combined with a number of informing case studies for the discovery and building of the AMaPPIC methodology. The methodology consists of 14 stages, which consider the identification and demonstration of a need for adapting project processes into construction to the final 'existence' and continuous improvement of the adapted process within an organisation. The GPT case study was used to test the AMaPPIC methodology in a 'live' project within the company. The results of the case study were used to further define and improve the methodology by examining its applicability in the Poole project. The resulting AMaPPIC methodology provides an original, prototypical solution to adapting manufacturing project processes into construction.
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Batley, A. "Sustainable improvement processes for 21st century manufacturing enterprises." Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494572.
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Newman, J. D. "Advanced manufacturing processes for the production of biosensors." Thesis, Cranfield University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284870.
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Stern, Michael L. S. M. Massachusetts Institute of Technology. "Aligning design and development processes for additive manufacturing." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100354.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 83-88).
Rapid Prototyping has transitioned from only being able to produce delicate prototypes to being capable of producing robust production parts. As part of this transition, it has been renamed Additive Manufacturing (AM). As a true manufacturing technology, it has become important to deliberately design parts for Additive Manufacturing, and research has begun in how best to achieve this. This thesis explores the background of Additive Manufacturing, the growth in its use as a manufacturing technology, and the advantages and challenges of the technology. Following background information, this thesis progresses to different design approaches and technologies that promise to be effective when paired with AM. A design methodology using topology optimization is proposed, detailed and then tested on two case studies. The first case is a high-speed mirror for imaging and the second case is an aircraft bracket for the 2013 GrabCAD-GE design challenge. This thesis also includes an examination of the implementation of the proposed methodology on these case studies and the resulting designs. The design from both case studies achieved a greater than 60% weight reduction through the use of design methodology tailored for AM. The final section of the thesis shifts from the design process to the development process where the impact of AM is examined. In order to gain an understanding of the influence that Additive Manufacturing has on production, this thesis includes a synthesis of the literature from Additive Manufacturing as well as Design and Management. The benefits are approached from an economic perspective, reviewing the first order benefits that have been extensively studied and then progressing to the second order benefits, and indirect benefits, which have not been examined in detail before. To understand the full effect of Additive Manufacturing on product development, the consideration of advantages such as high fidelity prototypes, decreased risk, faster time to market and late stage design flexibility are assessed.
by Michael L. Stern.
S.M.
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Siu, Tsz-Sin 1977. "Cycle to cycle feedback control of manufacturing processes." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/89308.
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Ezolino, Juan Stefano. "Design for automation in manufacturing systems and processes." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104311.
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Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2016. In conjunction with the Leaders for Global Operations Program at MIT.Thesis: S.M. in Engineering Systems, Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016. In conjunction with the Leaders for Global Operations Program at MIT.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 88-89).
The Widget' industry has changed significantly over the last 20 years. Although Company A benefited from their historically strong market position for a long time, the market share of widgets has, at this point, been evenly divided between Company A and Company B. There is therefore market pressure for Company A to reassess the way it does business to be more competitive. Automation initiatives in the Widget industry have historically been slow to be implemented, and there has been hesitation to change the way widgets and their parts are designed and manufactured due to the complexity of the widget product. But in order to work in a more competitive global market, companies must question many of the established assumptions regarding their products in order to achieve efficiency gains and improve safety standards in their production system. The ultimate goal of the project was to align the design, manufacturing, and business processes with new technology capabilities and the goals of the company. By doing this, the cost of producing a widget would be decreased, while increasing in-process quality and repeatability. This thesis focuses on ways in which to show the value of improving the design of a widget to enable more efficient production systems, while ensuring the risk of injury to the mechanics is continuously lowered through increased process control and standardization. In order to understand what it means for engineers across the company to design parts and assemblies with automated manufacturing processes in mind, a list of high-level technical design principles needed to be developed. A group of 17 design and production engineers was assembled for a workshop, representing all of the widget programs, R&D, Product Development, Fabrication, Engineering Operations, Manufacturing Operations, and IT. Through two days of activities, a list of ten principles was developed that could be applied to any widget part or assembly that was intended to be manufactured through automation. After the Design for Automation (DfA) principles were established and agreed-upon, it was necessary to find ways to effectively implement new tools and methodologies into the established design process.
by Juan Stefano Ezolino.
M.B.A.
S.M. in Engineering Systems
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Holtz, Heath M. (Heath Mikal). "Re-sourcing manufacturing processes in metal forming operations." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34859.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Manufacturing Program at MIT, 2005.Includes bibliographical references (p. 75-76).
Deciding which activities to conduct in-house and which to outsource has become increasingly important due to its implications on a company's supply chain and overall business model. A number of factors can lead a company to outsource manufacturing processes. As a result of this outsourcing, the supply chain can become very complex and overwhelming to manage. This thesis will analyze this situation from the perspective of one manufacturer, American Axle and Manufacturing, Inc. (AAM). AAM's Metal Formed Products (MFP) Division currently has a number of challenges: rising steel prices, fixed labor costs and declining sales. All these factors have significantly impacted profitability, forcing senior management to take a comprehensive look at the division and consider developing a plan to improve divisional operations. As a part of this plan, MFP Division's senior management asked for a thorough look into all of the manufacturing processes performed by the division both internally and by outside suppliers. In addition to identifying the processes and suppliers, senior management sought to highlight opportunities for improving the process flow through the re-sourcing of manufacturing processes. This project develops a framework to analyze and evaluate these re-sourcing decisions. This framework employs a five-step approach and incorporates a number of diverse analytical tools. Process flow mapping provided a tool to visually highlight the best opportunities to resource. In addition to a visual representation, process flow mapping also provided the data to financially evaluate alternatives. Strategic and market factors were identified in order to target and prioritize re-sourcing efforts.
(cont.) This framework provides a structure for sourcing decisions that balances the financial and strategic concerns. The project concluded in a $2M investment to re-source heat treating to AAM facilities.
by Heath M. Holtz.
S.M.
M.B.A.
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Key, Ross A. "Automated manufacturing processes for secondary structure aerospace composites." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33572/.
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As projected manufacturing rates for commercial aircraft increase to levels of multiple ship sets per day from individual manufacturing facilities, GE Aviation have expressed the need for a shift in composites secondary structure manufacturing philosophy. Traditional manufacturing processes tend to be touch labour intensive and hence costly. The manual placement of large numbers of individual ply profiles, lengthy debulking operations and complex cure cycles, result in excessive component lead times and manufacturing costs. As a result, direct labour cost is a major factor in the total economies of production processes. The implementation of industrial robotics has proved highly successful in automotive manufacturing, and various methods for automating individual aspects of the composites manufacturing process have been suggested. Technical cost modelling has been used to anticipate the production costs of a prototype secondary structure component, as supplied by GE Aviation, through direct simulation of the existing manufacturing process. This work has clearly highlighted the potential for cost and cycle time reductions if process automation can be successfully introduced. Observation of the existing manufacturing process has allowed three alternative manufacturing scenarios to be considered with respect to cost-effectiveness and feasibility, whilst highlighting long term cost benefits. Investigations have been undertaken to identify and evaluate alternative material and processing methodologies ranging from resin infused woven dry fabrics to UD prepreg tape and tow. In addition, candidate processing routes have been systematically evaluated using design of experiments techniques, which focussed on assessing the feasibility and technology readiness of robotic deposition and consolidation methodologies, including pick and place and debulking. Process automation in these areas has the potential for total component cost and cycle time reductions in the order of 2.8 to 21.6 and 0.6 to 63.4 per cent respectively. The quasi-static mechanical testing of a range of face sheet materials has provided a performance assessment based on tensile, compressive and shear properties and laminate Vf. Findings suggest that materials offering increased suitability for automation typically have reduced mechanical performance when compared to candidate prepregs; tensile modulus and strength reductions of 5 and 34 per cent were reported when comparing a 6k woven 2X2 twill fabric and equivalent prepreg respectively. Furthermore, 26 and 4 per cent reductions in tensile modulus and 38 and 40 per cent reductions in tensile strength were observed for 179 and 318gsm UD NCF, when compared with a candidate UD prepreg. Data has also been presented on the effect of varying the traditional consolidation frequency and methodology. While earlier findings suggest that debulking has little effect on the laminate tensile modulus; ply compaction level varies considerably. Furthermore, it has been shown that on-the-fly consolidation, using a robotically mounted, roller-based end effector has the advantages of mechanical performance retention, cycle time reduction and repeatable laminate post cure thickness. In addition, when compared with candidate woven and UD prepreg laminates manufactured using the traditional vacuum bagging approach; equivalent tensile modulus, strength and fibre volume fraction have been observed and with less variability. Handling characteristics inherent to vacuum and needle grippers, including pickup performance, defined as the pickup or holding force required to overcome fabric weight, shear force performance; the maximum force that can be exerted on the fabric before the onset of slip, and the accuracy with which non-rigid-materials (NRMs) can be handled, have also been considered. The achievable positional accuracy of robotically pick and placed prepreg plies greatly exceeds that of dry fabrics in all cases and with less variability, irrespective of the gripping mechanism used. Vacuum grippers exhibit more uniform positional error and increased positional accuracy when handling dry fabrics, whilst needle grippers outperformed the vacuum alternative when handling prepregs, irrespective of form. Robotic pick and place solutions offer low variability in ply positional error with a guaranteed placement accuracy of ±0.8mm and ±2.3mm for prepregs and dry fabrics respectively. Characterisation of the gap type defect and butt and overlapping joining methodologies has provided a performance trend based on ply positional error. Quasi-static mechanical testing has revealed that laminates with equivalent tensile modulus to an un-spliced control could be achieved. However, significant reductions in the tensile strength and an increase in overall laminate thickness and thickness variation highlighted the negative effect of ply splicing on laminate performance. However, it has been shown that a robotic placement accuracy of ±0.8mm gives rise to acceptable tensile strength reductions in candidate prepreg laminates. The up-scaling of laminate level robotic manipulators has been discussed and addressed in conjunction with the commissioning of a flexible robotic manufacturing cell, facilitating the manufacture of full-scale secondary structure aerospace components. Comparisons have been made between a benchmark prepreg panel, manufactured using traditional manual methods and alternative dry fabric and prepreg panels manufactured using increased levels of process automation. In each case, manufacturing feasibility, mechanical performance and component geometric accuracy have been assessed. It has been shown that there are significant advantages to be gained from the implementation of robotic automation within the traditional manufacturing process. Component cost and cycle time reductions, coupled with the processing and performance advantages and increased suitability to automation of woven dry fibre materials are clear. Findings which support a key driver of this project, which seeks to justify alternative dry fabrics as a viable alternative to traditional prepreg broadgoods for the manufacture of secondary structure aerospace components.
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Pihnastyi, O. M., and K. M. Bondarenko. "Analysis of the models transition processes controlled manufacturing." Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/27377.
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Lu, Yufeng. "Scheduling of Wafer Test Processes in Semiconductor Manufacturing." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/10153.
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Scheduling is one of the most important issues in the planning of manufacturing systems. This research focuses on solving the test scheduling problem which arises in semiconductor manufacturing environment. Semiconductor wafer devices undergo a series of test processes conducted on computer-controlled test stations at various temperatures. A test process consists of both setup operations and processing operations on the test stations. The test operations occur in a specified order on the wafer devices, resulting in precedence constraints for the schedule. Furthermore, the assignment of the wafer devices to test stations and the sequence in which they are processed affects the time required to finish the test operations, resulting in sequence dependent setup times. The goal of this research is to develop a realistic model of the semiconductor wafer test scheduling problem and provide heuristics for scheduling the precedence constrained test operations with sequence dependent setup times.
A mathematical model is presented and two heuristics are developed to solve the scheduling problem with the objective of minimizing the makespan required to test all wafer devices on a set of test stations. The heuristic approaches generate a sorted list of wafer devices as a dispatching sequence and then schedule the wafer lots on test stations in order of appearance on the list.
An experimental analysis and two case studies are presented to validate the proposed solution approaches. In the two case studies, the heuristics are applied to actual data from a semiconductor manufacturing facility. The results of the heuristic approaches are compared to the actual schedule executed in the manufacturing facility. For both the case studies, the proposed solution approaches decreased the makespan by 23-45% compared to the makespan of actual schedule executed in the manufacturing facility. The solution approach developed in this research can be integrated with the planning software of a semiconductor manufacturing facility to improve productivity.Master of Science
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Batley, Alun. "Sustainable improvement processes for 21st century manufacturing enterprises." n.p, 2003. http://ethos.bl.uk/.
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Mestry, Sanket Dilip. "Software tool for analysis of manufacturing processes (STAMP)." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2661.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains xii, 81 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 73-74).
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Fung, Ho Ki. "Synthesis and development of manufacturing processes for biopharmaceuticals /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?BIEN%202003%20FUNG.
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Wong-Swanson, Belinda Gum-Hung. "Energy analysis of manufacturing processes on the moon." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185672.
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A methodology for the energy analysis of high temperature lunar manufacturing processes is presented. The Moon's environment creates unique thermodynamic and heat rejection problems due to the absence of an atmosphere and large ambient temperature swing as it goes from lunar day to lunar night; it is a perfect vacuum at the surface. The methodology combines availability analysis, the Pinch technology and a mathematical heat rejection model to minimize energy requirement and the lift-off mass from earth. The availability analysis is used to identify process irreversibilities and to determine the quality of energy from various exit streams. The Pinch technology is used to identify hot and cold streams for potential process heat integration. The heat rejection model is used to optimize the radiator area with temperature as the driving factor. The methodology presented allows one to identify all power consumption, production and rejection in the process, and then determine the feasibility of heat and work integration without a significant mass penalty. It provides a means to design a power system to minimize waste energy. This would result in reduction of the power requirement, cost of power and the power system's mass. The hydrogen reduction of ilmenite process for oxygen production on the Moon is used as a case study to demonstrate the energy analysis methodology. The study was limited to the reduction and electrolysis processes. The availability analysis estimated that the two processes required 56 kW to meet sensible heat and heat of reaction demands but produced 53 kW of process irreversibilities. This 53 kW of unavailability included 9.4 kW of energy potential in the product solid stream and product oxygen stream. The Pinch technology found that the product solid stream and product oxygen stream may be split to help meet the heating demands of the feed ilmenite stream. This would reduce the 56 kW of power demand by 24%. If oxygen were to be brought from 1273 K to 300 K, its entire heat content may be recovered and heat rejection is eliminated. The heat exchanger area requirement is estimated to be more than ten times the radiator area if the radiator were operated at 1273 K.
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Cryan, Dan David III. "Designing internal logistics processes for new manufacturing site." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122582.
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Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2019, In conjunction with the Leaders for Global Operations Program at MITThesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2019, In conjunction with the Leaders for Global Operations Program at MIT
Cataloged from PDF version of thesis.
Includes bibliographical references (page 80).
The Boeing Company is the world's largest aerospace company and is constantly evaluating improvement opportunities to the production system. It is of ongoing interest to the company to have to tools to assess new manufacturing sites. Among the required tasks for such an effort, engineers must identify the processes and capabilities that will be needed. A critical element of this study is the system of internal logistics processes that could manage the flow of parts and material throughout a site. Planning the capacity of these processes is difficult when many of the parameters are uncertain and yet to be determined. This thesis proposes a method for estimating capacity requirements of internal logistics processes by employing the concepts of queuing theory and Little's Law. Using this methodology, a process model was developed and validated by discrete event simulation to provide process planners with an understanding of the relationship and importance of numerous parameters. This understanding allows planners and management to assess the capacity requirements of the processes in terms of projected costs and performance. Values of wait times predicted by the proposed model were in strong agreement with values observed from simulation (R-squared of 96.4%; MAPE of 14.9%) suggesting that the proposed methodology represents an easy-to-use and accurate representation of process parameters. In order to improve the applicability of capacity recommendations for Boeing, further refinement is needed of underlying process parameters as well as cost modeling of threshold parameters (k and pn_max).
by Dan David Cryan, III.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Civil and Environmental Engineering
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D'ANTONIO, GIANLUCA. "Manufacturing Execution Systems for lean, adaptive production processes." Doctoral thesis, Politecnico di Torino, 2016. http://hdl.handle.net/11583/2641291.
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In order to deal with global competition, industries have undertaken many efforts directed to improve manufacturing efficiency. From a broad perspective, the adopted approaches could be classified in two categories:
1. the simplification of manufacturing processes and relative control systems, leading to lean manufacturing methododologies and techniques;
2. the massive deployment of information tools and computational algorithms, aiming to plan and control all the activities in detail, in spite of system complexity.
For several years, these two approaches have been assumed to be mutually exclusive; nevertheless, information collection and analysis are mandatory to define improvement strategies and assess their impact; therefore, the deployment of lean manufacturing methodologies cannot exclude the integration of Information Technology (IT) tools.
The aim of this work is to investigate on methodologies and techniques adoptable to improve the efficacy of Manufacturing Execution Systems (MES), a class of software that allows data exchange between the shop-floor and the organizational levels, enabling the implementation of the lean manufacturing approach.
Today, the feedback information in the available MES mainly consists in key performance indicators, such as cycle time, work in process and resources utilization. Beside this, MES requires the integration of functionalities for process monitoring and control, aiming at the reduction of wastes and supporting continuous improvement. Hence, mathematical techniques able to analyze data in real-time and provide useful information to adaptively control the process are studied in this work. To provide the evidence of the feasibility and effectiveness of the approach, as well as the independence from any specific manufacturing technology, different case studies, both in the fields of subtractive and additive manufacturing, have been developed. In the former, a technique for the automatic alignment of a spur gear has been studied: geometrical measurements are acquired and analyzed in real-time to provide the values for two feasible part rotations resulting in the gear configuration with minimum positioning error. Such gears are manufactured for applications in aeronautics, and the deployment of this automation system is particularly significant because of the tight tolerances to be satisfied. The latter case study deals with a Fused Deposition Modeling process: an algorithm able to monitor part surface accuracy and identify defects has been developed. This methodology allows to evaluate in real-time whether the quality of the part is satisfactory or not; in case of negative response, the process can be stopped avoiding material loss. The implemented techniques enable product quality improvement, as well as the reduction of wasted material and time. Nevertheless, the deployment of such information only for process control purposes is restrictive; a framework to use this knowledge for supporting the design and the continuous improvement of a product or a process is presented.
Furthermore, two case studies have been dealt to extend the application of MES tools from manufacturing operations to ancillary services. The first one is in the field of automated warehouses: a combined approach made of mathematical models and simulations has been developed. Analytical tools have been defined to evaluate the average performance of a system in simple, pre-determined situations; conversely, the simulation tool aims at a higher detail level of assessment, since in the real shop-floor deployment, different, composite storage and retrieval activities can take place. In the second case-study, mathematical models and simulation are used to support the re-design of a manufacturing process; the focus is on the transport of items through the line, performed by automated vehicles. The mathematical model has been developed to identify the optimal layout of the workstations; simulations are used to evaluate the tasks to be performed by the automated vehicles and the resulting performance. In both the applications, the deployment of simulation tools allows to evaluate complex or even unexpected scenarios by predicting the behavior of a system, preventing criticalities, and evaluating the impact of a change in the process. The management criteria can be adapted according to the features of the real situation to be faced; this leads to better exploit the available resources, to improve productivity and identify waste sources, consistently with the lean paradigm.
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Smith, Scott G. "Quick response tool and die manufacturing." Menomonie, WI : University of Wisconsin--Stout, 2005. http://www.uwstout.edu/lib/thesis/2005/2005smiths.pdf.
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He, Xuejian. "Haptic modeling for virtual manufacturing." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40987978.
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Sun, Hongyue. "Synergistic Modeling of Advanced Manufacturing Processes with Functional Variables." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/77881.
Full textAbstract:
Modern manufacturing needs to optimize the entire product lifecycle to satisfy the customer needs. The advancement of sensing technologies has brought a data rich environment for manufacturing and provide a great opportunity for real-time, proactive quality assurance. However, due to the lack of methods for analyzing heterogeneous types of data, the transformation of data to information and knowledge for effective decision making in manufacturing is still a challenging problem. In particular, functional variables can represent the in situ process conditions and rich product performance information, and are widely encountered in various manufacturing processes. In this dissertation, I will focus on modeling of manufacturing processes with in situ process (functional) variables, and integrating these functional variables and other measured variables for the manufacturing modeling.
The modeling is explored by extracting informative features through the integration of multiple functional variables, functional variables and offline setting variables, and quantitative and qualitative quality variables. After an introduction in Chapter 1, three research tasks are investigated. First, a functional variable selection problem is studied in Chapter 2 to identify the significant functional variables as well as their features in a logistic regression model. A hierarchical non-negative garrote constrained estimation method is proposed. Second, the quality-process relationships for scalar offline setting variables, functional in situ process variables, and manufacturing quality responses are studied in Chapter 3. A functional graphical model that can integrate functional variables in a graphical model is proposed and investigated. Third, the quantitative and qualitative quality responses are jointly modeled with scalar offline setting variables and functional in situ process variables in Chapter 4. A functional quantitative and qualitative model is proposed and investigated. Finally, I summarize the research contribution and discuss future research directions in Chapter 5.
The proposed methodologies have broad applications in manufacturing processes with functional variables, and are demonstrated in a crystal growth process with multiple functional variables (Chapter 2), a plasma spray process with multiple scalar and functional variables (Chapter 3), and an additive manufacturing process called fused deposition modeling with quantitative and qualitative quality responses (Chapter 4).Ph. D.
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Adebayo, Adeyinka. "Characterisation of integrated WAAM and machining processes." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8258.
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This research describes the process of manufacturing and machining of wire and arc additive manufactured (WAAM) thin wall structures on integrated and non¬integrated WAAM systems. The overall aim of this thesis is to obtain a better understanding of deposition and machining of WAAM wall parts through an integrated system. This research includes the study of the comparison of deposition of WAAM wall structures on different WAAM platforms, namely an Integrated SAM Edgetek grinding machine, an ABB robot and a Friction Stir Welding (FSW) machine. The result shows that WAAM is a robustly transferable technique that can be implemented across a variety of different platforms typically available in industry. For WAAM deposition, a rise in output repeatedly involves high welding travel speed that usually leads to an undesired humping effect. As part of the objectives of this thesis was to study the travel speed limit for humping. The findings from this research show that the travel speed limit falls within a certain region at which humping starts to occur. One of the objectives of this thesis was to study the effect of lubricants during sequential and non-sequential machining/deposition of the WAAM parts. Conventional fluid lubricants and solid lubricants were used. In addition, the effect of cleaning of deposited wall samples with acetone was also studied. A systematic study shows that a significant amount of solid lubricant contamination can be found in the deposited material. Furthermore, the results indicate that even cleaning of the wire and arc additive manufactured surfaces with acetone prior to the weld deposition can affect the microstructure of the deposited material.
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Singh, Karmjit. "A framework for sustainability performance assessment for manufacturing processes." Thesis, Federation University Australia, 2019. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/169827.
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Sustainable manufacturing methods make it possible to develop products in ways which minimize negative environmental impacts, conserve energy and save natural resources whilst being economically sound. The concepts of sustainability in manufacturing being are still fairly broad, in scope, and need to be more focused and firmly established at the process, machine or factory levels. This project proposes a structure for manufacturing with a main objective to develop a sustainability framework which encompasses various production processes. Structured information models for the seamless flow of information across the design and manufacturing domains, for selected manufacturing processes, are defined. The thesis work identifies key performance indicators (KPIs) for the assessment of manufacturing sustainability and performs analysis of selected unit manufacturing processes and their sub-processes with the aim of proposing a methodology for determining science-based measurements of the manufacturing processes affecting these KPIs. The theoretical foundations established are then used to develop a model that could evaluate sustainability of selected manufacturing processes and their respective process plans providing a basis for inter-process comparison and selection of the most sustainable process plan. The proposed framework is presented in form of a manufacturing planning computer-based package which is designed to to consider different influencing factors such as product information, part geometry, material related physical and processing properties and the manufacturing equipment operating data. The thesis presents a number of case studies which have been published in international journals. The case studies present estimates of the manufacturing sustainability KPIs for a number of production methods. These estimates have been verified with available shop floor data. The work in the thesis makes it possible to establish manufacturing industry equipped to deal the challenges of the future when sustainability will be the major factor up on which the quality of success will be determined.Doctor of Philosophy
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Samson, Allan L. "Understanding and improving the inefficiencies of an engineering change management system using the action research model." [Denver, Colo.] : Regis University, 2005. http://165.236.235.140/lib/ASamson2005.pdf.
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Ahn, Song-Jun. "The impacts of automation equipment at Chung-Woo Industrial Co., Ltd." Online version, 1998. http://www.uwstout.edu/lib/thesis/1998/1998ahns.pdf.
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Wink, Eric A. "Proposed change of work in process (WIP) inventory for the polishing department at APN, Incorporated." Online version, 2003. http://www.uwstout.edu/lib/thesis/2003/2003winke.pdf.
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