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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.
31

Desenvolvimento do processo de estampagem para miniaturização de motores / Micro deep drawing applied in the fabrication of micromotors

Boff, Uilian January 2012 (has links)
O processo de microestampagem permite a fabricação de peças ou microcomponentes, podendo ser aplicado a diversas áreas da engenharia. Logo, este trabalho tem por objetivo desenvolver um micromotor de passo e avaliar os efeitos da miniaturização de seus componentes. A simulação computacional foi utilizada neste trabalho de forma a avaliar os defeitos surgidos com a miniaturização, através do software de elementos finitos DYNAFORM com “solver” LS-DYNA. O material empregado na carcaça foi o aço de baixo carbono ABNT 1010 e o aço inoxidável ABNT 304, e para o núcleo magnético do micromotor, composto pelo rotor e estator, utilizou-se o aço elétrico ABNT 35F 420M. A simulação computacional, além de identificar os problemas oriundos da miniaturização dos componentes, também foi utilizada para otimizar as ferramentas de microestampagem, demonstrando desta forma ser uma grande aliada para o desenvolvimento do processo. O processo de corte convencional em matriz não foi aplicado no corte do rotor e do estator, pois produziu defeitos como empenamento e rebarbas. Ao invés disso, empregou-se o processo de corte por eletroerosão a fio, que produziu peças planas e superfícies lisas. / The process of micro deep drawing is a micro-technology which allows the fabrication of microcomponents and can be applied to various fields of engineering. This study aims to develop the components of a micromotor step using this technology and to evaluate the effects of the microfabrication of the motor frame, rotor and stator. A computer simulation was carried out in order to evaluate miniaturization of the components trough the finite element software DYNAFORM with “Solver” LS-DYNA. The material used in the motor housing was low carbon steel ABNT 1010 and stainless steel ABNT 304. However, in magnetic core, comprising the rotor and stator, the electric steel ABNT 35F 420M was employed. Micro deep drawing tools were developed based on the results obtained through simulation is a great ally to create microcomponents. The cutting process in the matrix was not employed to cut de rotor and the stator, because it produced defects such as warping and butts along the surface. Instead, wire cutting spark erosion was used and resulted in hat part and surfaces.
32

Caracterização e comparação dos procedimentos de obtenção da curva limite de conformação e das características de estampagem dos aços inoxidáveis DIN 1.4509 e AISI 321. / Characterization and comparison of the procedures for obtaining the Forming Limit Diagram and the deep drawing characteristics of DIN 1.4509 and AISI 321 stainless steels.

Caio de Paula Camargo Pisano 29 June 2017 (has links)
Com a grande demanda do mercado brasileiro, e mundial, por desenvolvimento de novas tecnologias, redução de custos e de complexidade, os processos industriais buscam cada vez mais alternativas inovadoras. Para que essa evolução seja possível, é fundamental que todos os componentes da cadeia industrial também se desenvolvam, tornando assim as matérias primas, como aços, polímeros, alumínio, e outros metais que estão na base da cadeia, um grande foco de estudos. A indústria siderúrgica, em específico, vem buscando este desenvolvimento nos últimos anos, trabalhando principalmente no desempenho que os materiais terão nos processos industriais, tais como estampagem, soldagem e muitos outros. O processo de estampagem requer o desenvolvimento destes materiais, já que este solicita matérias primas com um bom desempenho mecânico, capaz de absorver possíveis variações e dificuldades que existem em uma linha de produção industrial. Para que este objetivo seja atingido, deve-se dedicar tempo e recursos para encontrar a combinação ideal entre pesquisa e processo produtivo e, assim, otimizar as características mecânicas e químicas dos materiais para o desenvolvimento da cadeia industrial. No contexto da estampagem há um bom indicativo para prever qual será o desempenho de um material: a Curva Limite de Conformação (CLC). Neste presente trabalho os conceitos da CLC serão discutidos, e aplicados a dois aços inoxidáveis distintos, um da família ferrítica (DIN 1.4509) e outro da família austenítica (AISI 321). Além disso, também serão abordadas as principais características metalúrgicas e mecânicas, correlacionadas à estampagem, destes materiais e as principais formas de utilizar estas informações na prática industrial com o objetivo de aperfeiçoar o desempenho do material nos processos e principalmente, quando possível, promover a migração de uma liga austenítica, por uma liga ferrítica, com o objetivo de redução e estabilidade nos custos. / With the increase of the market demand, both in Brazilian, and in the world, for the development of new technologies, cost and complexity reduction, the industrial processes have been investigating for innovative solutions. In order to this evolution to take place all industrial chain players would have to develop. Therefore all raw materials, such as steels, polymers, aluminum and other metals are in evidence to become the focus of investigation. The steel industry, in particular, has been searching for this evolution over the last years, working in their processes with the goal to increase the performance of the grades on the industrial processes, such as deep drawing, welding, and many others. The deep drawing process is a great motivator to the development of the steels, since it requires a high mechanical performance from the material, to absorb possible variations and difficulties which may occur in an industrial production line. In order to achieve this goal, time and resources must be spent to find the perfect combination between research centers and production processes, optimizing the chemical and mechanical characteristics of the steels, so the development of the whole chain can also advance. Within the deep drawing field of study, a good indicative to predict the material\'s performance is the Forming Limit Diagram (FLD) and in this work the concepts of these FLD\'s will be discussed and applied to two stainless steel grades: a ferritic stainless steel (DIN 1.4509) and an austenitc stainless steel (AISI 321). In addition, the main metallurgical and mechanical properties of these materials, related to the deep drawing, will be approached along with the best ways to apply this kind of information to the industrial practices, in order to increase the material performance and, whenever possible change the austenitic stainless steel to the ferritic stainless steel, in order to reduce and keep the costs stable.
33

Výroba víka kotlového grilu / Production of grill lid

Míka, Tomáš January 2017 (has links)
The thesis is focused on the design of the production of kettle grill lid from steel 11 305 (1.0338) with a constant wall thickness of 1 mm and a series of 10 000 pcs/year. For the selected method of manufacture by conventional drawing, technological calculations were performed. Depending on the diameter of the blank, maximum force and other parameters, the tool and the machine were designed. The tool is a single-operation drawing tool with a blank holder and a rib around the perimeter. These functional parts, together with the drawing punch and drawing die, are made of surface-treated cementitious steel 14 220 (1.7131). The drawing tool is clamped into a CBA 250 hydraulic press with a nominal force of 2 500 kN, where the blank holder is controlled by an additional device at the bottom of the press.
34

Výroba subkomponentu podvozkového kulového kloubu / Production of subcomponent for the chassis ball joint

Liškář, Ladislav January 2018 (has links)
The thesis deals with the design of a technological process for the production a rotationally symmetrical component, which is part of the body for the chassis ball joint of a passenger car. Thesis was developed on request and in cooperation with THK RHYTHM Automotive Czech a.s. On the basis of a literary study, a technological process consisting of 10 operations was designed and elaborated. For the prototype production of the component, a four-column hydraulic press SHPFS 250, with a nominal force 2500 kN, was selected and price offer were prepared. For each of ten operations a prototype tool was designed and prepared assembly drawings. To reduce costs, a single die set was designed to allow all tools to be clamped. The total cost of acquisition of the prototype hydraulic press and tools was set at CZK 2,672,950.
35

Optimalizace metod hodnocení fosfátovacích lázní / Optimalisation of evaluation methods for phosphating bathes

Brzuchańská, Anna January 2008 (has links)
This work deals with phosphating technology of steel. In theoretical part are summarized facts about conventional phosphating process, including steel surfaces pretreatment. In the next chapter the latest contemporary technology of phosphating is discussed, i.e. electrolytic phosphating. This chapter contains principles and characteristics of this technique. Than follow comparisons of electrolytic phosphating and conventional process, concerning economical and ecological aspects. In experimental part is firstly stated nowaday situation of process analyses of phosphating bath for electrolytic phosphating. Intention of experimental part is finding of analytical technique which can be used in operating conditions of phosphating production line. Next chapter render an account of all analytical techniques – measuring of density, refractive index, conductance, reduction potential, pH, turbidity and determination of sulphate, iron and phosphate by indicator papers. Discussion of all results leads to conclusions on tested techniques in connection with practical use in operating conditions of phosphating production line and recommendations for use of individual analytical techniques.
36

Návrh technologie komplexní výroby součásti "Krytka PC skříně" / Technology project for general production of the "PC-box cover"

Křivý, Drahoš January 2011 (has links)
The project, which was done within the scope of engineering’s study shows the proposal of new technology and production organization of a part “PC cover” – a piece done by deep drawing technology from steel sheet of material 11 321. The study shows some of production operations such as cutting, bending, drawing and shearing, included production method solving. In the project were solved also necessary technological calculations and constructional drafts of forming tool. The whole work covers a complex solution of problems related to production of PC cover together with technological disposition of workplace which represents effective layout, distribution and designing of workplace and machines, used for production of the part in a workshop
37

Maziva vhodná pro tažení nerezavějící oceli / Suitable lubricants for deep drawing of stainless steel

Doležal, Jan January 2013 (has links)
This thesis solves problems of design and construction of testing equipment for testing lubricants for deep drawing and experimental evaluation of suitability of different types of lubricants for specified tests conditions. Most of all it is about finding environmentally friendly lubricant which would provide similar results as lubricants containing chlorine compounds when drawing a stainless austenitic Cr-Ni steel 1.4301. As for lubricants provided for testing by leading home and abroad manufacturers, the ATLAS 3374-140 from Quaker Chemical and the WISURA ZW 3356 from FUCHS, were evaluated as the most suitable environmentally friendly lubricants.
38

Technologie výroby víka tvářením / Technology of production cover by forming

Hansen, Petra January 2014 (has links)
Master´s thesis project elaborated within the scope of Master´s degree submits a proposal of manufacture technologies for complicated components with the transition of an elliptical shell into a rectangular shape. Material: Aluminium EN: AW-3003, thickness 2 mm. Estimated annual production: 80 000 pieces. Drawing tool with blankholder was designed based on calculations and literature study of deep drawing. The drawing operation is performed by a hydraulic press ZH 50 with a rated power of 500 kN. The drawing tools are made from tool steel 1.2379 (19 573). Proposal of suitable technologies respectively drawing proces was verified by simulation program FormingSuite and PAM-STAMP.
39

A novel approach towards a lubricant-free deep drawing process via macro-structured tools

Mousavi, Ali 22 April 2020 (has links)
In today’s industry, the sustainable use of raw materials and the development of new green technology in mass production, with the aim of saving resources, energy and production costs, is a significant challenge. Deep drawing as a widely used industrial sheet metal forming process for the production of automotive parts belongs to one of the most energy-efficient production techniques. However, one disadvantage of deep drawing regarding the realisation of green technology is the use of lubricants in this process. Therefore, a novel approach for modifying the conventional deep drawing process to achieve a lubricant-free deep drawing process is introduced within this thesis. In order to decrease the amount of frictional force for a given friction coefficient, the integral of the contact pressure over the contact area has to be reduced. To achieve that, the flange area of the tool is macro-structured, which has only line contacts. To avoid the wrinkling, the geometrical moment of inertia of the sheet should be increased by the alternating bending mechanism of the material in the flange area through immersing the blankholder slightly into the drawing die.
40

Entwicklung und Umsetzung eines Moduls zur Inline-Faltenauswertung an Kartonziehteilen

Meyer, Martin 27 October 2015 (has links)
Die vorliegende Arbeit hat die Entwicklung und Validierung eines Inline-Faltenauswertungsmoduls zur Auswertung der Faltenverteilung an gezogenen Kartonformteilen im Prozess zum Ziel. Ein entsprechend konstruierter Versuchsaufbau ermöglicht die dafür notwendigen Bilddaten innerhalb des Ziehprozesses zu akquirieren und annähernd in Echtzeit auszuwerten. Durch den Ausgleich der graduellen Beleuchtung kann unter Anwendung eines zweidimensionalen Frequenzfilters eine Kontrastoptimierung zwischen Falten und Hintergrund erreicht werden, die die Auswertung der Daten begünstigt. Mittels Kreuzkorrelation mit einem Faltenmodell kann so die Position von Falten in Bildausschnitten lokalisiert werden. Dieser neuartige Ansatz ermittelt Falten nicht nur punktuell, sondern bezieht auch die Umgebung eines Pixels in die Analyse ein. Dadurch wird eine differenzierte Klassifizierung erreicht, die robust gegenüber Bildfehlern und Rauschen ist. Eine Korrekturfunktion berücksichtigt die durch die Abbildung der runden Zarge auf die Fokusebene resultierenden Positionsabweichungen und macht die Falten einer photogrammetrischen Messung zugänglich. So lassen sich mittlere Faltenabstände und deren Standardabweichungen ermitteln, die einem Vergleich mit Referenzmessmethoden standhalten. Mit Hilfe statistischer Tests kann gezeigt werden, dass vor allem aus hohen Faltenhalterkräften, und demzufolge feinverteilten Falten, größere Abweichungen zwischen dem Inline-Faltenauswertungsmodul und der Referenzmessmethode resultieren. Eine Fehlerdiskussion legt verschiedene Gründe für dieses Verhalten dar. Weiterführende Untersuchungen weisen die prinzipielle Eignung des Verfahrens für abweichende Geometrien und Materialien nach, zeigen jedoch auch Grenzen des eingesetzten Systems auf. Basierend auf den gewonnenen Erkenntnissen werden Verbesserungsansätze vorgeschlagen, die die Limitierungen der entwickelten Methode reduzieren können. / The present thesis includes the development and validation of a module for inline-examination of wrinkle-distribution on deep-drawn paperboard containers within the deep drawing process. A suitably constructed test-device allows to acquire the necessary images within the process and their approximately real-time evaluation. The usage of a two-dimensional frequency-filter accomplishes a contrast optimization between wrinkles and background by the compensation of a gradual illumination, which supports the evaluation of the wrinkles. Through the cross-correlation with a wrinkle-model, the position of wrinkles in image segments can be determined. This novel approach not only determines the wrinkles in a punctual way, but also it includes the environment of pixels. In this way a differentiating classification is possible, which is sturdy against image errors and noise. A correcting function considers the position errors caused by the mapping of the round frame of the deep-drawn paperboard container to the focal plane and makes the wrinkles available for a photogrammetric measurement. In this way averaged wrinkle-distances and their standard deviation can be determined that withstands the comparison with certain reference measuring methods. By statistical tests can be shown, that especially high blankholder forces and therefor small wrinkles result in higher differences between the inline examination-module and the reference measuring method. An error discussion explains various reasons for this behavior. Further tests prove the general suitability of the method for different geometries and materials, but also show limits of the applied system. Based on the gained knowledge, approaches for optimization are discussed that may improve the developed method.

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