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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.
41

3D-Simulation und Planung von Anlagen der Hütten- und Walzwerkstechnik

Oppermann, Ingo 11 May 2009 (has links) (PDF)
In der Präsentation werden typische Engineeringaufgaben präsentiert, die mit modernen IT-Werkzeugen erledigt werden. Es wird auf die Einführung und die Durchgängigkeit eines 3D-CAD-Systems eingegangen und gezeigt, wie mit diesem System Simulations- und Prozesskettenthemen in der Praxis bei der SMS Siemag AG behandelt werden. Ebenfalls anhand von Beispielen wird die Thematik der großen Baugruppen und der Anlagenplanung im 3D-Engineering dargestellt.
42

[en] NEW MODEL FOR THE SLAB STACK SHUFFLING PROBLEM INSIDE THE SLAB YARD OF A HRM / [pt] UMA NOVA PROPOSTA PARA O PROBLEMA DE REMANEJAMENTO DE PLACAS EM UM PÁTIO PARA ATENDIMENTO DE UMA LAMINAÇÃO

EDSON FELIPE AMADO FERNANDES 18 October 2018 (has links)
[pt] O presente trabalho desenvolve um novo modelo para um problema logístico de remanejamento de placas entre pilhas em um Pátio de Placas de uma Laminação, típico da indústria siderúrgica. Esta abordagem inclui uma nova característica que indica o destino das placas remanejadas. Uma nova metodologia de decisão altera sensivelmente o escopo do problema e traz um novo conceito: o balanço entre a escolha ótima das placas e o possível destino das placas remanejadas, ou seja, deve-se pesar a escolha da placa a ser laminada juntamente com a possibilidade de um bom remanejamento das placas que estão acima da mesma. Esse modelo não linear é linearizado por técnicas de linearização e resolvido através de programação linear inteira. Com isso, o estudo apresenta uma redução no tempo médio de manuseio de placas (TMM) de 5 minutos por placa laminada encontrado na literatura existente, para menos de 4 minutos. Finalmente o modelo proposto incentiva a construção de uma ferramenta de gestão que possa resolver o problema SSS em situações práticas do dia-a-dia através de redução de custo de operação como forma de viabilizar o investimento nesta ferramenta. / [en] This work develops a new model for a typical logistic problem in the steel industry known as slab stack shuffling problem inside a Slab Yard of a Rolling Mill. This new approach includes a new feature that indicates the destination stacks of shuffled slabs. A new decision methodology changes significantly thescope of the problem and introduces a new concept: the balance between optimal choice of the rolled slabs and possible destinations for shuffled slabs which means it must weigh the choice of the slab to be rolled engaged with a low cost shuffle operation for the slabs that are above the chosen slab. This nonlinear model is linearized through specific modeling techniques and solved by integer linear programming. Thus, this work shows a reduction in average handling time (TMM) from 5 minutes per rolled slab found in the literature, to less than 4 minutes. Finally, the proposed model encourages the construction of a management tool that can solve the SSS problem in practical daily situations through operating costs reduction as a payback of investment in this tool.
43

3D-Simulation und Planung von Anlagen der Hütten- und Walzwerkstechnik

Oppermann, Ingo 11 May 2009 (has links)
In der Präsentation werden typische Engineeringaufgaben präsentiert, die mit modernen IT-Werkzeugen erledigt werden. Es wird auf die Einführung und die Durchgängigkeit eines 3D-CAD-Systems eingegangen und gezeigt, wie mit diesem System Simulations- und Prozesskettenthemen in der Praxis bei der SMS Siemag AG behandelt werden. Ebenfalls anhand von Beispielen wird die Thematik der großen Baugruppen und der Anlagenplanung im 3D-Engineering dargestellt.
44

Effects of mill rotational speed on the batch grinding kinetics of a UG2 platinum ore

Makgoale, Dineo Mokganyetji 11 1900 (has links)
In this study, the effect of speed was investigated on the breakage rate of UG2 platinum ore in a batch mill of 5 dm3 and 175 mm internal diameter. One size fraction method was carried out to perform the experiment. Five mono-sized fractions in the range of 1.180 mm to 0.212 mm separated by √2 series interval were prepared. The fractions were milled at different grinding times (0.5, 2, 4, 15 and 30 min) and three fractions of mill critical speed were considered (20%, 30%, and 40%). The target of critical speed below 50% was due to the need of lower energy consumption in milling processes. The selection and breakage function parameters were determined and compared for fractions of critical speed. First the grinding kinetics of the ore was determined and it was found that the material breaks in non-first order manner. Thereafter, effective mean rate of breakage was determined. It was found that the rate of breakage increased with increase of mill speed and optimum speed was not reached in the range of chosen mill speed fractions. Again the rate of breakage was plotted as a function of particle size, the optimum size was 0.8 mm when milling at 30% critical speed. As for 20% and 30% optimum size was not reached. The selection function parameters estimated at 30% critical speed were 𝑎0 = 0.04 min−1 , 𝛼 = 1.36, 𝜇 = 0.9 mm, and Λ = 3. Breakage function parameters were determined and was noticed that the material UG2 platinum ore is non-normalised, i.e. Φ value was changing from 0.25 to 0.90 depending on feed size and mill speed. The parameters 𝛽 and 𝛾 were constant at 7.3 and 1.17 respectively. / College of Science, Engineering and Technology / M. Tech. (Chemical Engineering)
45

Development of Advanced Process Control for Controlling a Digital Twin as a Part of Virtual Commissioning

Uddin, Md Mehrab January 2021 (has links)
Over the last few decades, the complexity and variety of automation systems have increased dramatically. Commissioning has grown more and more critical for the entire industry. Conventional commissioning is time-consuming and expensive. It's always been a challenge in manufacturing to put new designs into production or implement new technologies, control codes, or tactics. In Virtual Commissioning (VC), control programs of the physical system's Digital Twin (DT) can be validated in Software-in-the-Loop (SIL) before the actual commissioning. The emergence of new VC tools and methods has become a tremendous advantage, bringing the values of shorter duration, flexibility, and lower risks to the commissioning process. In this thesis, advanced process control was developed using the software Matlab and Simulink in conjunction with the engineering tools S7-PLCSIM Advanced and STEP 7 TIA Portal to conduct VC. A VC approach with four key steps is taken to evaluate the possibility of validating advanced process control. The steps are modeling DT of a rolling mill, model-based control design, simulation model development in Simulink, communication between the simulation model and the PLC program using S-7 TIA Portal, and PLCSIM Advanced. Also, a simulated Human-Machine Interface was designed to operate and visualize the process. VC of the rolling mill process was verified and validated by Model-in-the-Loop (MIL) and SIL simulation. The simulation gives satisfactory results as both MIL and SIL show identical outputs of the process.

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