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Examination of a Damaged Slitting Knife using Scanning Electron Microscopy and Finite Element Simulations / Undersökning av en skadad skärskiva med svepelektronmikroskopi och finita element-simuleringarÖman, Love January 2021 (has links)
At voestalpine Precision Strip AB, the slitting process is used frequently. Slitting is a commonly applied manufacturing technique during sheet metal processing that aims to split large coils of sheet metal into narrower widths. The coiled sheets are uncoiled and transferred to a slitter, where they pass between rotating circular knives that produce long and straight cuts, splitting the wide sheet into desired widths. However, during operation, their slitting knives are occasionally damaged. This means that the knives must be replaced, which wastes both time and money. The goal of this project is therefore to examine the damage of a degraded slitting knife. A scanning electron microscope (SEM) is used to analyse the fracture surface and the microstructure of the knife. Further analysis of the knife is a Vickers hardness test to determine the knife’s hardness. Moreover, finite element (FE) simulations of the slitting process are performed in FE software Abaqus to understand the stresses that the knives are subject to during operation. The results show that the Mises stress reaches a maximum value of around 2250 MPa, which is approximately 75% of the materials yield stress in compression. The SEM images show clear signs of smooth cleavage zones in the fracture area, indicating that the knife has failed by a brittle fracture. Furthermore, the images reveal possible signs of fatigue. The hardness test proved that the knife is very hard with a hardness of 802,2 HV. Plenty of carbides were revealed by the microstructure test – mainly two types. MC vanadium carbides and M6C carbides mainly consisting of tungsten and molybdenum, which explains the hardness of the knife. To draw further conclusions on the damage of slitting knives in the future, there needs to be proper documentation of the slitting process. This involves taking note of the knife setup, the sheet material and its thickness, as well as the lifetime of the knives as failure occurs.
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The Development and Evaluation of the knife Finite ElementClark, Brett W. 01 August 1996 (has links) (PDF)
This thesis presents the development and evaluation of the knife finite element which is a degenerate case of a hexahedral element. The knife connectivity is an artifact of automatic all-hexahedral mesh generators. Currently, knives are propagated to the surface of the mesh for removal. However since this disturbs the surface mesh, other alternatives are needed. This thesis investigates the option of leaving the knife connectivity in the mesh and treating it as a valid finite element. The shape functions and stiffness matrix for the knife element are derived and evaluated using theoretical and practical evaluations. It is concluded that the knife finite element is a viable element and should be used in finite element analysis when the knife connectivity occurs. Using the knife element reduces the work involved with fixing the knife connectivity by propagation or other means and will produce acceptable results in most cases.
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Desenvolvimento de produtos inteligentes e suas implicações nos modelos de negócios : o caso SmartknivesHuber, Wagner January 2018 (has links)
O trabalho manual com facas nos frigoríficos geram altos índices de problemas ergonômicos, sendo um fator agravante o uso de facas com afiação deficitária que prejudica sua usabilidade. O objetivo deste trabalho é desenvolver uma inovação tecnológica aplicando o conceito de Internet das Coisas na criação de produtos inteligentes que permita aos frigoríficos atender requisitos informacionais de controle e registro de afiação das facas em uso e simultaneamente, propor alternativas de modelos de negócios que gerem vantagens econômicas para a empresa focal e seus clientes. Inicialmente é relatado o processo de desenvolvimento da inovação tecnológica batizada com o nome comercial SMARTKNIVES, a qual agrega à faca características de um produto inteligente que registra e compartilha dados e interage com outros sistemas. O valor adicional da informação gerada com os dados coletados permite para a empresa focal repensar seu formato de exploração comercial da inovação desenvolvida. São propostas três alternativas de modelo de negócio no conceito de Sistema Produto-Serviço após (i) revisão da literatura acerca de modelos de negócios com uso de Internet das Coisas e inovações tecnológicas, (ii) levantamento de dados sobre consumo e custo com facas tradicionais em dois frigoríficos brasileiros e (iii) comparação dos dados no modelo tradicional versus modelos propostos com o uso dos produtos SMARTKNIVES. Como resultado, foi possível atender os requisitos informacionais e normativos para o setor de frigoríficos brasileiros e observar a possibilidade de um aumento na vida útil dos produtos inteligentes. Tal aumento, aliado às novas possibilidades de monetização e modelos de negócios tipo PSS, permitem vantagens econômicas mais vantajosas que o cenário atual. / The manual work with knives in the slaughterhouses generates high rates of ergonomic problems, being an aggravating factor, the use of knives with poor edging that hinders its usability requiring greater physical effort during the labor activity. The objective of this paper is to develop a technological innovation that helps in the solution of the problems related to the sharpening and use of knives in the slaughterhouses and that still makes possible the proposition of innovations in business models that allow economic advantages for the manufacturer and their customers. This study in a first moment (Chapter 2) reports the process of developing a technological innovation for using knives in slaughterhouses trade named SMARTKNIVES that aggregates the knife features a smart product designed to integrate the day to day problems of customers, recording and sharing data as well as interacting naturally with other systems using Internet of things. The additional value of the information resulting from this development allows the focal company to rethink its format of commercial exploitation of the developed innovation. In the second stage of this study (chapter 3) the researcher proposes three new business model possibilities in the concept of Product-Service System (PSS) after; (i) review of the literature on business models with use of Internet of Things and technological innovations, (ii) data collection on consumption and cost in two Brazilian slaughterhouses using traditional knives and (iii) comparison with the results predicted by the focal company if the slaughterers used SMARTKNIVES products. The paper concludes that the proposed objectives were achieved because the technological innovation developed helps in the problem of knife sharpening in slaughterhouses and also allows the proposition of new business models economically more advantageous than the current one.
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The early medieval cutting edge of technology : an archaeometallurgical, technological and social study of the manufacture and use of Anglo-Saxon and Viking iron knives, and their contribution to the early medieval iron economyBlakelock, Eleanor Susan January 2012 (has links)
A review of archaeometallurgical studies carried out in the 1980s and 1990s of early medieval (c. AD410-1100) iron knives revealed several patterns, with clear differences in knife manufacturing techniques present in rural cemeteries and later urban settlements. The main aim of this research is to investigate these patterns and to gain an overall understanding of the early medieval iron industry. This study has increased the number of knives analysed from a wide spectrum of sites across England, Scotland and Ireland. Knives were selected for analysis based on X-radiographs and contextual details. Sections were removed for more detailed archaeometallurgical analysis. The analysis revealed a clear change through time, with a standardisation in manufacturing techniques in the 7th century and differences between the quality of urban and rural knives. Analysis of cemetery knives revealed that there was some correlation between the knife and the deceased. Comparison of knives from England, Dublin and Europe revealed that the Vikings had little direct impact on England's knife manufacturing industry, although there was a change in manufacturing methods in the 10th century towards the mass produced sandwich welded knife. This study also suggests that Irish blacksmiths in Dublin continued their 'native' blacksmithing techniques after the Vikings arrived. Using the data gathered a chaîne opértoire of the iron knife was re-constructed, this revealed that there was a specific order to the manufacture process and decisions were not only influenced by the cost of raw materials, the skill of the blacksmith and the consumer status, but also by cultural stimulus.
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A study on the Legal System of Controlling and Managing the National Police FirearmsPan, Hung-yen 20 July 2012 (has links)
One slight mistake or misuse of police firearms could infringe human¡¦s right; thus, when it comes to the controlling of police firearms, legal state will usually adhere to the principles of legal reservation strictly. Police officers need to deal with all sorts of various and strange situation in the society. However, the legal provisions can not regulate and list all kinds of police firearms, which will bring doubts to police officers if it is necessary for them to use firearms and news related to the misuse of firearms has been heard all the time. Since the controlling of police firearms is part of national administration, the purpose of using police firearms and protecting the right of human should be considered with the same aspect and extent under this democratic and legal state. Furthermore, stipulating a comprehensive act for controlling and managing the police firearms should not be limited with the interpretation of the law, but should be established with suitable rules for Taiwan to control and manage police firearms in terms of different aspects and comprehensive considerations.
Based on the 5 major frameworks of administration law, including the principles, organization, authority, remedy and supervision, this study aims at examining the legal system of national controlling of police firearms, in terms of legal and practice aspect, to clarify the problems that using police firearms might bring with researching by reference, historical analysis, comparative analysis and induction analysis. Through the study, a ¡§legal system of controlling and managing the national police firearms¡¨ should be set up comprehensively, so that the suggestions of adjusting the deficiency of current law can be made.
The current legal system of controlling and managing the national police firearms forms a basic shape; however, by this study, the deficiency of it has been found, such as the unspecific timing of firing, the scarcity of authority for assessing the liability of using firearms, the insufficiency of administrative authority system including administrative investigation,, the deficiency of national remedy and state compensation, vacancy of the mechanism of interior self-supervision and so on, which means that the 5 elements , including the principles, organization, authority, remedy and supervision, are left to be redressed. Fortunately, the problems may be corrected by the suggestions below. A, learn to enhance the firearms regulations from imitating how the on-duty police officers in Japan work. B, the National Police Agency of Ministry of the Interior can establish an authority to assess the liability of using firearms. C, make it a mandatory regulation to start administrative investigation before using firearms. D, state compensation should be complied with the original State Compensation Act. E, facilitate the mechanism of interior self-supervision by imitating the evaluation for universities. The government should examine the related problems of national police firearms as soon as possible, so that the reviewing and redressing can be conducted and the problems can be solved.
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Podnikatelský záměr rozvoje podniku / Business Plan of DevelopmentČapek, Jiří January 2010 (has links)
The goal of this master’s thesis is to suggest a business plan of development for e - shop expansion, that sells japanese kitchen knives. The theoretical part describes the forms of business, the method of composing a business plan and the requirements for establishing an e – shop. In the analytical part, the contemporary situation of the e – shop Jakuno is described and the situation of e-commerce in Czech Repulic as well. The conclusion of this thesis deals with the business plan itself and proposes its suggestions for improving the company efficiency.
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Typology of Projectile Points/Knives from Upper East TennesseeMcLachlan, Zoen 01 May 2021 (has links)
Projectile points/ knives (PPKs) are categorized by morphology, also called typology, and associated with cultural periods. A total of 64 PPKs in collections in the Archaeology Lab at East Tennessee State University were curated as untyped and without provenience. They were allegedly collected from ground surveys in Upper East Tennessee, but without archaeological context research had not been prioritized. The importance of such research lies in the fact that few publications exist on the region of Upper East Tennessee and many reference books on lithic typology portray PPKs through illustrations of the ideal morphology of each type. The challenge herein is that the lithic technologies excavated by archaeologists are typically used, worn, broken, or abandoned. A comparative collection of projectile points found in the field from the region of Upper East Tennessee is a valuable research resource. The 64 PPKs yielded 25 typologies that are, indeed, published from Upper East Tennessee and show variability from resharpening, wear, and other means. The comparative collection is curated at the East Tennessee State University Archaeology Lab at Valley Brook.
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What Makes the Cut: The Influence of Form on Clovis Knife Cutting EfficiencyMika, Anna 21 April 2022 (has links)
No description available.
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The Early Medieval Cutting Edge of Technology: An archaeometallurgical, technological and social study of the manufacture and use of Anglo-Saxon and Viking iron knives, and their contribution to the early medieval iron economy.Blakelock, Eleanor S. January 2012 (has links)
A review of archaeometallurgical studies carried out in the 1980s and 1990s of early medieval (c. AD410-1100) iron knives revealed several patterns, with clear differences in knife manufacturing techniques present in rural cemeteries and later urban settlements. The main aim of this research is to investigate these patterns and to gain an overall understanding of the early medieval iron industry. This study has increased the number of knives analysed from a wide spectrum of sites across England, Scotland and Ireland. Knives were selected for analysis based on x-radiographs and contextual details. Sections were removed for more detailed archaeometallurgical analysis.
The analysis revealed a clear change through time, with a standardisation in manufacturing techniques in the 7th century and differences between the quality of urban and rural knives. Analysis of cemetery knives revealed that there was some correlation between the knife and the deceased. Comparison of knives from England, Dublin and Europe revealed that the Vikings had little direct impact on England¿s knife manufacturing industry, although there was a change in manufacturing methods in the 10th century towards the mass produced sandwich welded knife. This study also suggests that Irish blacksmiths in Dublin continued their ¿native¿ blacksmithing techniques after the Vikings arrived. Using the data gathered a chaîne opértoire of the iron knife was re-constructed, this revealed that there was a specific order to the manufacture process and decisions were not only influenced by the cost of raw materials, the skill of the blacksmith and the consumer status, but also by cultural stimulus.
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Functional Analysis of Polished-edge Discoidal Knives of the British IslesMetzger, Melissa A. January 2018 (has links)
Polished-edge discoidal knives are part of the lithic material culture from the
British Isles with an approximate Late Neolithic date. These artefacts are
manufactured in three basic shapes: circular to D-shaped, triangular, and broad
leaf to lozenge (Clark 1929).
The aim of this project was to explore the function of polished-edge discoidal
knives. To achieve this aim, the following objectives were completed: Objective
1: Develop a broad understanding of the literature surrounding polished-edge
discoidal knives; Objective 2: Develop a database containing all the available
information regarding the known knives for study in this project and as a tool to
help further research and select archaeological samples for study based on type,
condition, find location, and current location; Objective 3: Understand how these
tools were used; and Objective 4: Review all data and produce a narrative about
polished-edge discoidal knives’ function in Late British Neolithic Society.
This project has revealed that these knives were possibility used for activities
involving birch bark, clay, or other wood types. This research has also produced
a database of knives, a modern distribution map, a revised typology, an
archaeological date and possible contexts, and an object itinerary.
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