Motorkomponentvervaardigers staar wêreldwye mededingende uitdagings in die gesig, en die paradigma het verskuif van produkprys as die bepalende faktor van mededingendheid na die kwaliteit van die produk. 'n Vervaardiger van motoronderdele het gesukkel om die uitvloei van gebreke te bestuur, en die toevoeging van inspekteurs as kwaliteithekke na die agterbufferproduksielyn het ernstige koste-implikasies gehad. Hierdie studie het ten doel gehad om die aantal defekte te verminder deur 'n strategiese roete te implementeer om ingeboude kwaliteit te implementeer. Kwaliteitgereedskap is gebruik, en die studie se resultate het aansienlike vermindering van mannekrag, verbeterde kwaliteitvermoë en verminderde skroottariewe en herbewerkings ingesluit.

Automotive component manufacturers face global competitive challenges, and the paradigm has shifted from product price as the determining factor of competitiveness to the quality of the product. An automotive component manufacturer was struggling to manage the outflow of defects, and adding inspectors as quality gates to the rear-step bumper production line had severe cost implications. This study aimed to reduce the number of defects by deploying a strategic path of implementing built-in quality. Quality tools were used, and the study's results included significant manpower reduction, improved quality capability, and reduced scrap rates and reworks.

ABSTRACT Natural fiber reinforced composite materials are used to make the best outcome materials due to their ease of availability, ability to be recycled, and environmental friendliness. The items made from this substance can help both urban and rural locations. Borassus flabellifer L fruits, leaves, and stems are commercially used, although some are discarded as scrap. This byproduct of Borassus-Flabellifer L can be utilized as a fiber source and as the principal component of natural fiber polymer composites with reinforcement. Apart from conventional methods of water retting or dew retting and mechanical decortication to extract the fiber, in this study new novel methods of extraction take place. An examination is conducted on Borassus Flabellifer fruit fibers that have been treated with alkaline and peroxide solvents. The purpose of this inquiry is to assess the possibility of using these fibers as reinforcement in composites. The presence of cellulose, hemicellulose, and lignin can be determined by conducting a chemical analysis. The effect of various chemical treatments on morphological attributes is assessed using SEM and UTM techniques. The X-ray diffraction examination reveals that the crystallinity of the fibers is altered by various chemical treatments, as observed in both the untreated fibers and those subjected to chemical treatment (i.e.,) Alkali (NaOH), Hydrogen peroxide (H2O2) and NaOH + H2O2. The effectiveness of Borassus Flabellifer fruit fibers as a component of natural polymer composites is examined. availability recycled friendliness locations fruits leaves scrap BorassusFlabellifer place solvents cellulose hemicellulose analysis techniques Xray X ray i.e., ie i e (i.e., NaOH, , (NaOH) H2O2 HO H O (H2O2 examined i.e. (i.e. (NaOH H2O (H2O i.e (i.e

Abstract The purpose of this study was to evaluate the cleanliness of Interstitial Free (IF) steels produced in a Ruhrstahl Heraeus (RH) vacuum degasser by determining the level of Al2O3 and Al-Ti-O inclusion types generated in three different process conditions: i) steel processed without thermal intervention; ii) steel processed with chemical heating and iii) steel processed with cooling by the scrap addition. The inclusion formation and remotion during these processes were analyzed. The influence of homogenization time was also studied. The content of inclusions was measured by a Scanning Electron Microscope (SEM) with an automated counting system denoted as Automated Steel Cleanliness Analysis Tool (ASCAT). This method can provide the size and composition of non-metallic compounds. The results have shown that the Ruhrstahl Heraeus (RH) process can improve the remotion efficiency of the inclusions, such as those larger than 2.5 mm, which is due to the molten steel circulating in RH vessel. For some inclusion types, higher concentrations were detected, but their size was smaller. For a heat where it was necessary to apply chemical heating using Al addition and O injection, there was detected a higher concentration of inclusions when compared with that cooled by scrap addition. In cooling heats, there is a strong generation of small and thin inclusions (<1.0 mm) that are very difficult to be removed from liquid steel. The size of the Al2O3(s) type is around eight times larger than Al-Ti type inclusions. IF (IF (RH AlO Al2O AlTiO Ti conditions i intervention ii iii analyzed studied SEM (SEM ASCAT. ASCAT . (ASCAT) nonmetallic non metallic compounds 25 2 5 2. mm vessel smaller injection heats <1.0 10 1 0 (<1. Al2O3s AlOs s Al2O3(s AlTi (ASCAT <1. (<1 <1 (< < (

Abstract Large quantities of scrap tires are produced by the automobile industry each year, which causes disposal challenges and impacts the environment. However, scrap tires exhibit various properties, including tensile strength, abrasion resistance, durability, thermal conductivity, elasticity, and more. Due to their versatile characteristics, these scrap tires can be utilized as construction materials for various civil engineering works to reduce their negative environmental effects and conserve natural resources. This study aims to understand the shear strength behaviours exhibited by geocell-reinforced mixtures of rubber and sand through the unconsolidated undrained triaxial test. Various parameters, including rubber sizes (425 μm to 12 mm), rubber contents (10% to 40% by volume), confining pressures (50 to 300 kPa), and geocell heights (0.2H to 0.8H, where H is the height of triaxial sample), were systematically examined to understand their impact on shear strength characteristics. The experimental findings reveal that deviatoric stress is enhanced with increasing confining pressure and rubber sizes. The maximum benefits of the rubber-sand mixture were observed at 30% rubber content. Geocell-reinforced rubber sand mixture has a higher shear strength with respect to the unreinforced mixture. Furthermore, the energy absorption capacity of the geocell-reinforced rubber sand mixtures was much better as compared to either the clean sand or rubber-sand mixture. The findings of this research demonstrate that geocell-reinforced rubber sand mixtures are suitable for various geotechnical engineering works. year environment However properties resistance durability conductivity elasticity more characteristics resources geocellreinforced reinforced test parameters 425 (42 1 mm, mm , mm) 10% 10 (10 40 volume, volume volume) 50 (5 30 kPa, kPa kPa) 0.2H 02H 0 2H 08H 8H 0.8H sample, sample sample) rubbersand content Geocellreinforced Geocell Furthermore 42 (4 (1 4 5 ( 3

Abstract In dealing with the radical politicization of psychoanalysis from a geopolitical standpoint, this essay argues that psychoanalysis has to be capable to rethink and reembody itself with every contingent and immanent dislocations of its transcendental horizons. Through a reading of Slavoj Žižek and Alain Badiou on Mao Tse-Tung, we can think about the notion of dislocation and localization of the Idea. We will argue that this has historically happened in psychoanalysis in the transition from Freud to Lacan; however, the issue is that this dislocation has undergone a retroactivity of necessity which makes a vanishing mediator out of the contingent scrap of reality that it initially relied on-and this forms the quilting point of the contemporary Lacanian ideology. Through Gabriel Tupinambá›s The Desire of Psychoanalysis, we will inspect the notion of generic psychoanalysis. We will insist that while generic psychoanalysis is crucial for the refiguring of psychoanalytic politics in a dislocative matter, we need to take this outlook to the end onto a psychoanalysis that is willing to impurify itself through localization as this is the only psychoanalysis worthy of the name.

Resumen En dialogo con la politización radical del psicoanálisis desde un punto de vista geopolítico, este ensayo argumenta que el psicoanálisis tiene que ser capaz de repensarse y re-corporarse a sí mismo con cada dislocación contingente e inmanente de sus horizontes trascendentales. A través de una lectura de Slavoj Žižek y Alain Badiou sobre Mao Tse-Tung, podemos pensar la noción de dislocación y localización de la Idea. Argumentaremos que esto ha sucedido históricamente en el psicoanálisis en la transición de Freud a Lacan; sin embargo, la cuestión es que esta dislocación ha sufrido una retroactividad de la necesidad que hace un mediador que se desvanece de la chatarra contingente de la realidad en la que inicialmente se apoyó, y esto forma el punto de acolchado de la ideología lacaniana contemporánea. A través de The Desire of Psychoanalysis de Gabriel Tupinamba, inspeccionaremos la noción de psicoanálisis genérico. Insistiremos en que, si bien el psicoanálisis genérico es crucial para la refiguración de la política psicoanalítica en un asunto dislocador, necesitamos llevar esta perspectiva hasta el final en un psicoanálisis que esté dispuesto a impurificarse a sí mismo a través de la localización, ya que éste es el único psicoanálisis digno de ese nombre.

Abstract. - A hydraulic clamping device was developed for the broaching process of Brackets used in automotive braking systems, which allows reducing the variation of the cutting process by improving the clamping system and thereby limiting the deformation of the piece after having been processed. With this concept of device, it is possible to improve the conditions of the production process such as: cutting speed, cycle time reduction, operation performance, scrap cost reduction, and downtime reduction due to process over-adjustment and change over. Additionally, the development of a part detection system was made that allows capturing when a part is not correctly placed in the device before starting the cutting cycle, with this it is possible to detect failures in the process that represent a risk to the operation. During the design stage, a simulation of the machining process was carried out in extreme conditions and ideal conditions to measure the deformation of the part and with this obtain the appropriate cutting parameters for the implementation of the clamping device. For the validation of the model, a Cpk and Ppk process ability study was carried out (according to customer requirements) to assess that the new process is efficient and is under control.

Resumen. - Se desarrollo un dispositivo de sujeción hidráulica para el proceso de brochado de Brackets usados en los sistemas de frenado de automóviles, que permite reducir la variación del proceso de corte al mejorar el sistema de sujeción y con ello limitar la deformación de la pieza luego de haber sido procesada. Con este concepto de dispositivo es posible mejorar las condiciones del proceso de producción, como lo son: velocidad de corte, reducción de tiempo ciclo, rendimiento de la operación, reducción de costo de scrap, y reducción de tiempo muerto por sobre ajuste de proceso y cambio de modelo. Adicional, se hizo el desarrollo de un sistema de detección de pieza presente que permite captar cuando una pieza no es colocada correctamente en el dispositivo antes de iniciar el ciclo de corte, con esto es posible detectar fallas en el proceso que representen un riesgo para la operación. Durante la etapa de diseño se realizó una simulación del proceso de maquinado en condiciones extremas y condiciones ideales para medir la deformación de la pieza y con esto obtener los parámetros adecuados de corte para la puesta en marcha del dispositivo de sujeción. Para la validación del modelo, se realizó un estudio de habilidad de proceso Cpk y Ppk (acorde a los requerimientos de cliente) para evaluar que el nuevo proceso es eficiente y se encuentra bajo control.

Abstract Scraped or end-of-life WC-Co bonded makes it an attractive resource. The conventional technologies to recover these metals entail energy-intensive pre-treatment steps, followed by their dissolution in a high volume of concentrated acids/alkali reagents. Recently, much attention has been given to the development of energy-efficient and environmentally friendly routes based on WC-Co direct electrochemical dissolution as anodes. However, the metals have a retarded dissolution, in NaOH alkali media, due to the formation of passive oxide layers, in the acidic electrolytes, and of hydroxides, on the anodic surface. The present study investigated WC and Co dissolution fundamentals in aqueous NH3, in order to develop a greener process, by the suitable addition of (NH4)2CO3, (NH4)2SO4 and NH4Cl Preliminary PDP studies revealed the necessary concentration of NH3 and additives, and their effect on the metals passivation tendency, for obtaining the best anodic dissolution parameters. The electrodissolution experiments in a specially designed cell achieved the maximum values, by adjusting those parameters. The highest dissolution of W and Co occurred under optimum conditions (10 V, 150 g/L NH3 and 15% w/v NH4Cl). Co was deposited at the cathode, while H8N2O4W remained in the electrolyte and was recovered as H2WO4 or YTO. Topographical analysis of the polarized surface by AFM has confirmed the pitting corrosion mechanism responsible for W and Co dissolution. A process flow chart for the newly developed single-step direct recycling methods of WC scraps has also been proposed. This process has produced pure saleable WO3 powder and Co.

Decolonisation has recently captured the attention of those who inhabit South African universities, mainly sparked by student protests of 2015 and 2016. In this article writing is used as a mode of inquiry to explore what it means to decolonise the university in a contemporary world that is confronted with crises of all kinds; political, economic, environmental, health, education, and so forth. A third world university is pitted against a first world university (the neoliberal university that accumulates) and a second world university (the university that critiques), not as a new utopian idea but as a university that scavenges on the scrap material of the first and second world universities to retool them for decolonial purposes. In doing so the article changes the angle of vision on decolonising the university in South Africa and elsewhere. The author thinks with la paperson's ideas including hir notion of scyborg, which refers to people who use their agency to retool material of the first and second world universities to garner decolonial desires. A third possibility for the university jettisons the idea of a totalizing, utopian, decolonised university. What is possible is that the university can operate like a decolonised university, without being disengaged from the first and second world universities, signifying new ways of thinking/doing research, teaching, learning and community engagement.

The following essay is part of a body of work titled Signal to Noise: sound and fury in (post)apartheid South Africa. These are a collection of creative non-fiction essays set against the backdrop of my involvement with a small, independent mobile recording studio based in Johannesburg between 1983 and 1997. The metaphor of a drowning signal, pushing through and making itself heard above the noise, resonates throughout the collection. The complexities of the political versus artistic nature of what we were involved with provide a setting for an anecdotal approach to what is part history, part biography, part memoir and part theoretical sonic exploration. The following essay falls into this approach and is constructed from memories enhanced by diaries, scrap-books, shards of notes, lyrics, photos and conversations. These have been employed in reconstructing a narrative arc that covers the recording of the first album made by the band Sankomota, who were banned from entry into South Africa and were based in Maseru, mostly playing to audiences at one of the leading hotels. Sankomota, then called Uhuru, experienced extraordinary, almost metaphysical, peaks and troughs throughout their nearly thirty-year existence hence the hauntological device in the title. The record was also the first made in our fledgling mobile studio using newly affordable equipment that kickstarted many such do-it-yourself projects worldwide. This was the first in a steady stream of technologies that would eventually break the hegemony of mainstream record companies. In apartheid South Africa, this was hugely significant, as being able to sideline the censorship of state-owned media enterprises meant immense freedom in the kind of projects one came to consider. Savage incidents of force and brutality were still common then, and our small venture has to be seen in the context of broader unrest and suffering. Frank Leepa was an uncompromising survivor. His words and melodies still move and inspire a younger generation.

Recycled crumb rubber can be sustainable used in mortar both to mitigate nature aggregate consumption, reducing environmental pollution, as well, to improve the acoustic and thermal performance of buildings, without damaging its mechanical properties. This paper explores workability, microstructure, mechanical, thermal and acoustic properties considering increasing contents of crumb rubber (0%, 5%, 10%, 15% and 20% replacement, by volume, of fine aggregate). Mortar characterization tests were carried out in the fresh and hardened state. It has been found that replacing the aggregate with scrap tyre rubber reduced the compressive strength on average 12% and 67% and for tensile strength 35% and 53%, for the contents of 10% and 20% respectively, compared to the reference. Furthermore, it was found that the reductions in thermal conductivity reached 16% and 29% and an increase in acoustic attenuation on average 12% and 13%. Moreover, scanning electron microscopy images were analyzed, justifying the mechanical results obtained. Although the experimental results indicated that the workability and mechanical strengths decreased with the increase of rubber replacement rate, the studied mixtures met the standard specifications, and thus suitable for walls and ceilings coating applications, improve the acoustic and thermal performance of buildings and as a sustainable material. consumption pollution well microstructure 0%, 0 (0% 5 5% 10 15 20 volume aggregate. . aggregate) state 12 67 35 53 53% respectively reference Furthermore 16 29 13 13% Moreover analyzed obtained rate specifications applications material 0% (0 1 2 6 3 (

RESUMO Zamac é uma liga metálica composta de zinco, alumínio, magnésio e cobre. Suas propriedades de processamento, como baixo ponto de fusão e alta fluidez a quente faz com que a indústria reprocesse o refugo da produção de zamac sem enviá-lo a uma usina para refino, podendo ocasionar diferenças de composição química na liga original e consequentemente nas suas propriedades mecânicas e microestruturais. Este trabalho visa avaliar as variações oriundas do reprocessamento de zamac 5 na forma de sucata contendo eletrodeposição de cobre alcalino quanto à microestrutura e às propriedades mecânicas. As amostras reprocessadas foram comparadas com amostras de zamac 5 como recebidas e analisadas por meio de ensaios de dureza, resistência à compressão, microestrutura por microscopia eletrônica de varredura e de composição química por EDS. Os resultados de ensaio de resistência à compressão e composição química mostram que houve a formação de uma liga nova, com aumento da concentração de aproximadamente 4% de cobre, muito semelhante à liga ternária Zn-15Al-4Cu. Embora essa liga nova tenha apresentado resultados de dureza alta e resistência à compressão relativamente baixa, preliminarmente, pode-se dizer que é adequada para fabricação de peças que não recebem esforços compressivos significativos, como enfeites para roupas, bolsas, calçados e acessórios. zinco alumínio processamento enviálo enviá lo refino microestruturais EDS 4 Zn15Al4Cu. Zn15Al4Cu ZnAlCu Zn 15Al 4Cu. 4Cu Al Cu Zn-15Al-4Cu baixa preliminarmente podese pode se significativos roupas bolsas acessórios

ABSTRACT Zamac is a metallic alloy composed of zinc, aluminum, magnesium and copper. Its processing properties, such as low melting point and high hot fluidity, make the industry reprocess the waste from zamac production without sending it to a plant for refining, which can cause differences in chemical composition in the original alloy and consequently in its mechanical and microstructural properties. This work aims to evaluate the variations arising from the reprocessing of zamac 5 in the form of scrap containing alkaline copper electrodeposition in terms of microstructure and mechanical properties. The reprocessed samples were compared with zamac 5 samples as received and analyzed using hardness, compressive strength, microstructure tests using scanning electron microscopy and chemical composition tests using EDS. The results of the compressive strength and chemical composition tests show that a new alloy was formed, with an increase in copper concentration of approximately 4%, very similar to the ternary alloy Zn-15Al-4Cu. Although this new alloy has shown results of high hardness and relatively low compressive strength, preliminarily, it can be said that it is suitable for manufacturing parts that do not receive significant compressive stresses, such as decorations for clothes, bags, shoes and accessories. zinc aluminum properties fluidity refining EDS formed 4 4% Zn15Al4Cu. Zn15Al4Cu ZnAlCu Zn 15Al 4Cu. 4Cu Al Cu Zn-15Al-4Cu preliminarily stresses clothes bags accessories

Resumo A indústria da construção civil é uma das maiores consumidoras de recursos naturais. Por se encontrar em ambiente marinho, por sua magnitude e por sua produção elevada de resíduos da construção civil, obras portuárias possuem potencial poluidor, e a literatura técnico-científica sobre o assunto é incipiente. O objetivo desta pesquisa foi analisar índices de geração de resíduos sólidos durante a construção de um porto. Realizou-se o acompanhamento por 20 meses da gestão de resíduos sólidos ocorrentes na obra do Porto Dom Pedro II, em Paranaguá (PR). Por meio da avaliação aplicável à gestão de resíduos e de medições em campo, o processo de gestão dos resíduos sólidos foi caracterizado quanto aos agentes envolvidos, à origem, ao tipo, à quantidade, à taxa de geração, ao reúso e à destinação final. Foi avaliada a eficiência do processo de gerenciamento, e obtiveram-se índices de geração per capita e por área e de aproveitamento de resíduos. A composição, em massa, dos resíduos sólidos gerados na obra foi: sucata metálica (48%), sucata de madeira (29%), resíduo orgânico (10%), resíduo reciclável (8%) e resíduos perigosos (4%). Os indicadores de geração de resíduos mensais per capita foram calculados em: resíduos orgânicos (12,75 kg), ambulatoriais (8,14g), resíduos perigosos (5,33kg), copos plásticos (70,5 unidades) e equipamentos de proteção individual (3,89 unidades). Quanto à área construída, a geração média mensal de resíduos foi calculada em 0,35 kg/m2 (resíduos perigosos), 3,51 kg/m2 (madeira), 7,5 kg/m2 (sucata metálica) e 0,97 kg/m2 (orgânicos). Além do mapeamento de oportunidades de melhoria, os índices de geração e de aproveitamento calculados podem ser utilizados na gestão de resíduos da construção civil de obras semelhantes.

Abstract The construction industry is one of the largest consumers of natural resources. As it is in a marine environment and due to its magnitude and the high production of Construction and Demolition Waste (CDW), port works have a polluting potential and the technical-scientific literature on the subject is incipient. The objective of this research was to critically evaluate waste generation indexes of CDW during the construction of a port. The monitoring of the solid waste management from the Dom Pedro II port site in Paranaguá, Paraná, was carried out for 20 months. Through the assessment applicable to waste management and field measurements, the solid waste management process was characterized in terms of the agents involved, origin, type, quantity, generation rate, reuse, and destination. The efficiency of the management process was evaluated, and waste generation and utilization of Key Performance Indicators, per capita and per area, were obtained. The composition, in mass, of the solid waste generated in the work was: metallic scrap (48%), wood scrap (29%), organic waste (10%), recyclable waste (8%), and hazardous waste (4%). Per capita monthly waste generation indicators were calculated as: organic waste (12.75 kg), outpatient waste (8.14g), hazardous waste (5.33kg), plastic cups (70.5 units), and PPE (3 .89 units). As for the built-up area, the average monthly generation of waste was calculated at 0.35 kg/m² (hazardous waste), 3.51 kg/m² (wood), 7.5 kg/m² (metallic scrap), and 0.97 kg /m² (organic). In addition to mapping opportunities for improvement, the calculated generation and utilization indexes can be used in the CDW management of similar works.

Abstract This paper contains the design of a man-machine system model for the machine tools based on a serial-parallel configuration and their component-subsystem relationships. Causal Analyses and a classification system using the Cluster Analysis were used to analyze the non-conforming pieces that occurred in 3 machine shops from the metal mechanical sector, and to design the man-machine system model. The man-machine system model proposes to provide adequate conditions to apply some statistical reliability assessment models with a serial-parallel systems approach, and on the assumptions of the constant and additive failure rate of the Exponential and Weibull functions respectively. As an input of the first statistical model, the times to failure from non-conforming pieces and goodness of fit test have been used to assess the reliability of component-subsystem relationships. For the second statistical model the reliabilities from component-subsystem relationships were used to assess the reliability of subsystems as serial systems configuration. Inputs for the third statistical model have used reliabilities from subsystems to assess the reliability of the man-machine system as a parallel system configuration. The man-machine system and statistical models were implemented and validated in a company from the metal-mechanical sector with a low-volume and high-mix production rate whose operations were carried out by both conventional and CNC machines. Based on the man-machine system analysis was possible to know the formal structure of machine tools that generate non-conforming pieces in the scrap area as well as to identify the subcauses of failure that affect the system (components). Components identified were: maintenance/set up, institutional conditions/attitude, admission profile, information/communication, calibration, and supplier. Also, the most common places where failures occurred (subsystems) were identified. Subsystems identified were: machine, tool, process/operation, measurement/instrumentation, programming/design, and material. Through the selected statistical models was possible to get reliability indices for each component-subsystem relationship, for each subsystem as well as for the whole man-machine system, identifying areas for improvement. The company where the methodology was implemented and validated presented a high volume of scrap in the machine tool and it was possible to identify that the subsystem: process/operation and the components: maintenance/set up and institutional conditions/attitude had the lowest reliability, and they were considered as opportunities areas for improvement. For 7 hours the man-machine reliability is 0.1409 (the probability to find a product without failures for which it must be scrapped is 14.09%). In the machine shop, the issues that caused these low levels of reliability are attributed to the insufficient preventive and predictive maintenance program. Improvement actions are considered in another research. This kind of research investigates a little-studied problem, as it is about the reliability of the man-machine system in machining tools and investigates from an innovative perspective and preparing the ground for new studies in the metal mechanical sector.

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Resumo Este trabalho contém o sistema homem-máquina da área de usinagem, baseado na configuração série-paralelo e nas relações componente-subsistema. A análise de causa e um sistema de classificação através da Análise de Cluster foram utilizados para analisar as peças não conformes que ocorreram em 3 oficinas de usinagem do setor metalmecânico e projetar o modelo do sistema homem-máquina. O objetivo do modelo de sistema homem-máquina é fornecer as condições adequadas para aplicar alguns modelos estatísticos para avaliar a confiabilidade, com a abordagem dos sistemas série-paralelo e sob as hipóteses de uma taxa de falhas constante e aditiva das distribuições exponenciais. e Weibull respectivamente. Como entrada para o primeiro modelo estatístico, tempos para falhas de peças não conformes e testes de ajuste foram usados para avaliar a confiabilidade das relações componente-subsistema. Para o segundo modelo estatístico, as confiabilidades das relações componente-subsistema foram utilizadas para avaliar a confiabilidade dos subsistemas, com a configuração dos sistemas em série. As entradas do terceiro modelo estatístico, as confiabilidades dos subsistemas, foram utilizadas para avaliar a confiabilidade do sistema homem-máquina, com a configuração de um sistema paralelo. O sistema homem-máquina e os modelos estatísticos foram implementados e validados em uma empresa do setor metal-mecânico de baixo volume e alta taxa de produção de mix, cujas operações são realizadas por máquinas convencionais e de Controle Numérico (CNC). Com o sistema homem-máquina foi possível conhecer a estrutura formal das áreas de usinagem a partir das peças não conformes da área de sucata e identificar as subcausas de falha que afetam o sistema (componentes). Os componentes identificados foram: manutenção/configuração, condições/atitude institucionais, perfil de entrada, informação/comunicação, calibração e fornecedor. Também foram identificados os locais mais comuns de ocorrência de falhas (subsistemas). Os subsistemas identificados foram: máquina, ferramenta, processo/operação, medição/instrumentação, programação/projeto e material. Através dos modelos estatísticos foi possível obter os índices de confiabilidade para cada relação componente-subsistema, para cada subsistema, bem como para o sistema homem-máquina, identificando assim áreas de melhoria. A empresa onde a metodologia foi implantada e validada apresentou alto índice de refugo na área de usinagem e foi possível identificar que o subsistema processo/operação e os componentes manutenção/configuração e condições institucionais/atitude tiveram a menor confiabilidade e foram considerados como áreas de oportunidade de melhoria. Durante 7 horas a confiabilidade homem-máquina é de 0,1409 (a probabilidade de encontrar um produto sem defeitos pelo qual deve ser descartado é de 14,09%). Na oficina mecânica, os problemas que causaram esses baixos níveis de confiabilidade são atribuídos a um programa de manutenção preventiva e preditivo insuficiente. Ações de melhoria são consideradas em outra investigação. Esse tipo de pesquisa estuda um problema pouco estudado, como a confiabilidade do sistema homem-máquina nas áreas de usinagem, e investiga sob uma perspectiva inovadora, além de preparar o campo para novos estudos no setor metalmecânico.

Resumo Os compostos nitroaromáticos possuem importante relevância econômica e industrial fazendo parte de diversos insumos como corantes, tintas, agroquímicos e explosivos. Na fabricação do explosivo 2,4,6 trinitrotoluneo (TNT), há a formação de águas residuárias contaminadas de difícil tratamento por conter, dentre outros compostos, elevadas concentrações de 2,4 e 2,6-trinitrotolueno (DNT). Neste trabalho foi estudada a aplicação de Processos oxidativos avançados do tipo O3/UV em integração sequencial com material catalítico a base de escória de ferro metálico (SZVI) e matriz mineral, para o tratamento de um efluente industrial oriundo da indústria de explosivos contaminado com compostos nitroaromáticos. Foram estudados dois tipos de composição de matriz mineral, caulinita (Kau) e pedra pomes em pó (Pum), tendo sido observado, nas condições de melhor eficiência (O3/UV-SZVI/Kau), 100% de remoção tanto dos compostos dinitroaomáticos quanto de ozônio residual. Por outro lado, a foto-ozonização isoladamente, foi capaz de remover apenas parcialmente estes componentes, tendo sido observados 38% de remoção de DNT e 3,2 mg/L de O3 residual, comprovando a importância da integração com a matriz catalítica para um tratamento mais efetivo do efluente em estudo.

Abstract Nitroaromatic compounds have significant economic and industrial relevance in various inputs such as dyes, inks, agrochemicals, and explosives. In the manufacture of the explosive 2,4,6 trinitrotoluene (TNT), there is the formation of contaminated wastewater that is difficult to treat because it contains, among other compounds, high concentrations of 2,4 and 2,6-trinitrotoluene (DNT). In this work, the application of advanced oxidation processes of the O3/UV type was studied in sequential integration with catalytic material based on metallic iron slag (SZVI) and mineral matrix to treat an industrial effluent from the explosives industry contaminated with compounds nitroaromatics. Two types of mineral matrix composition were studied, kaolinite (Kau) and pumice powder (Pum), having been observed in the conditions of best efficiency (O3/UV-SZVI/Kau) 100% removal of both nitroaromatic compounds and residual ozone. On the other hand, photo-ozonation alone could only partially remove these components, with 38% DNT removal and 3.2 mg/L residual O3 observed, proving the importance of integration with the catalytic matrix for more effective treatment of the studied effluent.

RESUMO Empresas fornecedoras de Zamac reciclam sucatas de peças técnicas provenientes do processo produtivo de zamac injetado sob pressão e revestido por eletrodeposição. No entanto, somente 35% da sucata enviada para beneficiamento é reciclada e retorna para o processo produtivo como matéria-prima. Levando em consideração que a matéria-prima é um dos principais custos das empresas, o reaproveitamento de sucata representa uma oportunidade de economia para o processo fabril. Com isso, o objetivo desse trabalho foi verificar a viabilidade de fundição de sucatas de peças técnicas como matéria-prima para a fabricação de peças para o mercado da moda. A sucata foi analisada quanto à composição química, microestrutura e características térmicas. A sucata foi fundida sob pressão para produção de componentes para calçados e acessórios (elementos estéticos como fivelas e enfeites). Para comparação, enfeites e fivelas foram obtidos com matéria-prima virgem. Os enfeites e fivelas foram analisados quanto à microestrutura, resistência à corrosão e propriedades mecânicas. As amostras fundidas com uso de sucata responderam de forma satisfatória a todos os ensaios e, em alguns casos, de maneira superior às peças de controle, que foram fundidas com matéria-prima virgem. Assim, constatou-se que a sucata oriunda de peças técnicas pode ser usada como matéria-prima para produção de peças e acessórios para o setor de moda e, neste contexto, representa uma possibilidade de redução de custo de fabricação.

ABSTRACT Zamak supplier companies recycle scraps of technical parts from the production process of zamak injected under pressure and coated with electrodeposition. However, only 35% of the scrap sent for processing is recycled and returns to the production process as raw material. Taking into account that raw material is one of the main costs of companies, the reuse of scrap represents an opportunity to save the manufacturing process. With that, the objective of this work was to verify the viability of casting scraps of technical parts as raw material for the manufacture of parts for the fashion market. The scrap was analyzed for chemical composition, microstructure and thermal characteristics. The scrap was melted under pressure to produce components for shoes and accessories (aesthetic elements such as buckles and ornaments). For comparison, ornaments and buckles were obtained from virgin raw material. The ornaments and buckles were analyzed for microstructure, corrosion resistance and mechanical properties. Samples cast using scrap responded satisfactorily to all tests and, in some cases, better than control parts, which were cast with virgin raw material. Thus, it was found that scrap from technical parts can be used as raw material for the production of parts and accessories for the fashion sector and, in this context, it represents a possibility of reducing manufacturing costs.