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Performance measurements of rail curve lubricantsWilson, Lance Jon January 2006 (has links)
Wear of railroad rolling stock and rails costs millions of dollars annually in all rail systems throughout the world. The rail industry has attempted to address flange wear using rail curve lubricants and presently use a variety of lubricants and lubricant applicators. The choice of lubricant and applicator is currently based on considerations that do not address the wear problem directly. This research quantified rail curve lubricant performance through laboratory simulation. The effects of lubricants in the wheel/rail contact were investigated. Rail curve lubricant performance was measured with a laboratory rail/wheel simulator for the purpose of optimising the choice of lubricant. New methods for measurement of rail curve lubricant performance have been presented. These performance measurements are total absorbed energy, the energy absorbed in the lubricant film instead of being utilised for wear processes; total distance slid, the sliding distance or accumulated strain achieved prior to development of a set tractive force limit; half life of lubricant, the time taken for a lubricant to lose half of its sliding performance; and apparent viscosity, a measure of the lubricity presented with respect to accumulated strain. The rail/wheel simulator used in this research consists of two dissimilar wheels (disks) rotating in contact with one another simulating a conformal gauge corner contact. The first wheel, a simulated rail, is driven by an electric motor which then drives the second wheel, a simulated railroad wheel, through the contact. Hydraulic braking on the railroad wheel is used to simulate the rolling/sliding conditions. The variables of the simulated contact that are controlled with this equipment are normal force, input wheel speed, slip ratio between samples, sample geometries and material properties, and lubricant types. Rail curve lubricants were laboratory tested to define their properties using the ASTM and other appropriate standards. The performance differences measured using ASTM standards based tests were susceptible to repeatability problems and did not represent the contact as accurately as the rail/wheel simulator. This laboratory simulator was used to gather data in lubricated and unlubricated conditions for the purpose of providing lubricant performance measurements. These measurements were presented and the tested lubricants were ranked conclusively using three industrially relevant performance criteria. Total sliding distance and total absorbed energy measurements of the rail curve lubricants displayed clear differences in lubricant performance for both of these criteria. Total sliding distance is equivalent to the number of axles in the field situation, while total absorbed energy is the energy unavailable for wear processes of rails and wheels. Lubricants designed using these measurements will increase lubricant performance with respect to these performance criteria which in turn will reduce wear to both rails and wheels. Measurement of the apparent viscosity of rail curve lubricants, using the rail/wheel simulator, displayed changes in rheological characteristics with respect to accumulated strain. Apparent viscosity is a measure of the shear stress transmitted from the wheels to the rails. Designing a rail curve lubricant after analysing measurements taken from the rail/wheel simulator will assist in identifying lubricant properties to reduce the wear producing shear stresses generated in a rail wheel contact. Decay of lubricant performance was measured for three different rail curve lubricants under simulated conditions. The research found appreciable and quantifiable differences between lubricants. Industrial application of the findings will improve positioning of lubrication systems, improve choice of lubricants and predict effective lubrication distance from the lubricant application point. Using the new methods of lubricant performance measurement developed in this thesis, the objective of this research, to quantify rail curve lubricant performance through laboratory simulation, has been achieved.
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Tratamento de efluente da industrialização de pescado com sistema de ultrafiltração /Pires, Helenice Aparecida January 2017 (has links)
Orientador: Elisa Helena Giglio Ponsano / Banca: Sandra Maria de Melo / Banca: Manoel Garcia Neto / Resumo: A indústria de pescado vem se desenvolvendo para atender à crescente demanda do mercado e, concomitantemente, vem aumentando a quantidade de resíduos descartados em função do processamento. O efluente gerado pelas indústrias de pescado contém matéria orgânica com potencial poluente e, por isso, deve ser tratado previamente ao descarte. Os sistemas de filtração vêm ganhando notoriedade nesse sentido. Assim, o objetivo deste trabalho foi verificar o potencial da operação de ultrafiltração para reduzir a carga poluente do efluente de indústria de tilápia. O efluente foi coletado em uma indústria de processamento de tilápias e caracterizado quanto a suas propriedades físico-químicas. As filtrações foram realizadas em sistema fechado com recirculação do retentado, utilizando-se membranas de três porosidades: M1 - 150 kDa, M2 - 30 kDa e M3 - 10kDa. As análises físico-químicas foram repetidas no permeado e no retentado gerados nas filtrações. Exceto para a cor, que reduziu em 91,7% com a membrana de 10 kDa, as três membranas promoveram a mesma rejeição para os demais parâmetros avaliados, embora não tenham sido capazes de atender aos padrões para lançamento direto de efluentes em relação à cor e ao teor de óleos e graxas. Todas as membranas também foram igualmente capazes de concentrar matéria orgânica e inorgânica do efluente. A membrana de 150 kDa mostrou ser a mais adequada para remover e concentrar a carga poluente do efluente de indústria de processamento de tilápias. / Abstract: Fish processing industry is in constant development in order to comply with the growing market demand and, concurrently, the amount of residues to be discarded is also increasing. The effluent raised from these industries contains organic matter with pollutant potential and so must be treated before being discarded. Along those lines, the filtration systems are gaining notoriety. So, the purpose of this study was to test the potential of ultrafiltration in reducing the pollutant load of the effluent from a tilapia processing industry. The effluent was collected in a tilapia processing industry and characterized regarding to its physicochemical properties. Filtrations were carried out in closed system with recirculation of the retentate using membranes of three porosities: M1 - 150 kDa, M2 - 30 kDa and M3 - 10kDa. The physicochemical analyses were repeated for the permeate and the retentate generated from the treatments. Except for color, that decreased 91.7% with the 10 kDa membrane, all the three membranes provided the same rejection for the other parameters studied, although they were not able to reach the standards for the direct launching of effluents regarding to color and to oils and grease. All treatments were also equally able to concentrate the organic and inorganic matter of the effluent. The 150 KDa membrane showed to be the most appropriate for removing and concentrating the pollutant load of the effluent from tilapia processing. / Mestre
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Tratamento de efluente da industrialização de pescado com sistema de ultrafiltração / Treatment of fish industrialization effluent with ultrafiltration systemPires, Helenice Aparecida [UNESP] 22 August 2017 (has links)
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Previous issue date: 2017-08-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A indústria de pescado vem se desenvolvendo para atender à crescente demanda do mercado e, concomitantemente, vem aumentando a quantidade de resíduos descartados em função do processamento. O efluente gerado pelas indústrias de pescado contém matéria orgânica com potencial poluente e, por isso, deve ser tratado previamente ao descarte. Os sistemas de filtração vêm ganhando notoriedade nesse sentido. Assim, o objetivo deste trabalho foi verificar o potencial da operação de ultrafiltração para reduzir a carga poluente do efluente de indústria de tilápia. O efluente foi coletado em uma indústria de processamento de tilápias e caracterizado quanto a suas propriedades físico-químicas. As filtrações foram realizadas em sistema fechado com recirculação do retentado, utilizando-se membranas de três porosidades: M1 - 150 kDa, M2 - 30 kDa e M3 - 10kDa. As análises físico-químicas foram repetidas no permeado e no retentado gerados nas filtrações. Exceto para a cor, que reduziu em 91,7% com a membrana de 10 kDa, as três membranas promoveram a mesma rejeição para os demais parâmetros avaliados, embora não tenham sido capazes de atender aos padrões para lançamento direto de efluentes em relação à cor e ao teor de óleos e graxas. Todas as membranas também foram igualmente capazes de concentrar matéria orgânica e inorgânica do efluente. A membrana de 150 kDa mostrou ser a mais adequada para remover e concentrar a carga poluente do efluente de indústria de processamento de tilápias. / Fish processing industry is in constant development in order to comply with the growing market demand and, concurrently, the amount of residues to be discarded is also increasing. The effluent raised from these industries contains organic matter with pollutant potential and so must be treated before being discarded. Along those lines, the filtration systems are gaining notoriety. So, the purpose of this study was to test the potential of ultrafiltration in reducing the pollutant load of the effluent from a tilapia processing industry. The effluent was collected in a tilapia processing industry and characterized regarding to its physicochemical properties. Filtrations were carried out in closed system with recirculation of the retentate using membranes of three porosities: M1 - 150 kDa, M2 - 30 kDa and M3 - 10kDa. The physicochemical analyses were repeated for the permeate and the retentate generated from the treatments. Except for color, that decreased 91.7% with the 10 kDa membrane, all the three membranes provided the same rejection for the other parameters studied, although they were not able to reach the standards for the direct launching of effluents regarding to color and to oils and grease. All treatments were also equally able to concentrate the organic and inorganic matter of the effluent. The 150 KDa membrane showed to be the most appropriate for removing and concentrating the pollutant load of the effluent from tilapia processing. / FAPESP: 2015/25853-1
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Analýza kvality svarových spojů / On the analysis of welding seamsNěmečková, Monika January 2019 (has links)
The thesis deals with the analysis of the quality of welded joints on the pressure tank, which is produced by Bosch Diesel s.r.o. The main point is to improve the porosity in the weld joint. The theoretical part deals with the analysis of the pressure container and its production process. The practical part deals with the cleaning process before welding and the analysis of residual grease on the welding surfaces after the cleaning process in which two different cleaning media were used. Furthermore, the CT evaluation of welded joints was used to support which washing medium is better, thus providing better degreasing and thus less porosity in the weld joint, for pretreatment of weld surfaces.
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Benchmarking of temperature and friction in axial ball bearings lubricated by a novel polymer thickened grease / Benchmarking av temperatur och friktion i axialkullager smörjt med ett nytt polymerbaserat fettChen, Qi January 2015 (has links)
This project concerns the benchmarking of a novel polymer thickened grease with a lithium thickened one. The new grease has shown low temperature property in the previous bearing tests on SKF-R2F. A DAQ interface was implemented using lab View for a modified four-ball machine. The result shows the temperature and friction torque profiles of the greases at different speeds. The raw data is attached with a suggested improvement for friction measurement. / Det här projektet avser att jämföra ett nytt polymerbaserat fett med ett lithiumbaserat fett. Det nya fettet har påvisat låga temperaturegenskaper i det tidigare testet med ett lager av typen SKF-R2F. Ett DAQ-gränssnitt implementerades med Lab View för en modifierad fyr-kulig maskin. Resultaten visar temperaturer och friktionsmoment av fetterna vid olika hastigheter. Förslag på förbättring av friktionsmomentet är presenterat tillsammans med rådata.
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Effect of Long Chain Fatty Acids on Anaerobic Digestion of Municiapal Sewage Sludge in Completely Mixed ReactorsZhu, Kuang 10 June 2013 (has links)
Fats, oil and grease (FOG) are generated in large amounts by cooking and food processing. Anaerobic co-digestion with municipal sewage sludge has proven to be one of best alternatives for FOG disposal due to its high potential for biogas production. However, excessive addition of long chain fatty acid, the major content of FOG, has been reported to have inhibitory effects on the anaerobic digestion process and to cause operational challenges. In this study, high purity long chain fatty acids (LCFAs) including linoleic acid, oleic acid, and a mixture of oleic acid and stearic acid were added to laboratory completed mixed anaerobic digesters. The performance of the digesters in terms of solids destruction, COD degradation, LCFAs accumulation and gas production was investigated. After reaching steady state, a large amount of palmitic acid was found in the reactors with oleic acid addition and mixture of stearic and oleic acid addition. In the meantime, no palmitic acid increase was observed in reactors where linoleic acid was added. A better solids and COD reduction and a higher biogas production were observed in reactors with higher LCFAs addition. For reactors with the same dosage of LCFAs addition, linoleic acid addition resulted in the greatest improvement in digester performance; the mixture of stearic acid and oleic acid achieved the least increase in biogas production and solids and COD reduction. A high concentration of both palmitic and stearic acid in the reactors with oleic acid addition and with 20% mixed acid addition was observed. In contrast, linoleic acid and 30% mixed acid addition did not lead to a greater palmitic or stearic acid concentrations. Up to 30% of pure linoleic acid, oleic acid and mixed acid addition are able to enhance the performance of anaerobic digesters. It is recommended that the dosage of oleic acid be below 30% to avoid LCFAs accumulation and to increase reactor stability. / Master of Science
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Algae hydrocarbons designed for bio-based lubricants / Kolväten från alger anpassade för biobaserade smörjmedelSjöhag, Elin January 2020 (has links)
Smörjmedel är en nödvändighet för maskiner för att minska slitage och energiförbrukning. Dock är över 95% av de använda smörjmedlen i dag fossilbaserade. Smörjmedel baserade på vegetabiliska oljor finns tillgängliga men har ofta en lägre oxidativ stabilitet och sämre lågtemperaturegenskaper än deras fossilbaserade motsvarigheter. Ett annat hinder att övervinna är att ersätta vanligt använda förtjockningsmedel i halvfast smörjmedel med biobaserat alternativ vilket också visat sig vara en utmanande uppgift. Representanter för marina biomassa som mikro- och makroalger har potential att användas i framtiden som förnybar råvara källor på grund av deras kemiska sammansättningar såväl som gynnsamma odlingsförhållanden. Mikroalger har ett högt lipidinnehåll och vissa arter har ett högt innehåll av kolväten som liknar råolja. Makroalger har ett högt innehåll av polysackarider med en förtjockningsförmåga i vatten. Även om mikroalger innehåller lovande kolväten och lipider som kan användas i smörjmedelsapplikationer är det idag inte ekonomiskt möjligt att använda mikroalger för att producera produkter med lågt värde. Även makroalger är för kostsamma att kultivera för billiga produkter, För att kunna använda polysackarider som tillsatser i olja måste de vara mer hydrofoba. I denna studie oxiderades alginat först i en ringöppningsreaktion, för att senare reduceras i en Schiff-basformation och reduktion till en mer amfifil polysackarid. Resultaten visade en hög nedbrytning av polysackariden både i oxidationsreaktionen och i reduktionsreaktionen, från en startmolekylvikt av 580 000 g/mol till ~ 10 000 g/mol. Etanol kunde användas i oxidationsreaktionen för att öka den möjliga alginatkoncentrationen. Både FTIR- och 1H-NMR-resultaten indikerade en lyckad oxidation och reduktion. Framtida arbete involverar inblandning av det hydrofobt modifierade alginatet i en basolja och utvärdering av effekten av den erhållna biobaserade basoljekomponenten på oljeegenskaperna, till exempelökning av viskositeten, oxidationsstabilitet och förtjockningsbeteenden. / Lubricants are a necessity for machineries in order to reduce friction and wear. However, over 95% of the lubricants used today are fossil-based. Vegetable oil-based lubricants are available but often possess lower oxidative stability and poorer low temperature properties than their fossil-based counterparts. Vegetable oils are therefore not a perfect solution to reduce crude oil usage. Another obstacle to overcome would be a replacement of commonly used thickeners in semisolid lubricants with bio-based alternative, which has proven to be a challenging task. Marine biomass representatives such as micro-and macroalgae have the potential to be used in the future as renewable feedstock sources due to their chemical compositions as well as beneficial cultivation conditions such as usage of non-arable land and saltwater. Microalgae have a high lipid content, and in some species a high content of hydrocarbons similar to crude oil. Macroalgae have a high content of polysaccharides, some with gelling abilities. Even though microalgae contain promising hydrocarbons and lipids that can be used in lubricant applications, it is currently not economically feasible to use microalgae to produce low valueproducts. Macroalgae are also too expensive to cultivate to be used in low price products. In order to use polysaccharides as additives in oil, they need to be more amphiphilic. In this study, alginate, derived from brown seaweed, was first oxidized in a ring opening reaction to later be reduced in a Schiff base formation and reduction to introduce more hydrophobic side groups. The results revealed a severe degradation of the polysaccharide both in the oxidation and in the reduction reaction, from a starting molecular weight of 580 000 g/mol to ~ 10 000 g/mol. Ethanol was proved to be a suitable solvent in the oxidation reaction which increased the possible alginate concentration. Both FTIR and 1H-NMR results indicated a successful oxidation and reduction. Future work involves incorporation of the hydrophobically modified alginate in a base oil and evaluation of the presence of the obtained bio-based base oil component on the oil properties, for example viscosity increase, oxidation stability and thickening behaviors.
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Preparation and Experimental Investigation of the Tribological Properties of Conductive Grease Containing Ionic LiquidsJohansson Segervall, Gabriella January 2022 (has links)
This thesis project was executed at ABB AB. The purpose of the thesis was to formulate aselection of ionic liquids with different thickeners as greases and experimentally understand thetribological characteristics and electrical properties. The performance of four ionic liquids, 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (IL6), 1-Butyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide (IL2), 1-Hexyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide (IL3), and 1-Hexyl-1-methylpyrrolidiniumbis(trifluoromethylsulfonyl)imide (IL4) and two thickeners, polytetrafluoroethylene (PTFE)powder and lithium stearate were evaluated for tribological and electrical properties. Two ionicliquids, 1-Ethyl-3-methylimidazolium dicyanamide, 1-Butyl-3-methylimidazolium dicyanamidefailed to form stable greases due to poor miscibility with the thickeners. Frictional tests for all thecomposed grease were performed and afterwards analyzed with a light optical microscope forassessment of the wear tracks. Electrical conductivity was measured with a contact resistancetest setup. Moreover, the dropping point for the greases was measured to ensure theformulations were qualified as lubricant greases. Ionic liquid greases containing PTFE as athickener show better thermal stability than those containing lithium stearate. In regards to antiwearand friction reduction, the results indicate better tribological properties for the IL3 and IL4with the 25 wt% of PTFE and lithium stearate. The electrical conductivities were similar for allthe ionic liquid grease formulations which were higher than the general purpose grease as thereference. The work has paved the way for further investigation of ionic liquid based greaseswhich show potential in mitigation of bearing current in electric machines.
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Fiber based biocomposite material with water and grease barrier properties / Fiberbaserat biokompositmaterial med vatten-och fettbarriäregenskaperMartinsdotter, Linnea January 2021 (has links)
Syftet med denna studie var att utveckla en biokomposit med både fett-och vattenbarriär. Material med dessa egenskaper innehåller idag ofta PFAS-molekyler (per- och polyfluorerade alkylsubstanser). Det är av stor betydelse att byta ut dessa mot ett biobaserat alternativ då de är giftiga och ackumuleras i naturen. Biokompositen utvecklades genom att kombinera icke-trä pappersmassa (75%) och trä pappersmassa (25%) som matris. Därefter tillsattes olika biobaserade additiv i våtände för att påverka materialets egenskaper. Proverna testades på deras dragstyrka, vattenavvisning och fettavvisning. Den stora utmaningen var att lyckas med fettavisningen. 1% Polysackarid 1 tillsammans med 0.5% sizing komponent var det provet som gav bäst resultat. För att utvärdera denna metod gjordes en jämförelse med ytbehandling. Det gjordes genom att stryka på några av de tidigare använda additiven på ytan av matrisen. Ytbehandlingen visade sig ha en större påverkan på fettavvisningen men med liknande eller sämre påverkan på vattenavvisningen. Nackdelen med denna metod är att den kräver ett flertal extra steg i produktionen. / The aim of this thesis work was to develop a pulp-based biocomposite material with good water and grease barrier properties. It is important to achieve such properties to able to replace PFAS (poly- and perfluoroalkyl substances) molecules due to their toxicity and accumulation. Different types of pulp were evaluated as the matrix and the optimal matrix was based on non-wood pulp (75%) with wood pulp 1 (25%). This was also combined with several different additives in the wet-end. The samples were tested for their tensile strength, water resistance and grease resistance. The biggest challenge was to achieve adequate grease resistance. 1% Polysaccharide 1 together with 0.5% sizing agent was one of the better samples. It was clear the additives affected each other when used in combination with each other which indicates that wet end chemistry is complex. For a comparison, some additives were also tested as coatings. This technique resulted in better grease resistance but requires several extra steps in the production.
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Impact Of Contaminants on Blade Bearing’s LifetimeTomy, Abel January 2024 (has links)
The global shift towards sustainable practices extends across various domains, including energy generation. Wind energy, a cornerstone of this transition, relies heavily on the efficient operation of wind turbines. This study investigates the impact of contaminants on the longevity and performance of blade bearings in wind turbines. Under real-world conditions, blade bearings frequently operate in suboptimal lubrication environments, attacked by contaminants like wear particles and water. This research, conducted in collaboration with Vattenfall R&D, aims to focus on the specific effects of these contaminants. Through comprehensive literature reviews and tribological tests, the study evaluates the load in rolling elements, examines the contact conditions between raceways and rollers, and determines the effects of contaminants on wear volume. Findings indicate that most pitch movements in blade bearings are limited to small angles, influencing lubrication requirements and wear patterns. Chloride-based EP additives, probably inactive due to insufficient activation temperatures, show potential for hydrolysis-induced corrosion. Wear tests suggest that used grease may perform better under certain conditions compared to fresh grease, highlighting the complexity of lubricant performance. Long-term tribological tests show that FUCHS LUBRITECH GLEITMO 585K exhibits better wear resistance compared to Shell Rhodina BBZ in test conditions. The study underscores the importance of proper lubrication and contamination management in extending blade bearing life. Recommendations include regular grease monitoring and analysis, understanding tribo-corrosion effects, and improving seal compatibility to enhance overall bearing reliability.
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