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Parmigiani John - One of the best experts on this subject based on the ideXlab platform.
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An Evaluation of the Performance of Chainsaw Lubricants
'Faculty of Forestry University of Zagreb', 2020Co-Authors: Orawiec Alex, Suryan Levi, Parmigiani JohnAbstract:Chainsaws Require Lubrication of the guide bar and saw chain to function properly. Many oils are commercially available to provide this Lubrication. Economical and more recently environmental concerns are increasingly compelling consideration of the best type of oil to use. Several published scientific studies provide some guidance, but additional information is needed for operators to make informed and effective choices in lubricating oil selection. The work presented in this paper contributes to providing this guidance by comparing the performance of economy and premium versions of three commonly-used types of lubricating oils: petroleum-based bar-and-chain oil, biodegradable bar-and-chain oil, and petroleum-based motor oil. Testing was conducted on a laboratory chainsaw test apparatus used in prior published scientific studies of chainsaw performance. Testing consisted of free running (i.e. chain traveling about the bar at cutting speed but not cutting) for a prescribed time period, while lubricating oil was applied to the guide bar and saw chain in the usual manner and at typical flow rates. Based on the correlations between wear, friction, and temperature, the mean guide bar temperature was used as the measure of performance of each oil. Results showed that, while each oil type performed adequately, the petroleum-based bar-and-chain oil performed best and the biodegradable-based oil performed worst with the petroleum-based motor oil providing intermediate performance. No consistent correlation was found between either the unit cost of each oil and its performance or the perceived quality of each oil (economy versus premium) of each oil and its performance. Tribological properties of flash point, viscosity, and four-ball wear were measured. A weak correlation was found between flash point values and performance. A possible Stribeck relationship was found for viscosity implying a possible transition from mixed and hydrodynamic Lubrication. No correlations were found between performance and four-ball wear test results. These results support chainsaw operator observations and other published scientific findings that a variety of oils can be effectively used as lubricants. The lack of correlation of performance with some commonly-measured tribological properties suggests lubricating-oil providers should consider the use of a dedicated saw chain testing apparatus in product development
V. Ageh - One of the best experts on this subject based on the ideXlab platform.
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Processing, Structure and Tribological Property Relations of Ternary Zn-ti-o and Quaternary Zn-ti-zr-o Nanocrystalline Coatings
2014Co-Authors: V. AgehAbstract:Conventional liquid lubricants are faced with limitations under extreme cyclic operating conditions, such as in applications that Require Lubrication when changing from atmospheric pressure to ultrahigh vacuum and ambient air to dry nitrogen (e.g., satellite components), and room to elevated (>500°C) temperatures (e.g., aerospace bearings). Alternatively, solid lubricant coatings can be used in conditions where synthetic liquid lubricants and greases are not applicable; however, individual solid lubricant phases usually perform best only for a limited range of operating conditions. Therefore, solid lubricants that can adequately perform over a wider range of environmental conditions are needed, especially during thermal cycling with temperatures exceeding 500°C. One potential material class investigated in this dissertation is lubricious oxides, because unlike other solid lubricant coatings they are typically thermodynamically stable in air and at elevated temperatures. While past studies have been focused on binary metal oxide coatings, such as ZnO, there have been very few ternary oxide and no reported quaternary oxide investigations. The premise behind the addition of the third and fourth refractory metals Ti and Zr is to increase the number of hard and wear resistant phases while maintaining solid Lubrication with ZnO. Therefore, the major focus of this dissertation is to investigate the processing-structure-tribological property relations of composite ZnO, TiO2 and ZrO2 phases that form ternary (ZnTi)xOy and quaternary (ZnTiZr)xOy nanocrystalline coatings. The coatings were processed by atomic layer deposition (ALD) using a selective variation of ALD parameters. The growth structure and chemical composition of as-deposited and ex situ annealed ternary and quaternary oxide coatings were studied by combined x-ray diffraction/focused ion beam microscopy/cross-sectional transmission electron microscopy, and x-ray photoelectron spectroscopy/Auger electron spectroscopy, respectively. It was determined that the structure varied from purely nanocrystalline (ternary oxides) to composite amorphous/nanocrystalline (quaternary oxides) depending on ALD parameters and annealing temperatures. In particular, the ZnTiO3 ilmenite phase with (104) textured nanocolumnar grains, exhibiting high stacking fault/partial dislocation densities >1012/cm2, was responsible for the excellent tribological behavior. Steady-state sliding friction coefficients down to 0.12 in humid air and 0.2 in dry nitrogen were measured along with sliding and fretting wear factors in the range of 10-6 to 10-7 mm3/N·m, even after ex situ annealing to 550°C. Additionally, the quaternary oxide phase Zn(Ti,Zr)O3 in solid solution exhibited a low fretting wear rate of 1x10-6 mm3/N·m. In contrast, certain phases, such as Zn2TiO4 cubic spinel, that form at annealing temperatures >550°C were responsible for high friction and wear. Mechanistic studies using the above techniques revealed low friction and wear-reducing surfaces and subsurfaces were due to different velocity accommodation modes (VAM). In the case of the ternary system, sliding-induced plastic deformation was possible when ZnTiO3 (104) stacking faults, bordered by partial dislocations, serve as a pathway for the dislocations to glide parallel to the sliding direction and hence achieve low friction and wear via an intrafilm shear VAM. It was evident that the individual nanocolumnar ZnTiO3 grains were plastically sheared as opposed to being fractured during wear. Conversely for the quaternary system, an interfacial sliding VAM between the counterface and a mechanically mixed layer (tribofilm) composed of the refined coating and counterface material, that also served as a source for the formation of cylindrical rolls, was responsible for wear reduction. Therefore, these lubricious oxides are a potential candidate for solid Lubrication at high temperatures (up to 550 °C) and in space environments.
Orawiec Alex - One of the best experts on this subject based on the ideXlab platform.
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An Evaluation of the Performance of Chainsaw Lubricants
'Faculty of Forestry University of Zagreb', 2020Co-Authors: Orawiec Alex, Suryan Levi, Parmigiani JohnAbstract:Chainsaws Require Lubrication of the guide bar and saw chain to function properly. Many oils are commercially available to provide this Lubrication. Economical and more recently environmental concerns are increasingly compelling consideration of the best type of oil to use. Several published scientific studies provide some guidance, but additional information is needed for operators to make informed and effective choices in lubricating oil selection. The work presented in this paper contributes to providing this guidance by comparing the performance of economy and premium versions of three commonly-used types of lubricating oils: petroleum-based bar-and-chain oil, biodegradable bar-and-chain oil, and petroleum-based motor oil. Testing was conducted on a laboratory chainsaw test apparatus used in prior published scientific studies of chainsaw performance. Testing consisted of free running (i.e. chain traveling about the bar at cutting speed but not cutting) for a prescribed time period, while lubricating oil was applied to the guide bar and saw chain in the usual manner and at typical flow rates. Based on the correlations between wear, friction, and temperature, the mean guide bar temperature was used as the measure of performance of each oil. Results showed that, while each oil type performed adequately, the petroleum-based bar-and-chain oil performed best and the biodegradable-based oil performed worst with the petroleum-based motor oil providing intermediate performance. No consistent correlation was found between either the unit cost of each oil and its performance or the perceived quality of each oil (economy versus premium) of each oil and its performance. Tribological properties of flash point, viscosity, and four-ball wear were measured. A weak correlation was found between flash point values and performance. A possible Stribeck relationship was found for viscosity implying a possible transition from mixed and hydrodynamic Lubrication. No correlations were found between performance and four-ball wear test results. These results support chainsaw operator observations and other published scientific findings that a variety of oils can be effectively used as lubricants. The lack of correlation of performance with some commonly-measured tribological properties suggests lubricating-oil providers should consider the use of a dedicated saw chain testing apparatus in product development
Suryan Levi - One of the best experts on this subject based on the ideXlab platform.
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An Evaluation of the Performance of Chainsaw Lubricants
'Faculty of Forestry University of Zagreb', 2020Co-Authors: Orawiec Alex, Suryan Levi, Parmigiani JohnAbstract:Chainsaws Require Lubrication of the guide bar and saw chain to function properly. Many oils are commercially available to provide this Lubrication. Economical and more recently environmental concerns are increasingly compelling consideration of the best type of oil to use. Several published scientific studies provide some guidance, but additional information is needed for operators to make informed and effective choices in lubricating oil selection. The work presented in this paper contributes to providing this guidance by comparing the performance of economy and premium versions of three commonly-used types of lubricating oils: petroleum-based bar-and-chain oil, biodegradable bar-and-chain oil, and petroleum-based motor oil. Testing was conducted on a laboratory chainsaw test apparatus used in prior published scientific studies of chainsaw performance. Testing consisted of free running (i.e. chain traveling about the bar at cutting speed but not cutting) for a prescribed time period, while lubricating oil was applied to the guide bar and saw chain in the usual manner and at typical flow rates. Based on the correlations between wear, friction, and temperature, the mean guide bar temperature was used as the measure of performance of each oil. Results showed that, while each oil type performed adequately, the petroleum-based bar-and-chain oil performed best and the biodegradable-based oil performed worst with the petroleum-based motor oil providing intermediate performance. No consistent correlation was found between either the unit cost of each oil and its performance or the perceived quality of each oil (economy versus premium) of each oil and its performance. Tribological properties of flash point, viscosity, and four-ball wear were measured. A weak correlation was found between flash point values and performance. A possible Stribeck relationship was found for viscosity implying a possible transition from mixed and hydrodynamic Lubrication. No correlations were found between performance and four-ball wear test results. These results support chainsaw operator observations and other published scientific findings that a variety of oils can be effectively used as lubricants. The lack of correlation of performance with some commonly-measured tribological properties suggests lubricating-oil providers should consider the use of a dedicated saw chain testing apparatus in product development
Belinelli, Marjorie Maria - One of the best experts on this subject based on the ideXlab platform.
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Development of method for selecting the industrial Lubrication policy centered on reliability: application in food industry.
'Universidade de Sao Paulo Agencia USP de Gestao da Informacao Academica (AGUIA)', 2016Co-Authors: Belinelli, Marjorie MariaAbstract:Em indústria de alimentos são aplicados máquinas e equipamentos para processamento de alimentos, os quais exigem lubrificação para garantir seu pleno estado de funcionamento. Porém o mesmo lubrificante que auxilia o funcionamento do maquinário é considerado um risco potencial de contaminação do produto em suas etapas de processamento, vindo a interferir em sua qualidade. Além deste fator, uma inadequada gestão do processo de lubrificação de máquinas e equipamentos podem gerar eventos de falhas, impactando na disponibilidade e confiabilidade operacional do sistema industrial como todo. O objeto da pesquisa desenvolvida nesta tese de doutorado é o desenvolvimento de um método de seleção de política de lubrificação industrial centrada em confiabilidade voltada especificamente para maquinário empregado na fabricação de alimentos, e visa analisar os eventos de falhas ocorridos no maquinário, os quais relacionados com o processo de lubrificação industrial, bem como, a relação das atividades de lubrificação na geração de foco de potencial risco que propicie perda de qualidade e inocuidade do produto. O método é estruturado na identificação das variáveis envolvidas no processo de lubrificação industrial e análise de seus impactos sobre a geração de eventos de falhas e potencial foco de risco de perda de qualidade e inocuidade do produto, Esta análise visa direcionar a tomada de decisão quanto a estrutura da política de lubrificação industrial adequada a cada ativo industrial instalado na indústria de alimentos. A validação do método de seleção de política de lubrificação centrada em confiabilidade deu-se através da aplicação de sua metodologia em um sistema reparável, uma máquina cobrideira, instalada em uma indústria de alimentos, localizada na região metropolitana de Curitiba. A análise estatística do comportamento da tendência de falhas neste ativo industrial conjuntamente com a análise funcional dos modos de falhas relacionados com o processo de lubrificação industrial, possibilitou estruturar uma política de lubrificação industrial adequada para máquina cobrideira. Esta política de lubrificação contempla ações que resultaram no aumento de produtividade anual da máquina cobrideira em 0,16%, isto significa 280.830 unidades (equivalente a 7,02 toneladas) produzidas a mais no ano de 2014 em relação a 2013, e na melhoria dos indicadores de desempenho de manutenção e disponibilidade operacional da máquina cobrideira. Além disto, a aplicação do método desenvolvido estruturou procedimentos de modo de execução e monitoramento das atividades de lubrificação, os quais visam garantir a qualidade do produto durante as etapas de fabricação conjuntamente com a melhoria de desempenho e produtividade do sistema industrial.In the food industry, machinery and equipment for food processing are used. They Require Lubrication to ensure they\'re working properly. However, the same lubricant which assists the operation of the machinery is considered a potential contamination to the product in its processing steps, impacting on their quality. The improper management of the Lubrication process of machinery and equipment may lead to fault events, impacting on the availability and operational reliability of the industrial system as a whole. The research object developed in this doctorate thesis shows the development of a selection method of an industrial Lubrication policy focused on reliability. Such policy is designed specifically for machinery used in the manufacture of foods. It analyzes the failure events in the machinery due to the Lubrication process and. It also analyzes the connection between the lubricating activities and the potential risk of loss product quality and safety. The method is structured to identify the variables involved in the industrial Lubrication process and analyzes their impact they have on fault events and potential source of risk of product quality loss. This analysis aims to guide decision-making regarding the structure of the adequate industrial Lubrication policy to each industrial asset installed in the food industry. The validation of the Lubrication policy selection method focused on reliability occurred through the application of its methodology in a repairable system, a coating machine, installed in a food industry located in the metropolitan region of Curitiba. The statistical analysis of the fault trend behavior in this industrial asset together with the functional analysis of failure modes related to the industrial Lubrication process made it possible to structure a suitable policy for the industrial Lubrication of the coating machine. This Lubrication policy includes actions that resulted in the increase of the annual productivity of the coating machine by 0.16%. It means 280,830 more units (equivalent to 7.02 tons) were produced in 2014 than in 2013. It also improved the maintenance performance indicators and the operational availability of the coating machine. Furthermore, the application of the method structured procedures of execution mode and monitoring of Lubrication activities. The aim was to ensure the quality of the product during the manufacturing steps together with the improvement of the performance and productivity of the industrial system