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Evaluation of lubricants for forming
Svobodová, Hana ; Podaný, Kamil (referee) ; Lidmila, Zdeněk (advisor)
The aim of this diploma thesis is experimental testing and evaluation of the suitability of lubricants for drawing stainless chromium - nickel austenitic steel X5CrNi18-10 and comparison of the results obtained from the work [51]. The testing was performed by modeling the friction between the traction edge and the retainer, which corresponds to the real production process at ACO Industries. The introductory part of the thesis describes the process of deep drawing, followed by a description of tribology and the effect of friction. The individual types and properties of lubricants are described in more detail. The main part of the work deals with the testing of lubricants. The results are then described and evaluated.
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The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets.
Rumlerová, Lenka ; Ondrejček, Pavel (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D Student: Lenka Rumlerová Title of Thesis: The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets. This thesis deals with influence of rice extract, as a new kind of glidant on compressibility of microcrystalline celulose as a model filler. Furthermore it evaluates the impact of rice extract on tablet properties. Effects of rice extract were compared with two standard glidants - magnesium stearate and colloidal silicon dioxide. As first the influence of diferent glidants concetrations on flow properties of mixtures were assesed. Tablets were compresed using three different compression forces. A force- displacement record was used to evaluate the compressibility of microcrystalline cellulose and its mixtures with glidants. Subsequently, the properties of tablets were evaluated. The radial strenght, abrasion, and tablet disintegration time were measured. The results revealed that the rice extract has the least effect on mixtures flow poperties. However, all mixtures showed a statistically significant improvement in flowability. When using a 1 % rice extract, the flow properties of the...
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The effect of particle size on lactose compressibility
Havlíková, Natálie ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Natálie Havlíková Title of Thesis: The effect of particle size on lactose compressibility It is known that the particle size of the compressed material plays an important role in the manufacture of tablets. It affects the properties of intermediate and final products. In this thesis the properties of tablets made of two lactose types, which were used as model fillers, were studied. These were Tablettose® 80 and Lactopress® Anhydrous. In both lactose types, five sieved size fractions of the particle size ranging from 9 to 346µm and their original unsieved mixture were used. The compaction forces ranging from 2 to 10kN were used for tablet preparation. Magnesium stearate was used for external lubrication. The evaluation of the prepared tablets was done mainly by using the pharmacopoeial methods. The evaluated parameters were friability, disintegration time and hardness. Furthermore, the elasticity of the tablets and the evaluation using the force-displacement method parameters were assessed. From the results of this work, it is not possible to unambiguously determine the advantage of one particular fraction size in the comparison to the...
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Using tribodiagnostics in predictive maintenance in company practice
Trost, Daniel ; Nahodil, Petr (referee) ; Hammer, Miloš (advisor)
The thesis deals with the use of tribodiagnostics in predictive maintenance in corporate practice. It is generally dealt with maintenance, then tribodiagnostics in the company Škoda Auto a.s. Used offline and online diagnostic tools are described. Emphasis is placed on verifying the functionality of the newly purchased online filter unit. The experimental part is focused on detailed analysis of the above, including comparison of measurement results offline and online diagnostics. There is also an economic evaluation of savings obtained by operation the online filter unit. In conclusion, the tribodiagnostics recommendations are given for Škoda Auto a.s.
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The effect of particle size on lactose compressibility
Havlíková, Natálie ; Ondrejček, Pavel (advisor) ; Svačinová, Petra (referee)
Charles University in Prague, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Natálie Havlíková Title of Thesis: The effect of particle size on lactose compressibility It is known that the particle size of the compressed material plays an important role in the manufacture of tablets. It affects the properties of intermediate and final products. In this thesis the properties of tablets made of two lactose types, which were used as model fillers, were studied. These were Tablettose® 80 and Lactopress® Anhydrous. In both lactose types, five sieved size fractions of the particle size ranging from 9 to 346µm and their original unsieved mixture were used. The compaction forces ranging from 2 to 10kN were used for tablet preparation. Magnesium stearate was used for external lubrication. The evaluation of the prepared tablets was done mainly by using the pharmacopoeial methods. The evaluated parameters were friability, disintegration time and hardness. Furthermore, the elasticity of the tablets and the evaluation using the force-displacement method parameters were assessed. From the results of this work, it is not possible to unambiguously determine the advantage of one particular fraction size in the comparison to the...
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The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets.
Rumlerová, Lenka ; Ondrejček, Pavel (advisor) ; Mužíková, Jitka (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D Student: Lenka Rumlerová Title of Thesis: The effect of rice extract on the compressibility and mechanical properties of microcrystalline cellulose tablets. This thesis deals with influence of rice extract, as a new kind of glidant on compressibility of microcrystalline celulose as a model filler. Furthermore it evaluates the impact of rice extract on tablet properties. Effects of rice extract were compared with two standard glidants - magnesium stearate and colloidal silicon dioxide. As first the influence of diferent glidants concetrations on flow properties of mixtures were assesed. Tablets were compresed using three different compression forces. A force- displacement record was used to evaluate the compressibility of microcrystalline cellulose and its mixtures with glidants. Subsequently, the properties of tablets were evaluated. The radial strenght, abrasion, and tablet disintegration time were measured. The results revealed that the rice extract has the least effect on mixtures flow poperties. However, all mixtures showed a statistically significant improvement in flowability. When using a 1 % rice extract, the flow properties of the...
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The influence of rice extract as a new lubricant on the compressibility of microcrystalline cellulose
Bučková, Lenka ; Ondrejček, Pavel (advisor) ; Holas, Ondřej (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Department of Pharmaceutical Technology Consultant: PharmDr. Pavel Ondrejček, Ph.D. Student: Lenka Bučková Title of Thesis: The influence of rice extract as a new lubricant on the compressibility of microcrystalline cellulose In this thesis the rice extract was studied as a new lubricant. Primarily its influence on microcrystalline cellulose compressibility was studied. Its effects were compared to sodium stearylfumarate and colloidal silicon dioxide. The used lubricants were wixed with the filler in the concentrations ranging from 0.1 to 1%. The mass flow rate was evaluated in the filler itself and its mixtures. Subsequently, the tablets were made using the compression forces ranging from 2.5 to 7.5kN. The compaction process was evaluated using the force- displacement method. Furthermore, the tablet hardness, friability and disintegration time was tested. The results showed that the rice extract can be used as lubricant for the used model filler. Unlike other evaluated glidants, it must be used at concentrations up to 0,25%. The use of higher concentrations does not improve the flow properties of tableting mixtures. In addition, material elasticity and tablet friability increases and tablet hardness decreases. On the other...
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Lubricants for metal sheet forming
Buchta, Ondřej ; Císařová, Michaela (referee) ; Štroner, Marek (advisor)
The subject of interest of this bachelor thesis is lubricants for sheet metal forming. The issues of friction are described in the thesis. The thesis presents an overview of the types of lubricants and their properties. An informative survey of selected available lubricants which are suitable for sheet metal.
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A study of the influence of lubricants on the ejection force of the tablets.
Novotná, Nikola ; Mužíková, Jitka (advisor) ; Ondrejček, Pavel (referee)
The aim of this study was to evaluate the effect of the type of lubricant, its concentration and mixing time with granules on the tablet hardness, ejection force and the lubrication index. Lactose was used as a filler in granules and polyvinylpyrolidone as a binder. Granules were prepared by wet granulation. Three types of talc were used in concentrations 1%, 3%, 5%, 7% a 10% and magnesium stearate in concetrations 1%, 2% a 3% as lubricants. Tablets were produced by tablet press DOTT Bonapace (model CPR-6) with the possibility to measure the force of the upper and lower punch and force-displacement. These values were used for the calculation of the lubrication index. The values of lubrication index were used for the lubricants comparison. The lubrication index with magnesium stearate did not change either with increasing concentration or with mixing time with granules. In case of each type of talc, the lubrication effect rose with increasing concentration but time of the mixing did not have any significant effect on the lubrication potential. Tablet strength decreased with higher lubricant concentration and longer mixing time when magnesium stearate was used. With increasing concentration of the lubricant tablet strength with talc first increased then stagnated or started to decrease. The higher...
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Suitable lubricants for deep drawing of stainless steel
Doležal, Jan ; Chudík, Ivan (referee) ; Lidmila, Zdeněk (advisor)
This thesis solves problems of design and construction of testing equipment for testing lubricants for deep drawing and experimental evaluation of suitability of different types of lubricants for specified tests conditions. Most of all it is about finding environmentally friendly lubricant which would provide similar results as lubricants containing chlorine compounds when drawing a stainless austenitic Cr-Ni steel 1.4301. As for lubricants provided for testing by leading home and abroad manufacturers, the ATLAS 3374-140 from Quaker Chemical and the WISURA ZW 3356 from FUCHS, were evaluated as the most suitable environmentally friendly lubricants.
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