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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
781

Planification de la récolte et allocation des produits aux usines

Gémieux, Géraldine 08 1900 (has links)
L’industrie forestière est un secteur qui, même s’il est en déclin, se trouve au cœur du débat sur la mondialisation et le développement durable. Pour de nombreux pays tels que le Canada, la Suède et le Chili, les objectifs sont de maintenir un secteur florissant sans nuire à l’environnement et en réalisant le caractère fini des ressources. Il devient important d’être compétitif et d’exploiter de manière efficace les territoires forestiers, de la récolte jusqu’à la fabrication des produits aux usines, en passant par le transport, dont les coûts augmentent rapidement. L’objectif de ce mémoire est de développer un modèle de planification tactique/opérationnelle qui permet d’ordonnancer les activités pour une année de récolte de façon à satisfaire les demandes des usines, sans perdre de vue le transport des quantités récoltées et la gestion des inventaires en usine. L’année se divise en 26 périodes de deux semaines. Nous cherchons à obtenir les horaires et l’affectation des équipes de récolte aux blocs de coupe pour une année. Le modèle mathématique développé est un problème linéaire mixte en nombres entiers dont la structure est basée sur chaque étape de la chaine d’approvisionnement forestière. Nous choisissons de le résoudre par une méthode exacte, le branch-and-bound. Nous avons pu évaluer combien la résolution directe de notre problème de planification était difficile pour les instances avec un grand nombre de périodes. Cependant l’approche des horizons roulants s’est avérée fructueuse. Grâce à elle en une journée, il est possible de planifier les activités de récolte des blocs pour l’année entière (26 périodes). / Forest industry is a sector located at the heart of the debate on globalisation and sustainable development, even if it is in decline. For many countries like Canada, Sweden and Chile, the objectives are to maintain a flourishing sector without damaging the environment and to realize the finite nature of resources. It is important to be competitive and to operate effectively on forest territories, from harvesting to manufacturing products, through transport, in a context where costs increase rapidly. This master’s thesis is developing a tactical operational planning model to organize activities for a year to meet requests for factories, without losing sight of the transport of harvested quantities and inventory management factory. The year is divided into 26 periods of two weeks. We seek harvest teams schedules and assignment to harvest areas (units) for a year. The problem is formulated as a mixed integer programming model, whose structure is based on each stage of the forest supply chain. We choose to solve it by an exact method, branch-and-bound. We were able to assess how the direct resolution of our planning problem was difficult for instances with a large number of periods. However the rolling horizon approach has proved successful. In a day, we obtained the harvest activities planning for 26 periods.
782

Development of a method for estimation of contact fatigue life in hypoid gears / Utveckling av en metod för att uppskatta livslängden för kontaktutmattning i hypoidväxlar

Vittal, Srigiripura Sahana January 2020 (has links)
Hypoid gears have been used extensively in automobiles, aerospace, marine and other applications for decades. The special advantages of hypoid gears come with inherent contact complexities of varying curvature and sliding in both profile and lengthwise direction. Spalling failure is catastrophic and needs to be addressed with deeper roots in gear design. Analytical methods present several limitations. Iterative development from experimentation is expensive and time consuming with different nonlinear parameters difficult to interpret. This thesis aims to develop a method to calculate contact fatigue life for initiation of spalling using finite element methods. Experiments have played a major role in understanding the causal factors for failure, determining the fatigue life and to study the major system design parameters. A failure analysis of the fractured flank is performed. It clarified the design causal factors for failure and the mechanism of failure. Pinion being the vulnerable part is the focus of this thesis, a finite element model was developed on ANSOL HFM and the residual stresses were superposed on MSC Marc. A finite element fatigue analysis is performed on FEMFAT and the component fatigue life is determined. The calculated fatigue life is compared with physical testing results using Weibull statistical analysis in combination with probabilistic bearing life models to formulate emphatical correlation methods. The goal of this thesis is to establish a method to estimate fatigue life by taking up example of computing subsurface fatigue life of a hypoid pinion. The influence factors like the method of contact analysis, different types of residual stresses due to case hardening and shot peening, fatigue criteria, friction, material properties are studied in this thesis to develop a conscience for the methodology to computing contact fatigue life. The bulk material properties based on hardness represented fatigue properties more accurately. Scaled normal stress in critical plane fatigue criteria was found more suitable for contact analysis with pre-stresses and multi-axial non-proportional contact stress state on FEMFAT. Finite element based contact analysis method was found to be more suitable for subsurface fatigue life estimation despite the inherent advantages of the hybrid surface integral method and its accurate representation of friction. It was found that inclusion of friction in model did not change the fatigue life significantly, showing that the influence of hardness, surface topographies lubrication and contact temperature on shear stresses are too large to be neglected. Contact fatigue life increased by a factor of 4.4 times due to shot peening of gears in comparison with case hardening indicating the influence of residual stresses. For the estimation of fatigue life at the initiation of failure, a complete correlation with the fatigue test results could not be achieved and reasons for deviations were clearly identified. The area of damage indicated by this computation method correlated with the damage observed during tests. The observations and calculations indicated premature failure of pinion with explanation of mechanism of failure of pinion flank using contact conditions. / Hypoidväxlar har använts i stor utsträckning i bilar, flyg-, marin- och andra applikationer under årtionden. De speciella fördelarna med hypoidväxlar kommer med inneboende kontaktkomplexitet med varierande krökning och glidning i både profil och längdriktning. Spallingfel är katastrofala och måste hanteras med grundlig redskapsdesign. Analytiska metoder har flera begränsningar. Iterativ utveckling baserad på experiment är dyrt och tidskrävande med olika icke-linjära parametrar som är svåra att tolka. Denna avhandling syftar till att utveckla en metod för att beräkna kontaktutmattningslivslängden för initiering av spalling med finitaelementmetoden. Experiment har spelat en viktig roll för att förstå orsaksfaktorerna för fel, bestämma utmattningslivslängden och för att studera de viktigaste systemdesignparametrarna. En felanalys av den skadade kuggflanken utfördes, vilket förtydligade felens orsaksfaktorer och den underliggande felmekanismerna. Driften är fokus för denna avhandling, en finitaelementmodell utvecklades med ANSOL-HFM och restspänningarna överlagrades med FEM-verktyget MSC-Marc. En slutlig elementutmattningsanalys utfördes med FEMFAT och komponentens utmattningstid bestämdes. Den beräknade utmattningslivslängden korrelerades med fysiska provningsresultat genom att tillämpa statistisk Weibullanalys i kombination med probabilistiska livslängdsmodeller. Målet med denna avhandling är att utveckla en metod för att uppskatta utmattningslivslängden och att tillämpa metoden för att beräkna bulkmaterialets utmattningslivslängd för ett hypoidrev. Påverkningsfaktorer som metoden för kontaktanalys, olika typer av restspänningar på grund av ythärdning och kulblästring, utmattningskriterier, friktion, materialegenskaper studeras i denna avhandling för att utveckla denna metod för att prediktera kontaktutmattningslivslängden. Bulkmaterialegenskaperna för hårdhet representerade utmattningsegenskaperna mera exakt. Skalad normalspänning i kritiska planutmattningskriterier befanns vara mer lämplig för kontaktanalys med förspänningar och multi-axiell icke-proportionell kontaktspänningsstatu än andra egenskaper med FEMFAT. Metodbaserad kontaktanalysmetod visade sig vara mer lämplig för uppskattning av ytutmattningslivslängd trots de inneboende fördelarna med hybridytaintegralmetoden och dess mera exakta friktionsrepresentation. Det visade sig att inkludering av friktion i modellen inte markant förändrade livslängden, vilket visade att påverkan av hårdhet, smörjning av ytorna och kontakttemperatur på skjuvspänningarna är för stor för att försummas. Kontaktutmattningslivslängden ökade med en faktor 4,4 gånger på grund av kugghjulning jämfört med ythärdning, vilket indikerar restspänningspåverkan. För att uppskatta utmattningslivslängden vid inledningen av ytfel kunde en fullständig korrelation med utmattningstestresultaten inte uppnås och orsakerna till avvikelser identifierades tydligt. Det skadade område som indikeras av denna beräkningsmetod korrelerade väl med den skada som observerades under testerna. Observationerna och beräkningarna indikerade tidigt fel i kuggen med förklaring av mekanismen för fel hos kuggflanken med hjälp av aktuellt kontaktförhållande.
783

Test Rig Adaptation for the Investigation of Bearings in Wave Energy Converters / Testriggsanpassning för undersökning av lager i Wave Energy Converters

Menon, Aju Sukumaran January 2021 (has links)
Wave ocean energy is a source of renewable energy which is gaining interest in the modern world. In contrast to other well-researched renewable energy sources such as wind energy, wave ocean energy is under the development phase. Governments around the world are encouraging the research of harnessing wave energy. As of now, there are different concepts to harness energy from waves. Tribological components are one of the main aspects that need attention in these wave energy converters. The moving components such as bearings can be the life-determining component of the entire device. This thesis provides conceptual solutions to adapt an existing start-stop bearing test rig to the conditions of wave energy converters. The test rig can test different bearing sused in the wave energy converters. The new design intends to provide scaled wave energy conditions. These conditions are mainly influenced by the oscillating movement of the bearings, the complex load condition and the salty environment. Since the testing of bearings in wave energy converters is in the initial stage, modular designs are implemented to test different types of bearings. / Se filen
784

Modeling and optimisation of a rotary kiln reactor for the processing of battery materials / Modellering och optimering av en roterugnreaktor för bearbetning av batterimaterial

Khawaja, Danial January 2021 (has links)
Roterugnar är cylindriska kärl som används för att höja materials temperaturer i en kontinuerlig process som kallas för kalcinering. Roterugnar kan tillämpas i olika processer såsom reduktion av oxidmalm samt återvinning av farligt avfall. Fördelen med roterugnar ligger i dess förmåga att hantera råmaterial som sträcker sig från slam till granulära material med en mängd olika partikelstorlekar, och därigenom upprätthålla distinkta miljöer såsom en bädd av fasta partiklar som samexisterar med ett oxiderande fribord. Sex olika bäddbeteende har dokumenterats med avseende på fyllningsgrad samt Froude nummer. Syftet med denna studie var att utveckla en tvådimensionell suspensions modell med CFD genom att använda den kommersiella mjukvaran COMSOL 5.5 för att simulera de två faser, gas och fast, som en blandad fas efter verk av Philips et. al., Physics of Fluids A: Fluid Dynamics 4.1 (1992) 30-40 och Acrivos & Zhang., International Journal Multiphase Flow 20.3 (1994) 579-591. Denna modell undersöktes genom att jämföra den med de dokumenterade flödesregimerna samt genom parameter som partikelstorlek, partikeldensitet och viskositeten hos gas i flödesregimen känd som rullande läge. Dessutom undersöktes temperaturprofilen för den roterande ugnen genom att utforska hur blandningsvariationer av den fasta bädden i den roterande ugnen påverkas av värmeöverföringen när värme tillförs från väggen under rullande läge. Resultaten av den tvådimensionella suspension modellen visade att det var bara möjligt att simulera glidläge korrekt; andra lägen kunde inte beskrivas som dokumenterat i litteraturen. Det indikeras att vilovinkeln och viskösa krafter i den roterande ugnen var låga vilket resulterade i att suspensions modellen inte kunde avbilda exakt de återstående flödesregimerna som dokumenterat. Till exempel avbildades rullningsläget mer likt forsandeläge då partiklarna fall fritt efter höjning av bädden. Partikelstorlek och partikeldensitet har visat sig ha en betydande påverkan på suspensions modellen eftersom de viskösa krafterna blir låga för en partikelstorlek och partikeldensitet under 0,4 mm respektive 1500 kg/m3. Angående gasens viskositet visades det sig att ju närmare värdet 2.055e-3 (Pa*s) den blev desto större blev sedimentationsflödet vilket resulterade i att bäddpartiklarna dras ner och förblir där. Suspensions modellen kunde således simulera en fast och flytande fas och inte en gasfas som avsett. Slutligen visade temperaturanalysen att påverkan av den termiska konduktiviteten var mer signifikant än den specifika värmekapaciteten i intervallet 1 - 50 (W/(m*K)) respektive 300 - 800 (J/(kg*K)) på grund av den tid det tog att nå en homogen temperaturprofil. / Rotary kilns are cylindrical vessels used to raise materials temperature in a continuous process known as calcination. Rotary kilns find application in various processes such as reduction of oxide ore and hazardous waste reclamation. The advantage of the rotary kiln lies in its ability to handle feedstock ranging from slurries to granular materials with a variety of particle size, thereby maintaining distinct environments such as a bed of solid particles coexisting with an oxidising freeboard. Six different bed behaviours within the kiln have been documented with respect to the filling degree and Froude number. The aim of this study was to develop a two-dimensional suspension model with CFD by using the commercial software COMSOL 5.5 to simulate the two phases, gas and solid, as a mixed phase, following the works of Philips et. al., Physics of Fluids A:  Fluid Dynamics 4.1 (1992) 30-40 and Acrivos & Zhang., International Journal Multiphase Flow 20.3 (1994) 579-591. This model was investigated by comparing it against the documented flow regimes as well as through parameters such as particle size, particle density and viscosity of gas in the flow regime known as rolling mode. In addition, the temperature profile of the rotary kiln was investigated by exploring how the mixture variation of the solid bed within the rotary kiln affects the heat transfer when heat is supplied from the wall during a rolling mode. The results of the two-dimensional suspension model showed that it was only possible to simulate the slipping mode accurately; others mode could not be described as documented in literature. It is indicated that the angle of repose and viscous forces within the rotary kiln were low resulting in the suspension model not being able to accurately depict the remaining flow regimes as documented. For instance, the rolling mode was depicted more as a cataracting mode due to the free fall of particles after elevation of the bed. The particle size and the particle density were found to have a significant impact on the suspension model as the viscous forces became low for a particle size and particle density below 0.4 mm and 1500 kg/m3 respectively. As for the viscosity of gas it was found that the closer it got to the value 2.055e-3 (Pa*s) the sedimentation flux became too large resulting in the bed particles being pulled down and remaining there. Thus, the suspension model could simulate a solid and liquid phase and not a gas phase as intended. Lastly, the temperature analysis revealed that the impact of the thermal conductivity was more significant than the specific heat capacity in the range of 1 - 50 (W/(m*K)) and 300 - 800 (J/(kg*K)) respectively, due to the time it took to reach a homogeneous temperature profile.
785

Linearization-Based Strategies for Optimal Scheduling of a Hydroelectric Power Plant Under Uncertainty / Linearization-Based Scheduling of Hydropower Systems

Tikk, Alexander January 2019 (has links)
This thesis examines the optimal scheduling of a hydroelectric power plant with cascaded reservoirs each with multiple generating units under uncertainty after testing three linearization methods. These linearization methods are Successive Linear Programming, Piecewise Linear Approximations, and a Hybrid of the two together. There are two goals of this work. The first goal of this work aims to replace the nonconvex mixed-integer nonlinear program (MINLP) with a computationally efficient linearized mixed-integer linear program (MILP) that will be capable of finding a high quality solution, preferably the global optimum. The second goal is to implement a stochastic approach on the linearized method in a pseudo-rolling horizon method which keeps the ending time step fixed. Overall, the Hybrid method proved to be a viable replacement and performs well in the pseudo-rolling horizon tests. / Thesis / Master of Applied Science (MASc)
786

Performance of Bearing rotor system under various operating conditions

Abbas Shafiee (18863803) 22 June 2024 (has links)
<p dir="ltr">Rolling element bearings (REBs) are common components in rotating equipment. They are used to carry loads and allow for rotation and misalignments with minimal friction. There exists a wide variety of ball and roller bearings that are suited for a wide variety of applications. All varieties of REBs operate with the same fundamental principles: force transferred from the shaft is applied to the inner race of a bearing, distributed among the rolling elements, and passed on through the outer race to the bearing housing. Load distribution among the rolling elements and the dynamic performance of the bearing is dependent on the bearing’s specifications and operating conditions. Bearing-housing and inner race-shaft fit classifications also control the bearing radial internal clearance (RIC), which eventually affects the bearing performance and load transferred to the housing.</p><p dir="ltr">This thesis experimentally and analytically investigates the load distribution and dynamic performance of rolling elements and investigates roller slip, tilt, and skew in a spherical roller bearing (SRB) under various combinations of loads and speeds. In order to have better insight into the effect of flexible housing and shaft on load distribution and dynamics of REBs, it was experimentally investigated the variation of inner race-shaft and outer race-housing interfaces on load and pressure maps at the bearing-housing interface for four different varieties of rolling element bearing: deep groove ball bearings, angular contact ball bearings, cylindrical roller bearings, and spherical roller bearings. Moreover, an integrated rotor-bearing housing system model developed to examine the behaviors of the rotor, bearing, and housing operating under various conditions.</p><p dir="ltr">In order to gain a deeper understanding of the dynamic behavior of REBs, a full six degree of freedom SRB dynamic model was developed in MSC ADAMS software. C++ based ADAMS/Solver subroutines, called dynamic bearing model (DBM), were developed and incorporated in ADAMS to compute reaction forces and moments in a rolling element bearing. DBM is based on the discrete element method (DEM), which assumes each of the bearing elements (i.e., rolling elements, cage, inner race, and outer race) to be a rigid body with six degrees-of freedom (DOF) in a three-dimensional space. A novel test rig (spherical roller bearing test rig, SRBTR) was also designed and developed to investigate load distribution and roller slip, tilt, and skew in an SRB. The test rig utilized a double-row SRB and was designed to allow for direct visual access to each row using a high-speed camera. The dynamic behavior of the rollers was corroborated with the developed analytical model. The experimental and analytical results indicate that the roller tilt angle increases with axial load, remains constant with speed, and decreases with increasing radial load when the roller is located in the load zone. Furthermore, roller skew in the load zone increases with axial load and shaft speed; however, it decreases with the radial load. The results indicate that when the radial-to-axial load ratio is greater than 4, roller tilt and skew are minimized. Due to roller intermittent slip and roller cage pocket collision in the unload zone, tilt and skew become unpredictable. The magnitude of the tilt and skew in the unload zone is directly related to the roller-race and roller-cage pocket clearances, respectively. Another test rig (pressure mapping test rig, PMTR) was designed to solely investigate how bearing-housing and inner race-shaft interfaces affect the load distribution in REBs. Thin film pressure sensors were utilized and placed around the perimeter of the test bearings inside of a housing to experimentally evaluate the pressure distribution between REBs and a housing under different loads and bearing-shaft and bearing-housing interfaces. Pressure map results were used to evaluate the effect of radial internal clearance on the load distribution of different bearing types. Pressure map results confirmed that the amplitude of load variation reduces with the bearing internal clearance. The thin film sensor system was also used to investigate the circumferential load distribution on the housing.</p><p dir="ltr">Previous ADAMS bearing models have assumed the bearing outer race to be fixed to the ground and the bearing inner race to be attached to a rigid shaft. In order to develop a more realistic and versatile bearing simulation tool, ADAMS bearing models were combined with flexible housings and rotor. To achieve an integrated rotor-bearing housing system model, the ADAMS bearing model was coupled through a set of interface points using component-mode-synthesis (CMS) for the rotor and housing model. The bearing outer races were discretized into multiple nodes to compute the force and deformation at the bearing housing conformal contact as well as to minimize the computational requirements associated with the conformal contact problems. The integrated model was then utilized to investigate the effects of rotor flexibility in the bearing rotor system and the effect of bearing clearance and housing clearance on bearing dynamics. It was demonstrated that the flexibility of the rotor has a significant effect on bearing element motion and dynamics. The results also indicated that depending on the bearing type, the shaft deflection can induce a moment within the bearing that is not readily identifiable from elementary theory. The results showed that the flexible housing undergoes deformations that create ovality in the bearing housing, thus affecting bearing dynamics. The model was also used to investigate bearing performance in a miniature wind turbine main shaft, utilizing a combination of SRB and cylindrical roller bearing (CRB) ADAMS models. Results suggest that the axial-to-radial load ratio should be less than the tangent of the SRB contact angle to avoid premature failure due to rollers sliding in the SRB as well as detrimental parallel misalignment in the CRB.</p>
787

Investigation of a thermomechanical process in a high temperature deformation simulator using an FE software : Using LS-DYNA to create a digital twin of the hot deformation simulator Gleeble-3800 GTC Hydrawedge module.

Tregulov, Farhad January 2024 (has links)
Thermomechanical processes such as hot rolling have been used in the industry for a long time to process and shape metals to a desired form with specific properties. However it can be difficult to make changes to the different process parameters. That's where it is beneficial to use a hot deformation simulator such as the Gleeble 3800-GTC. It can be used to test metals in a controlled environment where the deformation, temperature and other parameters are easily changed. When the machine uses a Hydrawedge module, it is able to simulate hot rolling using uniaxial compression at high temperatures. Swerim AB has one such machine and has requested to investigate what occurs inside a specimen during testing in the Gleeble, specifically inside two low-alloyed steels with a hardness between 400 and 500 HV. Such tests were replicated using LS-DYNA, an FE software. The goal was to acquire true stress-strain graphs that showed similar behaviour to the data from the Gleeble and plots of the effective plastic strain which could be correlated to the grain structure pattern inside the deformed cylinders. An FE-model was created which replicates the procedure. The model was verified through numerous steps. An initial mesh verification was done where the simulation time took at least 5 hours and at most 86 hours. Using a technique called mass scaling, the elements inside the model were manipulated using additional mass to increase their time step and reduce the computational time. A verification of the mass scaling was done where the computational time was weighed off against accuracy. Afterwards the friction had to be verified where it was found that the Gleeble test specimens were deformed more than necessary which was taken into account and the models were adjusted for friction verification. After all was said and done, the model had a reasonable friction coefficient with an optimal mesh and mass scaling configuration. The resulting model simulated a test of 0.5 seconds in 15 minutes and only costing at most 10 MPa in accuracy when experimental results have maximum values between 110 to 220 MPa depending on the scenario. This equals an approximate error of around 5-10%. When investigating the grain structure after 100 seconds of relaxation, the computational time amounted to 52 hours but could be reduced to 12 hours when simulating 30 seconds as there was no change in the effective plastic strain after that time. The final model has a high enough accuracy which, when combined with the Gleeble, is able to confirm material models and describe what occurs in the material during conditions akin to hot rolling.
788

Имитационная модель приводного механизма рабочей клети стана ХПТ-90 : магистерская диссертация / Simulation model of the drive mechanism of the working stand of a cold pipe rolling mill (ХПТ-90)

Шапоренко, А. О., Shaporenko, A. O. January 2024 (has links)
В данной работе изучено общее строение станов ХПТ и в частности строение приводного механизма. На основе этих данных созданы модели деталей привода в системе трехмерного моделирования КОМПАС-3D. В программе Mathcad рассчитаны данные переходных процессов пуска двигателя, а в программе для моделирования систем Simulink смоделирован двигатель. Далее в среде для имитационного моделирования многозвенных трёхмерных механических систем Simscape Multibody собрана блок-схема приводного механизма рабочей клети стана ХПТ, к ней подключён электродвигатель. В результате исследования была получена имитационная модель приводного механизма рабочей клети стана ХПТ-90, проведена симуляция и исследование её работы. Данная модель позволяет: наглядно продемонстрировать работу механизма; обнаружить ошибки в работе; определить оптимальные параметры прокатки; оптимизировать процессы; снизить стоимость испытаний механизма; снизить затраты времени при проектировании. / In this work, the general structure of cold pipe rolling mills and, in particular, the structure of the drive mechanism were studied. Based on these data, models of drive parts were created in the KOMPAS-3D three-dimensional modeling system. The motor starting transient data was calculated using Mathcad, and the motor was simulated using the systems modeling software Simulink. Next, in the simulation environment for multi-link three-dimensional mechanical systems Simscape Multibody, a block diagram of the drive mechanism of the working stand of a cold pipe rolling mill was assembled, and an electric motor was connected to it. As a result of the study, a simulation model of the drive mechanism of the working stand of the cold pipe rolling mill (ХПТ-90) was obtained, a simulation and study of its operation was carried out. This model allows you to: clearly demonstrate the operation of the mechanism; detect errors in operation; determine optimal rolling parameters; optimize processes; reduce the cost of testing the mechanism; reduce time spent on design.
789

Исследование энергосиловых условий винтовой прошивки заготовок при производстве труб : магистерская диссертация / Investigation of screw piercing energy-force conditions for pipe manufacturing process blanks

Першин, О. В., Pershin, O. V. January 2024 (has links)
Объектом исследования являлись двухвалковые прошивные станы, входящие в технологическую линию трубопрокатных агрегатов ТПА-140 АО «Челябинский трубопрокатный завод» («ЧТПЗ») и АО «Синарский трубный завод» (СинТЗ»). Цель работы – исследование энергосиловых условий винтовой прошивки при производстве труб различного типоразмера из различных марок стали на прошивных станах ТПА-140. Предметом исследования являлись энергосиловые условия, возникающие в главной линии станов (приводе валков) при прошивке наиболее распространенных типоразмеров труб на данных станах. Методом исследования является комплексный экспериментально-теоретический анализ данных, полученных в ходе промышленных экспериментов, при производстве горячекатаных труб в заводских условиях. В работе представлена методика экспериментального исследования энергосиловых условий винтовой прошивки, приведено описание применяемых средств, методов сбора и анализа полученных данных. В результате были сформулированы рекомендации по уровням энергосиловых условий нагрузки прошивных станов ТПА 140 и по энергосбережению при прошивке, предложен способ регулировки уровня токовых нагрузок при прошивке. Результаты работы могут быть использованы непосредственно на производстве, на станах, имеющих подобную конструкцию и используемых для обработки труб из схожих сталей и сплавов, аналогичного сортамента. / The research object was two-roll piercing mills included in the pipe rolling units “TRA-140” technological line of JSC “Chelyabinsk Tube Rolling Plant” (“ChTPZ”) and JSC “Sinarsky Pipe Plant” (“SinTZ”). The objective of the work was to investigate the energy and force conditions of screw piercing during the different sizes pipes production from different steel grades on piercing mills "TPA-140". The research subject was the energy force conditions occurring in the roll line of the mills (roll drive) during piercing of the most common pipe sizes at these mills. The method of research is a complex experimental-theoretical analysis of data obtained during industrial experiments in the hot-rolled pipes production in factory conditions. The investigation illustrates the methodology of experimental research of the screw piercing energy-force conditions, provides a description of the applied instruments, collecting methods and obtained data analyzing. As a result of the work, recommendations for the levels of energy force conditions in the load of piercing mills “TRA 140” were formulated, as well as recommendations for energy saving in the piercing process, and a method for adjusting the current loads level in the piercing process was proposed. The obtained results of the work can be used directly in manufacturing, on the mills having similar design and used for pipes treatment made of similar steels and alloys, and of similar assortment.
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Lucifer och den performativa filmkonsten : En studie kring sataniska visioner i den kaliforniska filmvärlden

Ljung, Peter January 2019 (has links)
This study regards the influence of ’modern’ satanism on performative art in the nineteen sixties- and seventies. The methodological framework consists of performativity theory, religious visual culture and aesthetics of experimental film. The material consists mainly of cinematic work by Kenneth Anger and Alejandro Jodorowsky, as well as musical performances by the likes of Mick Jagger, the Rolling Stones and David Bowie. In addition to this material I also use academic texts, dissertations and books written about the subjects themselves as a foundation for my own further analysis and discussions. By looking closely at a selection of cinnematic work of foremost Kenneth Anger, I try to show how his own esoteric and occult interests are present as a fundamental part of his creative process and the following filmworks/artworks themselves. This is also put into relationship with Anton Szandor Lavey, founder of the Church of Satan, and their common thoughts concerning ritually performed magic. By using performativity theory I trie to emphasise the interlocking structures of these two worlds in the artwork of Kenneth Anger and other artists active in the culturual ’milieu’ of the sixties- and seventies. The results indicate that the religious sphere of satanism, occultism and esotericism (and alternative modes of religion in general) was closeley inflicted with counterculture-infused film and music (as represented by the selection of material).

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