Spelling suggestions: "subject:"excavation"" "subject:"excavated""
51 |
Analýza namáhání vybraných konstrukčních částí bagru při provozu / Analysis of mechanical loads of selected structural parts of the excavator during operationBusta, Michal January 2021 (has links)
This thesis is focused on the issue of computational modeling of soil harvesting while using the compact excavator from the company DOOSAN BOBCAT EMEA s.r.o.. The solution consists in creating two computational models in Rocky DEM and Ansys Mechanical. Rocky DEM software is used to solve the disconnection of soil by excavator components using the discrete element method. The outcome includes courses of forces and moments during the particular time of the individual joints of the model that was used. The obtained courses are then applied as an external load to the joint of a selected structural part of the analyzed model using a kinematic model in ANSYS Mechanical. The kinematic model consists of simplified geometry models of individual parts of the excavator arm, and a more detailed geometry model of the analyzed part of the arm. All the parts are connected to each other by rotational bonds representing joints. A static structural analysis of the mechanical stress is performed in ANSYS Mechanical for the prepared model during the simulated process. Finally, the selected structural part is assessed with respect to the elastic limit and fatigue strength.
|
52 |
Manipulátor velkorypadla KK1300 / Manipulator of bucket wheel excavator KK1300Adamík, Jan January 2010 (has links)
The document describes a manipulator for a wheel excavator. The purpose of the manipulator is to handle with the propulsive shaft of a crushing machine and the tension cylinder of an interchanging conveyor-belt during the assembling and maintenance. The objective of the master's thesis is the strength analysis of the manipulator components and the telescopic arm with using the finite element method. The thesis also comprises the assembly drawing of the manipulator with additional devices and the propulsion system calculation. The project is carried out with the cooperation of NOEN a.s.
|
53 |
Beranidlo pro rážení hloubkových trnů / Drop hammer for driving spindleSvatoš, Ivo January 2011 (has links)
Thesis deal with design of drop-hammer and especially its carriage (frame) for direction equipment for driving various thin-walled profiles in civil engineering. The entire drop- hammer is used as an additional adapter for construction machine. The first part of thesis contains design options, description of chosen option, including principles of work with drop- hammer. It also contains the calculation which are important for design of parts of drop- hammer, frame strese analysis by computer software, the approximate production coast of drop-hammer and summary of the parameters of the final product. The annexes contains the specified drawings and examples of 3D models of assemblies.
|
54 |
Pevnostní analýza a optimalizace kabiny dvoucestného rypadla MH Plus S / Strength analysis and optimization of the two-way excavator MH Plus S cabZavadil, Milan January 2013 (has links)
This diploma thesis deals with stress analysis and optimization of two-way cab excavator MH Plus S with total weight of machine 19375 kg. Stress analysis has been performed using the finite element method (FEM). As next step the structure design of protective frame and strength analysis of the cab and protective frame, which protect crew when the machine is rolled over protective structure (ROPS) according to ČSN EN ISO 3471 standard, have been made. The design documentation is a part of diploma thesis. This diploma thesis was conducted in cooperation with the firm Agrotec a.s.
|
55 |
Challenges and possibilities of the integration of electric drives in mobile machineryOpgenoorth, Andreas, Quabeck, Stefan, De Doncker, Rik W., Schmitz, Katharina 25 June 2020 (has links)
This paper provides an overview of the challenges and possibilities of the integration of electric drives into diesel-hydraulic excavators. Due to the drivers of emission reduction, the use of renewable energies and more energy efficient systems, a global push leads to the integration of electric drives in excavators. In mobile machinery such as excavators, new possibilities and challenges of the adaptation of the drive train and energy storage arise. Rotational actuators can be powered by direct electric drives to avoid losses of the hydraulic system. Adapted hydraulic system topologies enable recuperation and reduce throttling losses in hydraulic systems. Variable and overall higher electric motor speeds reduce the size of the electric and hydraulic components and enable operation in more efficient operating points. To evaluate possible changes to the traditional hydraulic excavator systems, a simulation model is built and the proposed adaptations are implemented. The paper concludes with the evaluation of the proposed system changes and an outlook for further possibilities of hydraulic system adaptions in relation to the electric drive.
|
56 |
Applying a multi-service digital displacement® pump to an excavator to reduce valve lossesPellegri, Matteo, Green, Matthew, Macpherson, Jill, McKay, Callan, Caldwell, Niall 25 June 2020 (has links)
Reducing the energy consumption of off-highway machinery due to poor system efficiency is an urgent challenge. Several advanced and innovative architectures have been proposed over the years to tackle this problem, but very few of them found fertile ground for commercial applications due to increased complexity and cost. In this paper, the design, implementation, and testing of a multi-service Digital Displacement ® Pump architecture applied to an excavator are presented. The Digital Displacement ® Pump allows for a dynamic physical displacement allocation to services at different pressure levels, thus reducing throttling losses required to operate multiple actuators simultaneously. A feed-forward control logic is implemented and applied to the system using a closed-centre architecture. The results indicate a fuel reduction of more than 30% compared to the baseline excavator.
|
57 |
シミュレーションによる油圧ショベルの自動化に関する研究 / シミュレーション ニヨル ユアツ ショベル ノ ジドウカ ニカンスル ケンキュウ吉田 達哉, Tatsuya Yoshida 22 March 2014 (has links)
本研究では油圧ショベルの生産性の向上のための掘削制御方策の確立をシミュレーションモデルによって行い,その有効性の検証を行うことを目的とした.個別要素法を用いて土壌を離散的に解析することで,掘削の生産性を評価できるモデルを構築した.さらに油圧ショベルの動力学モデルを構築することで掘削作業を行うために必要なエネルギを解析する.この2つモデルを組み合わせ,掘削に必要なエネルギあたりの掘削量を生産性の指標として,生産性の定量的評価を行う. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
|
58 |
A prologue to the post coal-mining eraJonas, Lisa January 2019 (has links)
The surface mine Hambach is located in the west of Germany, close to Cologne and was founded in 1978 from the electric company RWE to dig up brown coal and produce electricity. The mine measures a surface of 8.500ha and a depth of 470 m and was planned to be operated until 2045. After mining RWE plans to recultivate the area with forest, agriculture and a remaining lake of 3900ha. The mine is a site that is out of proportion. This proposal is a composition of interventions in different time and scale aiming to tell the story of soil, water, vegetation, animals and humans. The excavator is a scale figure to these dimensions and becomes the protagonist of the story. On it‘s way down to its final position at the bottom of the pit, it is sculpting the soil one last time. After that last operation nature will take over. Water will find its path and reshape the pattern of the excavator. With water, vegetation comes back and then gives space for animals to live and humans to watch the transition from a colourful desert to a flourishing oasis. This stream of interventions is connecting the pit‘s terraces to a spiral sculpture that over time will fill with water.
|
59 |
Utveckling av en skopkonstruktion med lägre produktionskostnader / Development of a bucket design with lower production costsHamid Elamin, Hamed, Mohammad Taher, Handrin January 2015 (has links)
Detta examensarbete handlar om en skopkonstruktions utveckling, avsedd för en serieskopor men konstruktionen har enbart implementerats på en kabelskopa. Arbetet har utförtspå uppdrag av ett verkstadsföretag som utvecklar, tillverkar och säljer entreprenadutrustningtill grävmaskiner och hjullastare. Företagets vision är att komma ut på den svenskalågprismarknaden, men i dagsläget är produktionskostnaderna på skoporna för höga. Måletmed arbetet har varit att ta fram en konstruktionslösning som sänker företagets produktionskostnader.Efter ett möte med företaget tydliggjordes vilka behov som efterfrågades och dessa behovtolkades i form av kundkrav. Med en QFD-analys översattes kundkraven till produktegenskapersom krävs för en lyckad skopkonstruktion. Fokus har främst lagts på att förenklaskopans montering och anpassa dess konstruktion för robotsvetsning. Några faktorer harvarit att utforma självfixerande detaljer och beakta åtkomlighet för svetsning. Konceptengenererades genom intern och extern sökning, där metoder så som brainstorming och konkurrentanalyshar använts.Konceptvalet utfördes med Pughs beslutsmatris, där ett relativt optimalt koncept valdes förfortsatt utveckling. Vid utvecklingen har diverse verifieringsmetoder använts, som till exempelriskanalys, finita elementmetoden (FEM) och kostnadskalkyl för att kontrollera attdet valda konceptet uppfyller de uppsatta kraven för skopan. I verifieringsfasen identifieradesflera förbättringsmöjligheter som implementerades på det valda konceptet och dettagav ett bättre koncept än tidigare.Det slutliga konceptet har fått en sänkt produktionskostnad, med effektivare montering,minskad materialanvändning och svetsning samt en bättre prestanda än tidigare. / This thesis is about the development of a bucket design; intended for a range of excavatorbuckets consisting of four different types, but has only been implemented on the cablebucket. The work has been performed on behalf of a company that develops, produces andsells construction equipment for excavators and wheel loaders. At the present, the company'sexcavator buckets have high production costs, but the vision is to get into the low-costmarket. The goal of this work has been to develop a bucket design that reduces the company'sproduction costs.After a meeting with the company it became clear what needed to be achieved. The collectedneeds were interpreted in terms of customer requirements. A QFD was made, and thecustomer requirements were translated into product specifications for a successful bucketdesign. Particular focus has been put on simplifying the assembly of the bucket and adaptingits design for robot welding. Some essential factors have been to design interactingparts and to consider the accessibility for welding. The concepts were generated throughinternal and external searches, where methods as brainstorming and competitor analysiswere used.Concept selection was made by using Pugh's decision-matrix. A relatively optimal conceptwas selected for further development. During the development, various verification methodswere used, as for example risk analysis, finite element analysis (FEA) and cost estimate,to verify that the selected concept meets the set requirements for the excavator bucket.Several potential improvements were identified during the verifications phase and theseimprovements were implemented on the selected concept, which resulted in an even betterconcept than before.The final concept obtained a reduced production cost, with a more efficient assembly, reducedmaterial use and welding as well as a better performance than before.
|
60 |
Archéologie et éducation au patrimoine culturel : le sacré et le profane dans un chantier de fouilles archéologiques : Entretiens avec quatre bénévoles / Archaeology and cultural heritage education : the sacred and the profane in an Archeologiques : entretiens with four excavation site VolunteersLasheb, Ramdane 19 February 2019 (has links)
Dans cette étude, nous proposons une autre voie d’éducation au patrimoine culturel, celle qui s’effectue à travers les fouilles archéologiques pour bénévoles (espace sacré et espace profane).Nous explorons d’abord le contexte dans lequel elle se réalise. Ensuite, nous nous intéressons aux éléments théoriques conceptuels relatifs aux « apprentissages expérientiels » et au « sacré/profane ». En s’appuyant sur l’analyse de contenu de quatre entretiens semi-directifs, nous tentons dans un premier temps, d’identifier les apprentissages techniques (prospections, techniques de fouilles…) et socio-culturels (valeurs universelles) qu’acquièrent les bénévoles de l’archéologie dans l’expérience des fouilles. Dans un deuxième temps, nous nous attelons à montrer que la confrontation au sacré et au profane induit chez les bénévoles, un changement, une « trans-formation » et une évolution vers l’universel des représentations. Enfin, nous nous attachons à révéler l’impact des apprentissages en évoquant l’implication des fouilleurs dans la protection et la sauvegarde du patrimoine culturel. Cette étude souligne donc que l’éducation au patrimoine culturel à travers l’expérience des fouilles archéologiques passe à la fois par la confrontation au sacré et profane et par le retour réflexif sur l’expérience personnelle de ces bénévoles. / In this study, the author proposes an alternative education to a cultural heritage, which is carried out through archaeological excavations from volunteers (sacred space and profane space). He first explores the context in which to realize it. Then, he is interested in the conceptual theoretical aspects "experiential learning" and the "sacred/profane." Relying on the content analysis of four in-depth interviews, the author tries in a first step, identify technical learning (surveys, excavations... technical) and socio-cultural (universal values) gain volunteers of Archaeology in the experience of the excavations. In a second time, he is working to show the confrontation to the sacred and the profane induced in volunteers, a change, a transformation and evolution towards universality of the representations. Finally, it strives to show the impact of learning by referring to the involvement of hunters in the protection and conservation of cultural heritage. This study aims to show that education to cultural heritage through the experience of archaeological excavations goes on both by the confrontation to the sacred and profane and reflexive return on the personal experience of the volunteer excavators.
|
Page generated in 0.0423 seconds