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1
Åkerlund, Elin, Rebecka Havo, Åberg Jakob Jonsson, Patrik Österberg, and Mikael Fredriksson. "High Performance Steel for Percussive Drilling." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323387.
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Atlas Copco Secoroc AB are searching after new bulk materials for drill heads that are used in percussive drilling in order to improve their strength and durability. The aim of this project is to assist Atlas Copco in this search and provide them with further information regarding material properties, alloying elements, suppliers, etc. A literary study was carried out in order to identify materials that had UTS and KIC more than or equal to 1700 MPa and 70 MPa*m1/2, respectively. Materials that fulfilled these criteria were T250 grade maraging steel, Cobalt free maraging steel, High cobalt maraging steel, 300 grade maraging steel, AerMet 100, AF1410, S53, M54, 300M, 4340M and PremoMet. These were categorized into maraging steels, high alloy secondary hardened steels, and low alloy steels, and were then further researched. The material with the highest combination of UTS and KIC was M54 followed by AerMet 100; while AF1410 had the highest KIC but a low UTS, and PremoMet had the highest UTS but a low KIC. Maraging steels and HASH steels have a similar price range, while low alloy steels are much cheaper.
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Åkerlund, Elin, Åberg Jakob Jonsson, Patrik Österberg, Rebecka Havo, and Mikael Fredriksson. "High Performance Steel for Percussive Drilling." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323808.
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Atlas Copco Secoroc AB are searching after new bulk materials for drill heads that are used in percussive drilling in order to improve their strength and durability. The aim of this project is to assist Atlas Copco in this search and provide them with further information regarding material properties, alloying elements, suppliers, etc. A literary study was carried out in order to identify materials that had UTS and KIC more than or equal to 1700 MPa and 70 MPa*m^1/2, respectively. Materials that fulfilled these criteria were T250 grade maraging steel, Cobalt free maraging steel, High cobalt maraging steel, 300 grade maraging steel, AerMet 100, AF1410, S53, M54, 300M, 4340M and PremoMet. These were categorized into maraging steels, high alloy secondary hardened steels, and low alloy steels, and were then further researched. The material with the highest combination of UTS and KIC was M54 followed by AerMet 100; while AF1410 had the highest KIC but a low UTS, and PremoMet had the highest UTS but a low KIC. Maraging steels and HASH steels have a similar price range, while low alloy steels are much cheaper.
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Volec, Martin. "Malá vrtná souprava pro vrtání studní." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232188.
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The aim of this thesis is the structural design small drilling rigs for drilling wells. Drilling rig will be used for drilling wells up to 200 mm diameter rotary drilling technology with irrigation water. The first part is a literature search of small drilling rigs. In the second part, then custom design a small drilling rig.
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Davidson, Sean R. H. "Heat transfer in bone during drilling." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/MQ46070.pdf.
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Maštera, Lukáš. "Koncepce vysokorychlostní vrtné hlavy pro odběr vzorků hornin." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443237.
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THE THESIS FOCUSES ON A CONSTRUCTION DESIGN OF A NEW DRILLING HEAD DESIGNED TO REPLACE THE ORIGINAL ONE IN A MULTIDRILL HYNDAGA DRILLING RING. THE SUBSTITUTION IS SUPPOSED TO PROVIDE A SOLUTION TO THE SHORTCOMINGS OF THE CURRENTLY USED DRILLING HEAD. THE THESIS ANALYSES PARAMETERS OBTAINED FROM THE MANUFACTURER, NEW PRODUCTION REQUIREMENTS AND PROPOSES TWO TYPES OF MOTORS INNOVATIVE METHODS HAD BEEN IMPLEMENTED IN CALCULATIONS OF CONCEPTUAL PARAMETERS OF THE NECESSARY COMPONENTS. THE OUTCOME IS A NEW F-TYPE DRILLING HEAD.
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Leden, Pavel. "Výroba tělesa pro klíčový zámek." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229935.
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The diploma thesis is focused on the production of body for cylinder locks. This is production of very small and accurate parts. In the first part there is described the function of the lock, the sort of cylinder locks, their components and the basic types of safety elements. The second part is focused on the production of given type of body. The thesis deals with either existing production technology or proposals of possible innovation. This firstly consists in new organization of manufacturing operations. At the close we can find comparison of existing technology and new proposal.
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Apak, Esat Can. "A Study On Heat Transfer Iside The Wellbore During Drilling Operations." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608048/index.pdf.
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Analysis of the drilling fluid temperature in a circulating well is the main objective of this study. Initially, an analytical temperature distribution model, which utilizes basic energy conservation principle, is presented for this purpose. A computer program is written in order to easily implement this model to different cases. Variables that have significant effect on temperature profile are observed. Since the verification of the analytical model is not probable for many cases, a computer program (ANSYS) that uses finite element method is employed to simulate different well conditions. Three different wells were modeled by using rectangular FLOTRAN CFD element that has four nodes. Maximum drilling fluid temperature data corresponding to significant variables is collectedfrom these models. This data is then used to develop an empirical correlation in order to determine maximum drilling fluid temperature. The proposed empirical correlation can estimate the temperature distribution within the wellbore with an average error of less than 16%, and maximum drilling fluid temperature with an average error of less than 7 %.
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Jin, Kenichiro 1979. "Thermal analysis of directional drilling tool in high heat flux environment." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/89354.
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Maani, Nazanin. "A MODEL FOR THE PREDICTION OF THERMAL RESPONSE OF BONE IN SURGICAL DRILLING." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1245.
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This Thesis develops a mathematical model for predicting the thermal response in the surgical drilling of bone. The model accounts for the bone, chip and drill bit interactions by providing a detailed account of events within a cylindrical control volume enveloping the drill, the cut bone chip within the drill bit flute and the solid bone. Lumped parameter approach divides the control volume into a number of cells and cells within the sub-volumes representing the drill solid, the bone chip and the bone solid are allowed to interact. The contact mechanics of rough surfaces is used to model chip-flute and chip-bone frictional interaction. In this way not only the quantification of friction due to sliding contact of chip-flute and chip-bone rough surface contact are treated, but also the contact thermal resistances between the rubbing surfaces are included in the model. A mixed combination of constant and adaptive mesh is employed to permit the simulation of the heat transfer as the drill bit penetrates deeper into the bone during a drilling process. Using the model the effect of various parameters on the temperature rise in bone, drill and the chip are investigated. It is found that maximum temperature within the bone occurs at the location adjacent to the corner of the drill-tip and drill body. The results of the model are found to agree favorably with the experimental measurements reported in the existing literature on surgical drilling.
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Santoyo-Gutierrez, Edgar Rolando. "Transient numerical simulation of heat transfer processes during drilling of geothermal wells." Thesis, University of Salford, 1997. http://usir.salford.ac.uk/14689/.
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The transient thermal history of a well drilling system has been identified as one of the main problems that the geothermal well drilling industry needs to solve. In particular, the estimation of temperatures, in and around a geothermal well during drilling (circulation) and shut-in (thermal recovery) conditions, is required. To overcome this problem, a computer simulator (WELLTHER) has been developed which uses a direct solution method to solve the finite difference equations describing the transient heat transfer processes in a wellbore during drilling and shut-in operations in the presence of the lost circulation to the formation. The new computer simulator uses a numerical model to account for the transient convective heat transfer in the formation surrounding a well, due to lost circulation. This feature of the present simulator is important, since previous wellbore simulators consider the heat transfer process in the formation (rock) as a merely conductive problem. The WELLTHER simulator is capable of accounting for these losses at any point in the well and it has been applied to the study of several Mexican geothermal wells. The results show that the effect of lost circulation on the shut-in temperature profiles can be reproduced satisfactorily. Likewise, a parametric analysis, carried out using the simulator, indicates that a number of assumptions made in previous numerical models are invalid and that certain factors ignored in previous models have a significant effect on the dynamic wellbore temperature distribution. Finally, a coupling of the new simulator with another computer code (STATIC TEMP) can be used as a tool to infer more reliably the static formation temperatures in geothermal systems.
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Mishra, Brijes. "Analysis of cutting parameters and heat generation on bits of a continuous miner using numerical and experimental approach /." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5514.
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Thesis (Ph. D.)--West Virginia University, 2007.Title from document title page. Document formatted into pages; contains ix, 104 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 94-96).
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Branscome, Ewell Caleb. "A Multidisciplinary Approach to the Identification and Evaluation of Novel Concepts for Deeply Buried Hardened Target Defeat." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14092.
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The objective of the work described was to identify and explore a paradigm shifting solution that could offer leap-ahead capabilities to counter current and future DBHT threats while mitigating or eliminating the self-deterrence issue. A multidisciplinary approach to the problem was formulated and implemented. Systematic evaluation of DHBT defeat alternatives lead to the selection of a thermal subterrene as a hypothetical means of providing such a capability. A number of possible implementation alternatives for a thermal subterrene were investigated, resulting in the identification of the RadioIsotope Powered Thermal Penetrator (RIPTP) concept for providing an effectively unlimited, self-contained hard rock penetration capability using near-term technologies. However, the proposed approach was novel and thus required formulation and application of a physics based multidisciplinary analysis code to enable evaluation of design alternatives and analysis of performance. The following disciplinary analyses were composed into a multidisciplinary analysis code for a RIPTP: packing of RIPTP components in available volume; close-contact melting analysis; transmutation of isotope species by neutron activation; reactor neutron economy; radioisotope power generation through decay; metamodelled radiation shielding calculations for a RIPTP; and steady state thermal analyses for a RIPTP in various scenarios. Performance analysis of the identified baseline Thulium-170 RIPTP suggested that the predicted low penetration rate of about 10 meters/day could be a significant negative factor with regards to possible viability of the concept. Consequently, a survey for potentially enabling technologies was performed using an adaptation of the Technology Impact Forecasting (TIF) approach. It was found that the greatest potential for improving performance of the baseline Thulium-170 RIPTP resulted from increasing overall power density of the penetrator. Several possible technology approaches to achieving significantly increased penetration rates are proposed.
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Béjar, Luis Miguel. "CORROSION-FATIGUE TESTING ON STEEL GRADES WITH DIFFERENT HEAT AND SURFACE TREATMENTS USED IN ROCK-DRILLING APPLICATIONS." Thesis, KTH, Materialvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-194524.
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Corrosion fatigue is a common failure mechanism in rock drilling components and many othermechanical parts subjected to cyclic loads in corrosive environments. A crucial part in the design ofsuch components resides in the selection of the right materials for the application, which ideallyinvolves testing and comparison of their performance under working conditions. The present work was performed with the purpose of designing a corrosion-fatigue testing methodthat would allow the designer to compare the performance of different materials exposed to corrosionfatigue, permitting also the comparison with results from dry fatigue testing. The method was designedfor rotating-bending machines. Two different steel grades were used during the work, one throughhardened and one case hardened. The effect of these heat treatments and of shot peening overcorrosion-fatigue behaviour were studied using the proposed method. It was proven that the testing speed has a strong impact on the fatigue life of steel. It was found that,at a fixed stress level, the case hardened and shot peened steel reached 3X10^6 cycles at 2300 rpm,while it failed at only 5X10^5 cycles with a testing speed of 500 rpm. A large beneficial influence of theshot peening was demonstrated. It was also observed that, at fixed testing speed, the shot peening onthe through hardened steel can increase its fatigue strength from 190 MPa to 600 MPa under corrosionfatigue. Many cracks were found at the surface of the shot peened parts, which are arrested near thesurface by the compressive stress layer from the shot peening. It was also found that, for the non-shotpeened parts, case hardening had a slightly higher corrosion-fatigue strength than the throughhardened. This might be a result of the compressive stresses from carburization, or due to the highercore toughness of this steel grade.
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Kalidindi, Varahalaraju. "OPTIMIZATION OF DRILL DESIGN AND COOLANT SYSTEMS DURING DENTAL IMPLANT SURGERY." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/314.
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Dental implants are an effective alternative for the replacement of missing teeth. The success of the implant depends on how well a bone heals around the implant, a process known as osseointegration. However, excessive heat generated during the bone drilling will cause cell death and may prevent osseointegration of the implant, resulting in early failure. There are many factors which contribute to the heat generation during drilling. Experiments were carried out to investigate the affect of variable drilling factors on heat generation during drilling operation. Natural bone is not an ideal material for such research, as it varies widely in density and other parameters of interest.. It would be desirable to have a more uniform and consistent material to use in such studies. However, such a material must be similar to bone to allow the results to be extrapolated to the clinical situation. The current study describes and validates a model for use in such studies. Polymethylmethacrylate (PMMA) is the material chosen for our studies. A theoretical model was developed to study the effect of different drilling parameters on temperature rise during drilling operations. Comparison of observed results obtained from experiments was made with the results from theoretical study. Comparison of results for PMMA and human bone are also shown explaining how PMMA material can be substituted for human bone. The results suggest that the PMMA model is an acceptable surrogate for bone in such studies.
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Kolandaivelu, Kannikha Parameswari. "Hydrothermal Transport in the Panama Basin and in Brothers Volcano using Heat Flow, Scientific Deep Sea Drilling and Mathematical Models." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/99631.
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Two-thirds of submarine volcanism in the Earth's ocean basins is manifested along mid-ocean ridges and the remaining one-third is revealed along intraoceanic arcs and seamounts. Hydrothermal systems and the circulation patterns associated with these volcanic settings remove heat from the solid Earth into the deep ocean. Hydrothermal circulation continues to remove and redistribute heat in the crust as it ages. The heat and mass fluxes added to the deep ocean influence mixing in the abyssal ocean thereby affecting global thermohaline circulation. In addition to removing heat, hydrothermal processes extract chemical components from the oceanic and carry it to the surface of the ocean floor, while also removing certain elements from seawater. The resulting geochemical cycling has ramifications on the localized mineral deposits and also the biota that utilize these chemical fluxes as nutrients. In this dissertation, I analyze observed conductive heat flow measurements in the Panama Basin and borehole thermal measurements in Brothers Volcano and use mathematical models to estimate advective heat and mass fluxes, and crustal permeability. In the first manuscript, I use a well-mixed aquifer model to explain the heat transport in a sediment pond in the inactive part of the Ecuador Fracture Zone. This model yields mass fluxes and permeabilities similar to estimates at young upper oceanic crust suggesting vigorous convection beneath the sediment layer. In the second manuscript, I analyze the conductive heat flow measurements made in oceanic between 1.5 and 5.7 Ma on the southern flank of the Costa Rica Rift. These data show a mean conductive heat deficit of 70%, and this deficit is explained by various hydrothermal advective transport mechanisms, including outcrop to outcrop circulation, transport through faults, and redistribution of heat by flow of hydrothermal fluids in the basement. In the third manuscript, I analyze the borehole temperature logs for two sites representative of recharge and discharge areas of hydrothermal systems in the Brothers Volcano. I develop upflow and downflow models for fluids in the borehole and formation resulting in estimated of flow rates and permeabilities. All three independent research works are connected by the common thread of utilizing relatively simple mathematical concepts to get new insights into hydrothermal processes in oceanic crust.PHD
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Chen, Sebastian, and Disa Fredriksson. "Utvärdering av löstoppsborrars prestanda : Som ett led i Scanias standardiseringsarbete ienlighet med SPS." Thesis, KTH, Industriell produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232576.
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Inom tillverkning är skärande bearbetning en vanligt förekommande process och däribland borrning.Verktygskostnader har stor påverkan på den totala tillverkningskostnaden då till exempel ett heltarbetsstycke i värsta fall kan gå förlorat vid verktygshaveri. Genom sitt arbete med ständigaförbättringar håller Scania sig konkurrenskraftiga med sina produkter av hög kvalitet. I dettaexamensarbete inom masterprogrammet Industriell Produktion på KTH har en specifik typ av borrmed löstagbar borrkrona utvärderats med avsikt att undersöka nya fabrikat.Uppdragsgivaren var motorbearbetningen (DM) på Scania i Södertälje. Arbetet inleddes med attinförskaffa relevant kunskap gällande verktyget som undersöktes. Samtidigt utfördes ennulägesanalys där de använda borrarna på DM kartlades tillsammans med information kring pris,livslängd, m.m. Utifrån kartläggingen sammanställdes statistik som analyserades för att identifierahur stor påverkan en eventuell standardisering skulle kunna ha.Utvärderingen av borrar bestod av praktiska experiment där sju olika verktyg med en diameter på12,2 mm testades under samma förhållanden. Testet utformades i enighet med berörda parter påDM samt efter studier av adekvat litteratur rörande borrexperiment. Fyra parametrar testadesutöver borrarnas livslängd. Dessa var axialkraft, förslitning, håldiameter och spånor. Parametrarnaämnades jämföras och analyseras för att dra slutsatser kring borrarnas prestationer.Nulägesanalysen visade att ett fabrikat utgjorde hela 69% av borrarna på hela DM. Efter slutfördaborrtester hade enbart tre av sju genomfört utan haveri, Borr E, F och G. Samtliga sju borrar visadegodkända spånor och höll sig inom toleranserna för angiven håldiameter. Axialkrafterna varierademellan borrarna där Borr F hade lägst krafter och Borr A högst. Borr E visade bäst motstånd motförslitningar. Utifrån detta valdes borrarna E, F och G att rekommenderas för deras goda prestationermed Borr E på första plats. Utöver det föreslogs att utbudet av fabrikat som kan användas på DMbegränsas för att uppnå kostnadsbesparingar gällande verktygen.Drilling is a common cutting process within manufacturing. Tool costs have great influence on thetotal manufacturing cost since a tool break down can cause an entire work piece to be scrapped.Through their constant work with improvements, Scania stays competitive with their high qualityproducts. This Master Thesis in Industrial Production and Management at KTH has evaluated aspecific type of drill with indexable heads with the purpose of investigating new brands.The Engine Manufacturing department (DM) at Scania in Södertälje requested this project. The taskwas initiated by obtaining knowledge about the tool that were to be investigated. Simultaneously ananalysis of the current state was performed where the drills at DM were mapped out withinformation regarding price, tool life, etc. The statistics were compiled and analysed to identify theeffect of an eventual standardisation.The evaluation consisted of practical experiments where seven different drills with a diameter of12,2 mm was tested under the same circumstances. The test was design in concurrence with affectedparts at DM and studies of adequate literature regarding drilling experiments. Four parameters weretested in addition to the tool life of the drills. These were axial force, tool wear, hole diameter andchips. The parameters were intended to be used for comparing and analysing in order to makeconclusions regarding the performance of the drills.The current state analysis showed that one brand represented 69% of the drills used at DM. Afterfinished drilling tests three out of seven drills managed to complete the test without tool breakdown. All drills produced chips that were acceptable and the measured diameters stayed within thegiven tolerances. The axial forces varied between the drill where Borr F had the lowest force and BorrA the highest. Borr E showed the best resistance against tool wear. From the results the drills thatwere recommended were Borr E, F and G because of their good performances with Borr E in the firstplace. Ultimately it was suggested to limit the amount of brands used at DM to achieve cost savingsregarding the tools.
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Alyassin, Waleed. "The influence of heat production relative to drill wear during osteotomy preparation by different implant drill systems a comparison study between ceramic and conventional implant drill systems /." Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/11068.
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Thesis (M.S.)--West Virginia University, 2010.Title from document title page. Document formatted into pages; contains vi, 41 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 37-41).
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Chenegrin, Kévin. "Identification et modélisation des phénomènes thermomécaniques mis en jeu lors du perçage à sec de l’Inconel 718." Thesis, Lyon, 2021. http://www.theses.fr/2021LYSEE002.
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Dans le contexte industriel actuel, les acteurs du secteur aéronautique et spatial cherchent à atteindre un haut niveau de performance pour la tenue en fatigue de pièces jugées critiques, tout en réduisant les dépenses associées à leur production. Cette industrie a été l’une des premières à faire de la maîtrise des procédés de fabrication un axe privilégié de sa recherche, car les conséquences de la rupture d’un composant en service peuvent être désastreuses, tant sur le plan économique que sur le plan humain. Parmi les différents procédés existants, l’usinage représente encore aujourd’hui une grande part dans la fabrication des pièces critiques en ébauche et en finition. À ce jour, le perçage demeure l’opération d’usinage la plus répandue dans l’industrie, mais reste une des moins étudiées en raison de la forme géométrique réalisée. En effet, la création de trous cylindriques empêche toute observation directe des mécanismes de coupe, rendant très complexe l’étude des phénomènes thermomécaniques mis en jeu à l’échelle du trou percé. En contexte industriel, l’opération de perçage à sec est d’autant plus pénalisante pour l’outil et la matière puisqu’elle résulte d’une absence significative de lubrification, causée par un aléa d’usinage. Dans une telle configuration, les transferts de chaleur jouent un rôle déterminant dans la génération des contraintes résiduelles. Le développement d’une stratégie originale, expérimentale et numérique, a permis d’identifier et de modéliser les phénomènes thermomécaniques mis en jeu lors du perçage à sec de l’Inconel 718. Ainsi, les contraintes résiduelles induites au niveau de la surface du trou ont pu être modélisées et confrontées à des analyses expérimentales par DRXIn the current industrial context, aerospace players seek to achieve a high level of performance for the mechanical resistance of critical components, while reducing production costs. This industry was one of the first to consider the control of manufacturing processes as a privileged axis of its research, since the consequences of in-service fatigue failure can be economically and humanly disastrous. Among the various existing processes, machining still represents a large part of the manufactured critical components obtained by roughing and finishing operations. Drilling remains the most common machining operation used in industry, but also one of the least studied due to the machined geometrical shape. Indeed, the creation of cylindrical holes prevents direct observation of the cutting mechanisms, making it difficult to study the thermomechanical phenomena involved in the drilled hole. In an industrial environment, dry drilling operation is very detrimental to the tool and the material because it results in a significant lack of lubrication, caused by a machining hazard. In this configuration, heat transfers play a crucial role in the generation of residual stresses. The development of an original experimental and numerical strategy made it possible to identify and modeling the thermomechanical phenomena involved in dry drilling of Inconel 718. Thus, residual stresses induced in the hole could be modeled and compared to XRD analyses
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Nguyen, Minh-Hoang. "PROPELA - procédé de perçage laser pour l'aéronautique." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0577/document.
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Le perçage est un procédé de fabrication répandu dans le milieu industriel. Le secteur aéronautique a recours à ce procédé pour usiner de nombreuses pièces. Les chambres de combustions en sont un exemple. Exposées à des cycles thermiques sévères, elles sont percées d’une multitude de trous de refroidissement. Chez Safran Helicopter Engines, motoriste spécialisé dans la conception de turbines à gaz pour hélicoptères, ce perçage est réalisé à l’aide d’un procédé d’usinage unique : le perçage par percussion laser à la volée. Ce procédé phare leur permet de réaliser des milliers de trous inclinés dans des tôles en matériaux réfractaires. Safran Helicopter Engines cherche à maintenir son avance dans la production de turbines en s’appuyant sur les innovations constantes du procédé de perçage. Ce travail de thèse s’est articule autour du développement d’un nouveau procédé de perçage laser. De manière à définir un procédé fiable et efficace, plusieurs stratégies de perçage sont étudiées via les possibilités offertes par un laser à fibre milliseconde de haute puissance. Les résultats obtenus laissent entrevoir des perspectives intéressantes en termes d’augmentation de cadence de production à qualité d’usinage équivalente. L’amélioration des performances a été démontrée expérimentalement sur un banc d’essais représentatif des machines de production. Des trous de 400 μm de diamètre incliné à 60o ont pu être réalisés avec un cycle de perçage raccourci au minimum d’un facteur 2. Cette thèse présente également des éléments de compréhension des phénomènes de formation d’un trou. Pour cela, une modélisation des processus thermo hydrodynamiques impliqués dans le procédé de perçage laser a été développée. Ce modèle basé sur une approche par éléments finis repose sur l’étude thermique au cours de l’interaction entre le faisceau laser et la matière. Une partie du modèle inclut les phénomènes de propagation du faisceau dans la cavité en cours de formation afin de traduire de manière plus réaliste le dépôt d’énergieDrilling is a well-known manufacturing process. The aeronautic industry uses this process to machine a lot of elements. Among them, we can mention turbine blades, fuel injectors, combustion chambers. The latter are exposed to serious thermal stresses. To limit their impacts, combustion chambers are drilled with multiples cooling holes. At Safran Helicopter Engines, engines manufacturer specialized in engines design for helicopters, drilling is performed with a unique machining process : on the fly laser percussion drilling. This flagship process allows drilling thousands of tilted holes on refractory materials. Safran Helicopter Engines seeks to preserve its leading position in turbo engines manufacturing by looking for steady innovative drilling process. This thesis is structured around the development of a new laser drilling process. To define a reliable and efficient process, several drilling strategies were studied through the possibilities offered by a high-power millisecond fiber laser. The presented results allow catching a glimpse of the possibilities of production improvement. The performance enhancement was established through experimentation with a test bench. Holes of 400 μm diameter with an angle of 60o were drilled with a reduced processing time thanks to this new drilling process. In this thesis, we also propose a theoretical approach describing the hole formation. A mathematical model, accounting for all the physical process taking place during the drilling process is introduced. This model is based on finite elements method and considers the laser beam propagation within the drilled holes by solving Maxwell equations
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Arif, Rabiae. "Etude mécanique et métallurgique du perçage d’une nuance d’acier inoxydable austénitique réfractaire." Thesis, Paris, HESAM, 2020. http://www.theses.fr/2020HESAE013.
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Dans le cas de l’usinage des corps de turbocompresseurs (fraisage, perçage et taraudage) en acier inoxydableausténitique réfractaire (AIAR), les durées de vie des outils de coupe sont fortement altérées par rapport à desaciers standards de résistance mécanique équivalente. De ce fait, le coût de l’usinage de ces pièces, outilscoupants compris, constitue une part importante du prix de production. Dans le cas de leur perçage, la sévéritéde l’usinage est accrue et ceci d’autant plus qu’il repose sur des outils monoblocs étagés, complexes etcouteux.Ce projet de thèse vise à développer une nouvelle géométrie de coupe optimisée pour le perçage des AIAR.Dans cette optique, une caractérisation de l’outil de coupe est réalisée en se basant non seulement sur l’analysedes efforts de coupe locaux à partir d’une discrétisation des efforts de coupe globaux dans le régime transitoire,mais aussi sur la formation du premier copeau. Ensuite, une analyse in-situ du cumul de l’écrouissage de lasous-couche usinée est également réalisée en s’appuyant sur une identification de la déformation plastiqueéquivalente incrémentale. L’ensemble des analyses contribuent à la compréhension de la relationécrouissage/usinabilité pour les AIAR pour l’amélioration de la durée de vie des outilsIn the case of the turbocharger housings machining (milling, drilling and tapping operations) made of heatresistant austenitic stainless steel (HRASS), the tools life is greatly altered compared to standard steels ofequivalent mechanical resistance. Therefore, the machining cost of such pieces, including the cutting tools,constitutes a significant amount of their total cost. Concerning the drilling, the severity of the machining isincreased and even more since it relies on stepped, complex and expensive one-piece tools.This PhD project aims to develop a new cutting geometry optimized for the HRASS drilling. In thisperspective, a characterization of the cutting tool is carried out based on one hand on the local cutting forcesanalysis from a global cutting forces discretization during the drill tip penetration, and also on the initial chipformation. Then, an in-situ analysis of the cumulative strain hardening of the machined subsurface layer is alsocarried out using an identification of the incremental equivalent plastic strain. All the performed analysescontribute to the understanding of the strain hardening/machinability relationship for the tool life improvementof the HRASS dedicated drills
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Mitishita, Rodrigo Seiji. "Avaliação experimental da transmissão de pressão em tubulações preenchidas por fluidos viscoplásticos." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2598.
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CAPES; PetrobrasFluidos de perfuração apresentam comportamento viscoplástico, que é definido por uma tensão limite de escoamento. Se a tensão imposta não supera a tensão limite de escoamento, o material se comporta como um sólido elástico, e quando esta tensão é excedida, o fluido escoa como um líquido viscoso. Durante o processo de perfuração de poços de petróleo, válvulas posicionadas na extremidade da coluna de perfuração são atuadas por diferenças de pressão no fluido. Argumenta-se, entretanto, que pressões aplicadas na superfície não são totalmente transmitidas até a válvula, impedindo sua operação. Logo, a transmissão de pressão em fluidos viscoplásticos demanda mais estudo. Para suprir a falta de estudos experimentais sobre o assunto, uma avaliação experimental da transmissão de pressão em um fluido viscoplástico é realizada neste trabalho. O aparato experimental construído para este propósito consiste de uma longa tubulação em formato helicoidal (serpentina) mantida sob temperatura controlada, ao longo da qual estão instalados transdutores de pressão relativa. O fluido é bombeado a uma vazão controlada por uma bomba do tipo helicoidal. Durante os testes, o fluido de trabalho é pressurizado na serpentina até um certo patamar ao mesmo tempo em que as pressões são medidas. Os resultados dos testes com fluidos viscoplásticos corroboram a literatura, que afirma que um fluido com tensão limite de escoamento confinado em uma tubulação fechada não transmite totalmente a pressão imposta na entrada ao longo do restante da tubulação. Além disso, foi observado que a diferença de pressão entre dois pontos da tubulação quando o fluido está em repouso é proporcional à tensão limite de escoamento deste fluido. Os resultados experimentais foram comparados com resultados de simulações numéricas de dois modelos matemáticos desenvolvidos no Centro de Pesquisas em Reologia e Fluidos Não newtonianos (CERNN), com boa concordância.
Drilling fluids exhibit a viscoplastic behavior, which is defined by a yield stress. If the stress imposed to the fluid does not surpass the yield stress, the material behaves like an elastic solid; if the yield stress is exceeded, it flows like a viscous liquid. In well drilling operations, some valves installed on the drillpipe near the bottom of the hole are actuated by pressure differences in the drilling fluid. However, it has been argued that the pressure applied at the surface is not fully transmitted to the valve’s position, preventing its actuation. Therefore, the pressure transmission in viscoplastic fluids demands further investigation. In order to compensate for the lack of experimental studies about the problem, an experimental analysis of the pressure transmission in yield stress fluids has been performed in this work. The experimental rig consists of a long thermally-controlled helical pipe, on which are installed relative pressure transducers. Fluid is displaced by a helical pump at a controlled flow rate. During the experiments, the fluid is pressurized inside the closed pipeline while the pressures are measured and recorded. The results showed that, in agreement with literature, the pressure at one end of a closed pipeline filled with a yield stress fluid is not fully transmitted to the other end. Moreover, it was observed that the pressure gradient in the pressurized fluid is proportional to its yield stress, which indicates a relation between pressure transmission and the presence and magnitude of the yield stress. The experiments were compared to simulation work developed at the Research Center for Rheology and Non-Newtonian Fluids with good agreement.
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Amewoui, Ekoue-Adjoka Foli Noël. "Impact de l’opération de perçage sur l’intégrité des tissus osseux : modélisation et expérimentation." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0095.
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Le perçage de l’os est couramment pratiqué dans de nombreux types de chirurgie comme lors de la pose de vis d’ostéosynthèse et d’implants dentaires et cochléaires. Lors de l'opération de perçage, le chargement thermomécanique dû à l'interaction outil-os peut endommager les tissus osseux au voisinage de la zone de perçage. Ainsi, une augmentation significative de la température peut provoquer une ostéonécrose thermique. Il est donc important d'optimiser les conditions opératoires (vitesses de rotation et d'avance, géométrie du foret, stratégie de perçage...) afin de réduire les risques d'endommagement de l'os. Pour ce faire, il faut analyser et comprendre les effets des conditions de coupe sur les mécanismes contrôlant l'interaction foret-os. Les travaux de cette thèse ont pour objectif de contribuer à la compréhension de ces mécanismes en combinant une approche expérimentale avec de la modélisation numérique et analytique. L'étude expérimentale porte sur l’effet de la vitesse de coupe, de l’avance du foret et de la microstructure de la zone percée sur l’évolution des efforts de coupe (l'effort d'avance et le moment axial) et de l’augmentation de la température pendant le perçage d’un échantillon d’os porcin et de matériaux de tests biomécaniques (Sawbones). Ces derniers présentent l'avantage d'une microstructure uniforme par échantillon donné contrairement à l'os. Les modèles numériques de la coupe orthogonale et du perçage de l’os cortical sont développés en utilisant le code Eléments Finis ABAQUS/Explicit. L’objectif est d'analyser l’influence des lois de comportement et d’endommagement sur les prédictions du modèle (mécanisme de coupe, température et efforts de coupe). Afin de proposer une approche simplifiée, une modélisation analytique basée sur la théorie de la source mobile a également été proposée. La validation expérimentale a montré la pertinence des approches proposées ainsi que leurs limitesBone drilling is commonly practised in various surgical operations for orthosynthesis screws insertion or placement of dental and cochlear implants. During bone drilling procedure, the thermomechanical constraints resulting from the tool-bone interaction can damage the bone tissues in the vicinity of the drilling area. Thus, a significant increase in temperature can cause thermal osteonecrosis. It is therefore important to optimize the operating conditions (spindle speed and feed rate, geometry of the drill, drilling operation strategy ...) in order to reduce the risk of damage to bone tissues. To do this, it is necessary to analyse and understand the effects of cutting conditions on the mechanisms controlling the drill-bone interaction. The present work aims to contribute to the understanding of these mechanisms by combining an experimental approach with numerical and analytical modelling. The experimental study investigates the effect of the cutting speed, feed rate of the drill and the microstructure of the drilled area on the resulting cutting forces (thrust force and axial torque) and temperature rise during the drilling of porcine bone specimens and biomechanical test materials (Sawbones). These materials have the advantage of a uniform microstructure per given sample unlike bone. Numerical models of orthogonal cutting and bone drilling are implemented using the Finite Element code ABAQUS / Explicit. The purpose of this development is to analyse the influence of bone constitutive and damage laws on the model predictions (cutting mechanism, temperature and cutting forces). In order to propose a simplified approach, an analytical modelling based on moving heat source theory is developed for predicting bone thermal response. The relevance and limits of the approach proposed is shown through experimental validation
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Neuwirth, Filip. "Hotel." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-410064.
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The diploma thesis processes project documentation for the construction of a hotel building with a restaurant facility, which is situated on the outskirts of the western undeveloped part of the regional town Jihlava. The building has three floors and is covered by flat roofs. The hotel meets the conditions of a four-star (****) economic standard. It is designed with 24 accommodation units with a capacity of total 52 persons (4 persons with reduced mobility on the 3rd floor) and restaurant service for 92 guests, social facilities and kitchens. The apartments and guest rooms are located on the 2nd and 3rd floor. On the ground floor there is a representative space of the hotel composed of the entrance hall with reception , space for hotel management, space for technical facilities of the building and restaurant with its own kitchen. The building meets the requirements for zero-energy buildings with a combination of a high-quality construction solution with thermal insulation of building and other technological solutions such as photovoltaic power plants or deep boreholes for stepping pump heating The overall character of the building is emphasized by its architectural design in the light of modern lining of the ventilated facade using cement-fiber boards, whose two-color articulation emphasizes both simplicity and shape function of the building. This solution is combined with large glazed areas that give the building a feeling of spaciousness and evocative cleanliness.
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Hallqvist, Karl. "Högtempererat borrhålslager för fjärrvärme." Thesis, Uppsala universitet, Naturresurser och hållbar utveckling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-231586.
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The district heating load is seasonally dependent, with a low load during periods of high ambient temperature. Thermal energy storage (TES) has the potential to shift heating loads from winter to summer, thus reducing cost and environmental impact of District Heat production. In this study, a concept of high temperature borehole thermal energy storage (HT-BTES) together with a pellet heating plant for temperature boost, is presented and evaluated by its technical limitations, its ability to supply heat, its function within the district heating system, as well as its environmental impact and economic viability in Gothenburg, Sweden, a city with access to high quantities of waste heat. The concept has proven potentially environmentally friendly and potentially profitable if its design is balanced to achieve a good enough supply temperature from the HT-BTES. The size of the heat storage, the distance between boreholes and low borehole thermal resistance are key parameters to achieve high temperature. Profitability increases if a location with lower temperature demand, as well as risk of future shortage of supply, can be met. Feasibility also increases if existing pellet heating plant and district heating connection can be used and if lower rate of return on investment can be accepted. Access to HT-BTES in the district heating network enables greater flexibility and availability of production of District Heating, thereby facilitating readjustments to different strategies and policies. However, concerns for the durability of feasible borehole heat exchangers (BHE) exist in high temperature application.Värmebehovet är starkt säsongsberoende, med låg last under perioder av högre omgivningstemperatur och hög last under perioder av lägre omgivningstemperaturer. I Göteborg finns en stor mängd spillvärme tillgängligt för fjärrvärmeproduktion sommartid när behovet av värme är lågt. Tillgång till säsongsvärmelager möjliggör att fjärrvärmeproduktion flyttas från vinterhalvår till sommarhalvår, vilket kan ge såväl lönsamhet som miljönytta. Borrhålsvärmelager är ett förhållandevis billigt sätt att lagra värme, och innebär att berggrunden värms upp under sommaren genom att varmt vatten flödar i borrhål, för att under vinterhalvåret användas genom att låta kallt vatten flöda i borrhålen och värmas upp. I traditionella borrhålsvärmelager används ofta värmepump för att höja värmelagrets urladdade temperatur, men på grund av höga temperaturkrav för fjärrvärme kan kostnaden för värmepump bli hög. I denna rapport föreslås ett system för att klara av att nå höga temperaturer till en lägre kostnad. Systemet består av ett borrhålsvärmelager anpassat för högre temperaturer (HT-BTES) samt pelletspannor för att spetsa lagrets utgående fluid för att nå hög temperatur. Syftet med rapporten är att undersöka potentialen för detta HT-BTES-system med avseende på dess tekniska begränsningar, förmåga till fjärrvärmeleverans, konsekvenser för fjärrvärmesystemet, samt lönsamhet och miljöpåverkan. För att garantera att inlagringen av värme inte är så stor att priset för inlagrad värme ökar väsentligt, utgår inlagringen från hur mycket värme som kyls bort i fjärrvärmenätet sommartid. I verkligheten finns betydligt mer värme tillgänglig till låg kostnad. När HT-BTES-systemet producerar fjärrvärme, ersätts fjärrvärmeproduktion från andra produktionsenheter, förutsatt att HT-BTES-systemets rörliga kostnader är lägre. I Göteborg ersätts främst naturgas från kraftvärme, men också en del flis. Kostnadsbesparingen beror på differensen för total fjärrvärmeproduktionskostnad med och utan HT-BTES-systemet. Undersökningen visar att besparingen är större om HT-BTES-systemet placeras i ett område där det är möjligt att mata ut fjärrvärme med lägre temperatur. Om urladdning från HT-BTES kan ske med hög temperatur ökar också besparingen. Detta sker om lagrets volym ökar, om avståndet mellan borrhål minskar eller om värmeöverföringen mellan det flödande vattnet i borrhålen och berggrunden ökar. Dessa egenskaper för lagret leder också till minskade koldioxidutsläpp. Storleken på besparingen beror dock i hög grad på hur bränslepriser utvecklas i framtiden. Strategiska fördelar med HT-BTES-systemet inkluderar; minskad miljöpåverkan, robust system med lång teknisk livslängd (för delar av HT-BTES-systemet), samt att inlagring av värme kan ske från många olika produktionsenheter. Dessutom kan positiva bieffekter identifieras. Undersökningen visar att HT-BTES-systemet har god potential att ge lönsamhet och minskad miljöpåverkan, och att anläggning och drift av lagret kan ske utan omfattande lokal miljöpåverkan. Det har också visats att de geologiska förutsättningarna för HT-BTES är goda på många platser i Göteborg, även om lokala förhållanden kan skilja sig åt. För att nå lönsamhet för HT-BTES-systemet krävs en avvägning på utformning av lagret för att nå hög urladdad temperatur utan att investeringskostnaden blir för stor. Undersökningen visar att om anslutning av HT-BTES-systemet kan ske mot befintlig anslutningspunkt eller till befintlig värmepanna kan investeringskostnaden minska och därmed lönsamheten öka. Placering av HT-BTES-systemet i områden med risk för överföringsbegränsningar kan också minska behovet av att förstärka fjärrvärmenätet, och således bidra till att minska de kostnader som förstärkning av nätet innebär. Betydelsefulla parametrar för att nå lönsamhet för HT-BTES-system inkluderar dessutom kostnaden för inlagrad värme liksom vilket vinstkrav som kan accepteras. Tillgång till HT-BTES möjliggör ökad nyttjandegrad och flexibilitet för fjärrvärmeproduktionsenheter, och därmed ökad anpassningsmöjlighet till förändrade förutsättningar på värmemarknaden. Dock återstår att visa att komponenter som klarar de höga temperaturkraven kan tillverkas till acceptabel kostnad.
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Huang, Kuan-Jen, and 黃冠仁. "Study on Head Forging of SUS302 Stainless Steel Self-Drilling Screw." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/59342886020660554357.
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碩士高苑科技大學
機械與自動化工程研究所
101
The study aims at head of SUS302 stainless steel self-drilling screw to do forging simulation analysis. Assuming constant shear friction, the simulation and analysis of the one die and two passes are carried out using DEFORM-3D finite element analysis software. By means of realistic cylinder compression to obtain flow stress of material, and the frictional factor can be found by using FEM combining with the compression. The CAD files of dies and work-pieces are constructed by Solid Works software to be pre-process needed in DEFORM-3D to obtain 2 passes forming simulation. Besides, the effects of various taper arc for the first pass on forming characteristics can be explored to figure out the good forming conditions of self-drilling screw. Furthermore, the effective stress, the effective strain, the velocity field, and the forging force can be found. Finally, comparisons between simulation results and realistic product can be performed to verify the acceptance of FEM simulation. Keywords:Stainless steel self-drilling screw, Constant shear friction, Taper angle, Frictional factor
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Feng, Ming. "The Temperature Prediction in Deepwater Drilling of Vertical Well." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9413.
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The extreme operating conditions in deepwater drilling lead to serious relative problems. The knowledge of subsea temperatures is of prime interest to petroleum engineers and geo-technologists alike. Petroleum engineers are interested in subsea temperatures to better understand geo-mechanisms; such as diagenesis of sediments, formation of hydrocarbons, genesis and emplacement of magmatic formation of mineral deposits, and crustal deformations. Petroleum engineers are interested in studies of subsurface heat flows. The knowledge of subsurface temperature to properly design the drilling and completion programs and to facilitate accurate log interpretation is necessary. For petroleum engineers, this knowledge is valuable in the proper exploitation of hydrocarbon resources. This research analyzed the thermal process in drilling or completion process. The research presented two analytical methods to determine temperature profile for onshore drilling and numerical methods for offshore drilling during circulating fluid down the drillstring and for the annulus. Finite difference discretization was also introduced to predict the temperature for steady-state in conventional riser drilling and riserless drilling. This research provided a powerful tool for the thermal analysis of wellbore and rheology design of fluid with Visual Basic and Matlab simulators.
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Huang, Yi-Feng, and 黃一峯. "High frequency heat assisted drilling of difficult to machining materials." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/92q8sc.
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碩士國立雲林科技大學
機械工程系
107
In current aerospace industry, nickel-base superalloy wide range of applications, for production speed and quality requirements are also more attention. Its alloy son of high strength, low thermal conductivity, processing hardening and other characteristics make it face many problems in processing, such as tool rapid wear, poor surface roughness, processing efficiency is limited. Therefore, the above problems are improved by thermal assistance. Thermal assisted machining technology refers to the use of a heat source before cutting the local surface of the material, so that the material heating to achieve a softening effect, reduce the strength of the material itself to the tool cutting. At present, researches on nickel-based alloy cutting at home and abroad are mostly for turning and milling, while research on drilling is relatively rare. Research on heat-assisted machining also fuses on turning and milling. Through the concept of composite machining, this paper combines CNC milling machine with high-weekly heating machine for thermal auxiliary drilling, explores the tool life, tool wear, hole quality, surface roughness of the inner hole at different machining temperatures, finds the best operating temperature, and compares with dry drilling and wet drilling. From the experimental results, it is found that the life of the high-weekly wave thermal-aided drilling tool can reach 63 holes compared to the general dry drilling 5 holes has a substantial improvement , but slightly less than the 73 holes that were processed in wet.
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Ho, Shao-Chun, and 何邵濬. "Effect Of Core Drilling On The Properties Of Heat-treated Wood With Large Cross Section." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/22697467020340376139.
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碩士國立宜蘭大學
森林暨自然資源學系碩士班
100
Three wood species include Japanese cedar (Cryptomeria japonica), southern yellow pine (Pinus spp.), and Douglas fir (Pseudotsuga menziesii) with larger cross section of 14 × 14 cm and 50 cm in the length were used in this study. Heat treatments were carried out at temperature levels of 170℃, 190℃, 210℃, and 230℃ for holding time spans of 1h, 2h, and 4h in a heating unit. The objective of this study was to investigate the effects of core drilling process on the visual grades, physical, and mechanics properties of heat-treated wood specimens. The results showed that the hygroscopicity and dimensional stability of wood could be significantly improved after heat treatment. There could be over 60% increase in the MEE(Moisture Excluding Efficiency) and ASE(Anti Shrinkage Efficiency) compared to the control specimens. The values of MEE and ASE of Japanese cedar treated at temperature levels of 170℃ and 190℃ were significantly higher than those of Douglas fir and southern yellow pine. Some degree of loss in the mass, volume, and over-dry density of test specimens were found after heat treatment. Maximums reduction values for mass and volume were respectively around 18% and 10% of test samples treated at 230℃ for 4 h. The over-dry density of wood specimens were less affected by heat treatment at temperatures of 170℃ and 190℃, moreover, some of them were increased. A darkening of three wood species occurred, with the color change being related to the temperature and time of treatment. The color difference between sapwood and heartwood of Japanese cedar was obviously reduced after thermal modification process. The defects occurred in the core-drilled specimens after heat treatment were significantly lower than those of control samples. These was a slight increase in MOE when three wood species were thermally treated. However, the rate of increase in MOE was subsequent decreased with higher heating temperatures. The values of MOE for Japanese cedar and southern yellow pine treated at temperature of 230℃ were lower than those of untreated samples, while for specimens of Douglas fir were still higher than controls. The bending properties of Douglas fir were less affected by heat treatment compared to the other species in this study. The values of compression strength parallel to grain increased for test species after heat treatment. The rate of increase in compression strength parallel to grain was subsequent decrease with higher heating temperatures and time of periods. The surface roughness of heat-treated specimens were lower than those of untreated samples. The abrasion resistance of wood surface decreased with an increasing in treated temperature.
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YiHuang and 黃奕. "Effects of Two-Step Heat Treatment on Microstructure and Mechanical Properties of 10B21 Low Carbon Steel Self Drilling Tapping Screws." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3cvfpx.
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何慶炎. "= Energy absorption in a welding or drilling cavity and heat transfer of the fusion zone subject to a high-intensity beam." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/87658103468327408572.
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