Mud pumps used on offshore installations for drilling operations have been known to experience unpredictable breakdowns, including during critical stages of drilling. The fluid end has been identified as requiring more maintenance work due to component failure, compared to the power end. The most common maintenance strategies in use include breakdown maintenance, time-based maintenance and condition monitoring. Time-based maintenance, based on running hours, is the most commonly preferred method by most, if not all, mud pump operators. However, the nature of drilling operations require pump performance with variable loads (pressures), variable speed characteristics and time-based maintenance would not be able to account for the different operating conditions within any identical time frames. To address this shortcoming, this research looked at the postulation that material wear loss is related to the energy expended and developed a dedicated reciprocating wear test system to identify and investigate the effect of operating variables on the wear loss of piston rubbers, which was considered to be the most problematic of the fluid end components.

Drag embedment anchors (DEAs, or anchors) are used as foundations to secure mobile offshore drilling units (MODUs) in soft clay soils on the sea floor. In 2004 and 2005, Hurricanes Ivan, Katrina, and Rita caused the mooring failures of 17 mobile offshore drilling units moored with anchors. Since then, a great deal of research has been conducted regarding anchor performance and reliability. This report provides an overview of anchor research and industry practice to date, and discusses the results of two research experiments to assess anchor performance. One experiment investigated the effect that embedding anchors in the same soil path several times had on bearing force. The second experiment investigated what effect changing the direction of the horizontal load vector relative to the anchor shank had on embedded anchor bearing force. The results of these experiments suggest that remolding clay may have an effect on anchor bearing force capacity, and that repeatable results are obtainable when testing the effect of changing the direction of applied horizontal load. / text

In my dissertation, I investigate the effects of budget-constraints in multi-unit auctions. This is done in three parts. First, I analyze a case where all bidders have a common budget constraint. Precisely, I analyze an auction where two units of an object are sold at two simultaneous, sealed bid, first-price auctions, to bidders who have demand for both units. Bidders differ with respect to their valuations for the units. All bidders have an identical budget constraint which binds their ability to spend in the auction. I show that if valuation distribution is atom-less, then their does not exist any symmetric equilibrium in this auction game. In the second and third parts of my thesis, I analyze the sale of licenses for the right to drill for oil and natural gas in the Outer Continental Shelf (OCS) of the United States. These sales are conducted using simultaneous sealed-bid first-price auctions for multiple licenses, each representing a specific area (called a tract). Using aspects of observed bidding-behavior, I first make a prima facie case that bidders are budget-constrained in these auctions. In order to formalize this argument, I develop a simple extension of the standard model (where bidders differ in their valuations for the objects) by incorporating (random) budgets for the bidders. The auction-game then has a two-dimensional set of types for each player. I study the theoretical properties of this auction, assuming for simplicity that two units are being sold. I show that this game has an equilibrium in pure strategies that is symmetric with respect to the players and with respect to the units. The strategies are essentially pure in the sense that each bidder-type has a unique split (up to a permutation) of his budget between the two auctions. I then characterize the equilibrium in terms of the bid-distribution and iso-bid curves in the value-budget space. I derive various qualitative features of this equilibrium, among which are: (1) under mild assumptions, there always exist bidder-types who submit unequal bids in equilibrium, (2) the equilibrium is monotonic in the sense that bidders with higher valuations prefer more unequal splits of their budgets than bidders with lower valuations and the same budget-level. With a formal theory in place, I carry out a quantitative exercise, using data from the 1970 OCS auction. I show that the model is able to match many aspects of the data. (1) In the data, the number of tracts bidders submit bids on is positively correlated with budgets (an R² of 0.84), even though this relationship is non-monotonic; my model is able to capture this non-monotonicity, while producing an R² of 0.89 (2) In the data, the average number of bids per tract is 8.21; for the model, this number is 10.09. (3) Auction revenue in the data was $1.927 billion; the model produced a mean revenue of $1.944 billion

Mobile offshore drilling units are being used in the Gulf of Mexico to produce oil and gas. Anchoring systems such as drag embedment anchors and vertically loaded anchors are used to keep these units in place. Past mooring system failures due to hurricanes in 2004 and 2005 initiated a need to better understand the performance of these anchors to in-plane and out-of-plane loading conditions. In-plane and out-of-plane loading cause the anchor to translate or rotate in the directions of its six degrees of freedom. Behavior and holding capacity of the anchors when loaded in each of is six degrees of freedom are important in understanding and predicting their behavior. An experimental program was devised to investigate the behavior of anchors in pure translation and rotation loading. The scaled-model anchors were embedded at a measured depth in a soil bed of clay with an undrained shear strength between 10 and 20 psf and then loaded to failure. A rotation testing frame was designed to impose rotational loading in the yaw, roll and pitch directions. Test results from the experimental program are consistent and repeatable. The bearing factors for pure bearing fell well within the range of existing experimental and analytical studies on simple plates. Bearing factors for in-plane and out-of-plane shear and for all rotations are higher than those for simple plates due to presence of the shank. When the resistance is normalized by area of the fluke, the wider model provide greater normalized resistance to yawing, similar normalized resistance to pitching and rolling and less normalized resistance to bearing and shearing. It was concluded that the holding capacity of an anchor in its six degrees of freedom depends largely on its geometry, including the fluke and the shank. / text

Orientador: Celso Kazuyuki Morooka / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-29T00:17:50Z (GMT). No. of bitstreams: 1 Yamamoto_Marcio_M.pdf: 8268362 bytes, checksum: d7360bb0a9c0c1aed1900c2637804300 (MD5) Previous issue date: 2007 / Resumo: Para a perfuração de poços de petróleo sob águas ultra-profundas (acima de 1500 m de profundidade), é necessária a instalação na cabeça do poço do equipamento de segurança do poço chamado de Preventor de Erupção, ou BOP. Este equipamento é descido pendurado pelo riser de perfuração, e esta operação é conhecida como Reentrada no Poço. Durante a aproximação do BOP ao poço, o equipamento é mantido suspenso sobre a cabeça do poço através do riser de perfuração, e a extremidade superior do riser fica engastada na plataforma flutuante de perfuração. Nesta dissertação de mestrado, a análise dinâmica dos dois sistemas dinâmicos acoplados (riser e plataforma) é realizada através de simulação numérica no domínio do tempo. Um programa computacional foi desenvolvido, que emprega um modelo não-linear para a dinâmica da plataforma flutuante e outro modelo utilizando o Método dos Elementos Finitos para a dinâmica do riser. O sistema de Posicionamento Dinâmico (DP) da plataforma, que é responsável em manter a posição da plataforma dentro de um raio de tolerância sobre a cabeça do poço, também foi incluído no modelo numérico. Um sistema de controle realimentado para controlar a aproximação do BOP à cabeça do poço é proposto. Discussões a respeito da otimização do controle realimentado a fim de minimizar o tempo gasto para a reentrada do poço são realizadas / Abstract: During the drilling of petroleum wells in ultra-deep water (more than 1500 m of water depth), it is necessary to assembly a piece of safety equipment called Blowout Preventer, or BOP, on the wellhead. The BOP is lowered hung by the drilling riser; this installation operation is called the Reentry Operation. During the well approach, the BOP is kept suspended above the wellhead by the drilling riser, and the upper end of the riser is fixed at the rig floor of the floating platform rig. In this work, the analysis of the dynamics of the coupled system (platform and riser) is carried out using numerical simulation in the time domain; the software was developed using a nonlinear model for the floating platform dynamics and the Finite Element Method for the riser dynamics. The Dynamic Positioning (DP) system, that keeps the platform position into a tolerance radius on the wellhead position, is also included in the numerical simulation. A feedback control system that controls the BOP approach is proposed. Discussions are carried out on the feedback control system which is developed to reduce the operational time of the reentry operation / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo

The master's thesis contains 97 pages, 29 tables, 33 figures and 43 sources of literature. The paper presents a study on increasing the efficiency of the power supply of remote offshore oil and gas facilities through the use of horizontal-axial tidal stream turbines. A general theoretical description of floating semi-submersible drilling rigs and a more detailed description of semi-submersible drilling unit 6000/200 type "Shelf" are presented. A theoretical description of various devices that transform the kinetic energy of water into electric power is also presented, and horizontal-axial tidal stream turbines are considered in more detail. The technical calculation for determining the parameters of turbines is carried out. The calculation was used for the case where one or several turbines are used. Economic analysis was carried out with different indicators, namely: the price of diesel fuel, the price of equipment, the load factor of hydro generators, the discount rate and the productivity of the drilling unit. An analysis of the reduction of carbon dioxide emissions was also carried out. Conclusions were presented on the effectiveness of the introduction of this method of energy supply. / Magisteruppsatsen innehåller 97 sidor, 29 tabeller, 33 figurer och 43 litteraturkällor. I papperet presenteras en studie om att effektiviteten i kraftförsörjningen av avlägsna offshore olje- och gasanläggningar ökar genom användning av horisontella axiella tidvattenströmsturbiner. En generell teoretisk beskrivning av flytande halvdämpbara borriggar och en mer detaljerad beskrivning av semi-submersible borrningsenhet 6000/200 typ "Hylla" presenteras. En teoretisk beskrivning av olika anordningar som omvandlar den kinetiska energin hos vatten till elkraft presenteras också, och horisontella axiella tidvattenströmsturbiner behandlas mer detaljerat. Den tekniska beräkningen för att bestämma parametrarna för turbiner utförs. Beräkningen användes för det fall där en eller flera turbiner används. Ekonomisk analys utfördes med olika indikatorer, nämligen: priset på dieselbränsle, priset på utrustning, belastningsfaktorn för hydrageneratorer, diskonteringsräntan och borrningens produktivitet. En analys av minskningen av koldioxidutsläpp gjordes också. Slutsatser presenterades om effektiviteten av införandet av denna metod för energiförsörjning.

[pt] Este estudo apresenta uma unidade de tratamento móvel recentemente implantada em atividades marítimas de desenvolvimento de petróleo no Brasil. O sistema consiste em dois módulos de tratamento especializados para tratamento de fluidos de perfuração de base não aquosa (FBNA) contaminado com interface de deslocamento e águas residuárias da perfuração marítima. Os módulos componentes do sistema proposto podem ser instalados tanto em instalações em terra ou em plataformas marítimas. A unidade a ser avaliada utiliza a combinação dos tratamentos de demulsificação, floculação, decantação e filtração para separação de FBNA e frações de FBNA da água residual em seus principais componentes. Testes laboratoriais foram realizados de modo a garantir que o sistema teria a capacidade de tratar os resíduos de FBNA contaminado em conformidade às resoluções brasileiras de descarte de efluentes (Resoluções do Conselho Nacional do Meio Ambiente número 357/05 e 430/11). Os ensaios envolveram o ajuste do sistema para operar dentro dos limites estabelecidos pela legislação local, que estabelecem limites muito conservadores de metais e hidrocarbonetos, entre outros parâmetros, os quais os efluentes devem se enquadrar antes da permissão para descarte em águas continentais ou oceânicas. Este estudo apresenta os resultados dos ensaios, os quais demonstraram que os efluentes tratados pelo sistema estão em conformidade com os parâmetros necessários para permissão do descarte em locações de perfuração marítima no Brasil. O próximo passo a ser dado, antes do uso operacional desta recente tecnologia no Brasil, é o acordo de um Plano de Monitoramento Ambiental com o Órgão Ambiental. Os resultados mostraram que o uso do sistema não é apenas economicamente vantajoso, mas também ambientalmente importante, uma vez que ajuda a minimização de resíduos, reutilização de fluidos, aumento do lucro e melhora das margens em operações de perfuração. No Brasil, o uso desta tecnologia tem um perfil inovador e é uma ferramenta que pode contribuir para redução dos elevados volumes de resíduos de perfuração que são atualmente enviados para destinação final em terra. / [en] This study presents the mobile treatment system recently deployed in offshore development activities in Brazil. The system is a specialized two-module treatment of synthetic base mud (SBM) contaminated with wash water and slop water. The modules of the unit are deployable to any drilling environment onshore or offshore platforms. The studied unit treatment process uses a combination of chemical and physical processes such as demulsification, flocculation, settling and filtration to separate SBM and SBM fractions from the slop water into their main components. Laboratorial testing was conducted to ensure that this system would have the capacity to treat SBM-contaminated wastes to comply with the Brazilian Resolutions for Effluents Discharge (Conselho Nacional do Meio Ambiente Resolutions number 357/05 and 430/11). The tests involved adjusting the system to operate within the limits established by the local legislation, which establish very conservative limits of metals and hydrocarbons, amongst other parameters, that effluents have to meet before being allowed to be discharged in continental or oceanic bodies of water. The study presents the test results which show that the system has produced effluent that complies with all the parameters necessary to allow its discharge at the drilling offshore location in Brazil. The next step to be taken, before operational use of this technology in Brazil, is the agreement of a monitoring plan with the environmental agency. Results have shown that the use of such system is not only economically advantageous, but also environmentally significant as it helps minimize the waste, reuse fluid, increase profit, and improve margins in drilling operations. In Brazil, the use of this technology has an innovative profile and it is a tool that can contribute to reducing the high volumes of drilling waste that currently are sent onshore for final waste disposal.

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.

Orientadores: Celso Kazuyuki Morooka, Jose Ricardo Pelaquim Mendes, Kazuo Miura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica, Instituto de Geociências / Made available in DSpace on 2018-08-15T22:58:32Z (GMT). No. of bitstreams: 1 Chipindu_NjaloSocratesChipongue_M.pdf: 4694196 bytes, checksum: 6b99e27328776d4bdf9d03833efef6f0 (MD5) Previous issue date: 2010 / Resumo: Os problemas na perfuração de poços de petróleo são responsáveis pela maior parte dos tempos não produtivos, elevando assim os custos diários das operações. Portanto, o estudo e o entendimento destes problemas contribuirá para a otimização da perfuração, melhorando assim as práticas ou mitigando os efeitos severos das anormalidades. O presente trabalho apresenta três procedimentos para identificação das causas dos problemas que poderão auxiliar o jovem profissional a caracterizar os mais variados problemas que ocorrem durante a perfuração de um poço. Neste escopo são abordadas apenas as ocorrências pré-classificadas como dificuldade de manobra, dificuldade de avanço, e prisão. O estudo usa dados dos boletins diários de perfuração dos poços, dados de mudlogging, dados obtidos por ferramentas de monitoramento contínuo da perfuração e outros dados como o fluido utilizado, a configuração da composição de fundo, o desgaste de broca, o gráfico do caliper, litologia e trajetória do poço. A caracterização dos problemas é feita mediante a identificação e associação de eventos que levam a formular hipóteses das prováveis causas dos problemas. Dois grupos de pesquisa (Unicamp e Genesis do Brasil) em engenharia de poço implementaram separadamente os procedimentos propostos. Os resultados foram coincidentes para a maioria trechos de poços marítimos de desenvolvimento analisados, o que atesta a eficácia dos procedimentos diagnósticos. Este estudo é importante para indústria, pois pode maximizar a eficiência na perfuração, através da minimização e/ou eliminação dos tempos não produtivos, responsáveis por avultadas perdas econômicas, além de permitir tornar mais robustas as ferramentas de acompanhamento, em tempo real, das operações de perfuração, na tomada de decisões e na melhoria do processo de planejamento de poço / Abstract: Drilling problems are accountable for the majority of the non productive times in the industry raising the daily operations costs. Therefore, the study and understanding of the problems will contribute to the drilling optimization, improving the practices or by mitigating their severe effects. The present work presents three procedures for identification of causes of drilling problems which can help the young professionals to characterize a wide range of problems that occur while drilling an oil well. In this scope they are studied only the problems pre-classified by occurrence as: problems in tripping, problem in drilling ahead and stuck pipe. The study uses data from the daily drilling reports, mudlogging data, on time monitoring tools data and mud data, Bottom Hole Assembly composition, bit wear report, caliper data, litology and well trajectory. The characterization of the problems is made by identification and association of the events that lead to formulate the hypotheses of the probable causes of the problems. Two research groups (Unicamp and Genesis do Brasil) in well engineering implemented separately the three proposed procedures. The results were coincident for the majority of the analyzed intervals of offshore development wells, demonstrating the efficacy of the proposed procedures. This work is important to the industry since it leads to the drilling efficiency maximization by minimization and/or elimination non productive times that are the main responsible for economic losses, beside the fact that these findings can be used to boost the capacity of the monitoring and logging tools as well as to support the on time decision making and to improve well planning process / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo

Orientador: Celso Kazuyuki Morooka / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-30T02:08:44Z (GMT). No. of bitstreams: 1 Chagas_BrunoLuizBarbosadas_M.pdf: 3797109 bytes, checksum: 1ef50f3d002aa234dbe301fd26044c8f (MD5) Previous issue date: 2015 / Resumo: O presente trabalho tem como objetivo principal avaliar a probabilidade de falha por fadiga em um riser de perfuração. Os parâmetros mais importantes são identificados e sua influência na probabilidade de falha é analisada. De acordo com as premissas do comportamento dinâmico de um riser, a partir do qual se obtém o dano total à fadiga, juntamente com a teoria da confiabilidade e as variáveis de incerteza, aplicou-se o método FORM (First Order Reliability Method) determinando-se a probabilidade de falha por fadiga em um riser. O procedimento foi adotado para um campo marítimo em operação, a fim de se demonstrar a sensibilidade das variáveis envolvidas na função de estado limite. Neste estudo consideraram-se o expoente m da curva S-N e a constante K da curva S-N como sendo ora determinísticos ora probabilísticos. Assim sendo, a partir das premissas e procedimentos acima elencados, os resultados de probabilidade de falha para análise probabilística se mostraram mais sensíveis que a análise determinística nas quatro diferentes localizações críticas ao longo do comprimento do riser de perfuração / Abstract: The primary objective of this work is to evaluate the probability of fatigue failure in a drilling riser. Key parameters are identified and their influence on the probability of failure is analized. Based on riser dynamic behavior, which givestotal fatigue damage, along with the reliability theory and the variables of uncertainty, the method FORM (First Order Reliability Method) was applied to determine the probability of fatigue failure on a riser . The procedure was applied in a offshore field in operation in order to demonstrate the sensitivity of the variables involved in the limit state function.In this study the exponent m of the SN curve and the constant K of SN curve were considered to be either deterministic or probabilistic. Thus, according to adopted assumptions and procedures, the results of probability of failure for probabilistic analysis have shown to be more sensitive than deterministic analysis in the four different critical locations along the length of the drilling riser / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo