Diagnostic of Operation Conditions and Sensor Faults Using Machine Learning in Sucker-Rod Pumping Wells.

In sucker-rod pumping wells, due to the lack of an early diagnosis of operating condition or sensor faults, several problems can go unnoticed. These problems can increase downtime and production loss. In these wells, the diagnosis of operation conditions is carried out through downhole dynamometer cards, via pre-established patterns, with human visual effort in the operation centers. Starting with machine learning algorithms, several papers have been published on the subject, but it is still common to have doubts concerning the difficulty level of the dynamometer card classification task and best practices for solving the problem. In the search for answers to these questions, this work carried out sixty tests with more than 50,000 dynamometer cards from 38 wells in the Mossoró, RN, Brazil. In addition, it presented test results for three algorithms (decision tree, random forest and XGBoost), three descriptors (Fourier, wavelet and card load values), as well as pipelines provided by automated machine learning. Tests with and without the tuning of hypermeters, different levels of dataset balancing and various evaluation metrics were evaluated. The research shows that it is possible to detect sensor failures from dynamometer cards. Of the results that will be presented, 75% of the tests had an accuracy above 92% and the maximum accuracy was 99.84%.

CFD study and experimental validation of low liquid-loading flow assurance in oil and gas transport: studying the effect of fluid properties and operating conditions on flow variables.

Low liquid-loading flow frequently occurs during the transport of gas products in various industries, such as in the Oil & Gas, the Food, and the Pharmaceutical Industries. Even small amounts of liquid can have a significant effect on the flow conditions inside the pipeline, such as increased pressure loss, pipe wall stresses and corrosion, and liquid holdup along the pipeline. However, most studies that analyze this type of flow only use atmospheric pressures and horizontal 1-in or 2-in pipes, which do not accurately represent the range of operating conditions present in industrial applications. Therefore, this study focused on modeling low liquid-loading flow in medium-sized (6-10 in) pipes, using CFD simulations and experimental data from the University of Tulsa, and then applying it to real operating conditions from a Colombian gas pipeline. An acceptable difference was observed between experimental and CFD data, both for the liquid holdup (18%) and for the pressure drop (12%). Variables like pressure drop and wall shear stress increase with phase velocity, operating pressure, and pipe inclination. Liquid holdup increases with liquid velocity but decreases with all other factors. The relation of flow variables with phase velocities is of particular interest: Doubling the gas velocity decreased holdup 70% and increased pressure drop tenfold. On the other hand, the presence of the liquid phase seems to be more influential on process variables than its exact flowrate; the introduction of the liquid phase to a single-phase gas causes an increase in pressure loss by a factor of three, but doubling the liquid velocity only increases the pressure loss by a further 30%.

Flexible robotic teleoperation architecture for intelligent oil fields.

Teleoperation virtual platforms allow people to send their skills and capacities into machines located in either relative close (few meters away) or far (different continents) locations. With the use of lightweight protocols, people can remotely control the actions and movements of robots so they can avoid physical interaction with dangerous or risky places. Oil and gas well-pads stations are working zones considered hazardous due to the various chemical substances used in their daily processes. This characteristic makes these places the perfect candidates for the implementation of teleoperation solutions in order to reduce the direct interaction of humans with different chemicals and risky situations. The following investigation focuses on the development of a base teleoperation scheme to perform inspection and maintenance tasks in the inside one of these hydrocarbon facilities. The proposed system aims to generate an easily scalable teleoperation solution using distributed control schemes and a lightweight communication protocol to remotely manipulate a KUKA mobile manipulator. As the first stage of this investigation, the main result focuses on the development of the generic control and communication functions that allow the physical testing of the system using a KUKA YouBOT mobile manipulator and the help of a qualified operator of the station.

Could petroleum work as lubricant oil on slippery lubricated surfaces to prevent inorganic scaling?

The use of nucleation and growth inhibitors at offshore oil industry to avoid inorganic scaling could be replaced by both physical and chemical modifications at surfaces to prevent the scaling. In that way, the slippery lubricated surfaces have been showing promising results as scaling preventers, notably when the lubricants are perfluorinated oils, which are immiscible with almost every kind of compound. Nonetheless, the requirement of periodically refilling these lubricant oils is disadvantageous, especially when dealing with deep sea facilities. Using petroleum as the lubricant oil could skip the refilling step, since it is always present in the extraction medium. So, this work tests the effectiveness of petroleum as the lubricant oil in functionalized textured polyaniline applied as anti-scaling material in conditions that simulate the medium of offshore operation. As result, petroleum as lubricant oil presents effective anti-scaling capacity and works perfectly in slippery lubricated surfaces.

Fixed-bed study for bone char adsorptive removal of refractory organics from electrodialysis concentrate produced by petroleum refinery.

Water reuse in industrial processes has been an increasing need encouraged in recent years. However, as the streams are recycled, solutes accumulate, thus requiring purification techniques. Membrane processes (reverse osmosis and electrodialysis) have been implemented and in order to increase the reuse of water at its highest level, crystallization has been evaluated to remove salts from the concentrate produced and get a feasible disposal. Nevertheless, contaminants affect the crystallization performance, thus making the removal of residual organics important for both the efficiency of crystallization and the increase of water reuse. In this context, aiming at establishing a sustainable virtuous circle, bone char (0.5-1.4 mm particle size, mesoporous structure) was used to remove refractory organics from an electrodialysis concentrate effluent (C-EDR) from a Brazilian petroleum refinery, at a lab-scale, in a fixed-bed adsorption column. Bone char selectively and partially removed the refractory organics, a complex mixture of long-chain hydrocarbons, aromatic compounds, carboxylic acids, amines and amides. The maximum adsorption capacity increased with the increase in bed depth and reduction in flow rate. A maximum removal of 35.60 mg g-1 was achieved for the highest bed depth evaluated (12.9 cm). The breakthrough curves indicated that bone char could adsorb part of the organic compounds from the C-EDR. The scaling up was possible for the C/C0 ratios of 0.55, 0.60 and 0.65, providing a service time at about 16 days for 45% removal efficiency for typical real operational conditions used in the refinery.

Percepção da qualidade ambiental de localidades próximas ao Complexo Petroquímico do Rio de Janeiro, Brasil / Perception of environmental quality of nearby localities to the Petrochemical Complex of Rio de Janeiro, Brazil

Resumo O artigo tem por objetivo verificar a diferença da percepção de residentes sobre a qualidade ambiental de duas localidades próximas à área de construção do Complexo Petroquímico do Rio de Janeiro. Nove aspectos da qualidade ambiental (serviços de abastecimento de água, esgotamento sanitário e coleta de lixo; áreas de lazer; segurança pública; serviços de saúde; ruas; ar; rios) foram avaliados. Estudo transversal realizado com 240 residentes de Porto das Caixas e Manilha, ambos situados no município de Itaboraí-RJ, Brasil. A análise estatística envolveu o teste do qui-quadrado e exato de Fisher. Área de lazer foi o fator percebido igualmente pelos participantes das duas localidades do estudo com pior qualidade. A percepção da qualidade dos serviços de saúde, segurança e saneamento diferiu significativamente entre os moradores das duas localidades estudadas. A piora da qualidade ambiental foi relacionada por 51% dos residentes de Porto das Caixas à ausência de medidas mitigatórias após a ocorrência de um acidente químico local em 2005. A priorização de intervenções deve ser baseada na percepção de grupos populacionais específicos como estratégia que possa permitir a redução de iniquidades em saúde ambiental em contextos de instalação e construção de indústrias de petróleo e gás.

Abstract This article aims to verify the residents’ perception difference on the environmental quality of two localities near the construction area of the Petrochemical Complex of Rio de Janeiro. Nine environmental quality aspects (water supply services, sewage and garbage collection; leisure areas; public security; health services; streets; air; rivers) were evaluated. Cross-sectional study conducted with 240 residents of the Porto das Caixas and Manilha, both of them located in Itaboraí city, RJ state, Brazil. The statistical analysis involved the chi-square test and Fisher´s exact test. Leisure Area was the factor perceived also by participants of both locations of the study with worse quality. The quality perception of health services, security and sanitation differed significantly among the inhabitants of the two studied localities. The worsening of environmental quality was related by 51% of the residents of Porto das Caixas to the absence of mitigatory measures after the occurrence of a local chemical accident in 2005. The prioritization of interventions should be based on the perception of specific population groups such as strategy that can allow a reduction of environmental health inequities in installation and construction contexts of the oil and gas industries.

Saúde, ecologia de saberes e estudos de impactos ambientais de refinarias no Brasil / Health, ecology of knowledge and environmental impact studies on oil refineries in Brazil / Salud, ecología de los saberes y estudios de impactos ambientales de refinerías en Brasil

Este artigo apresenta uma análise de estudos de impactos ambientais de refinarias de petróleo. Realizou-se uma análise crítica sobre a saúde coletiva com vistas a propor uma ecologia de saberes alternativa ao modelo tradicional de construção de conhecimento no processo de licenciamento ambiental. Pesquisa qualitativa que utilizou a análise documental, para a coleta de dados, e a análise de conteúdo temático, para a análise dos resultados. Verifica-se que, no modo tradicional, há: fragmentação, reducionismo, desarticulação conceitual, omissão de realidades complexas, silenciamento sobre aspectos importantes para a garantia de direitos, saúde e denúncia de conflitos ambientais. Conclui-se que a elaboração de estudos de impactos ambientais é uma oportunidade para a prática da ecologia de saberes por meio da produção de conhecimentos compartilhada com os movimentos sociais, devendo traduzir-se em instrumento de defesa da vida, com vistas a ações de saúde coletiva e de proteção do ambiente...

This paper presents an analysis on environmental impact studies on oil refineries. Critical analysis on public health was undertaken with a view to proposing an ecology of knowledge that would form an alternative to the traditional model for knowledge construction within the environmental licensing process. This was a qualitative study using document analysis to gather data, and thematic content analysis to assess the results. It was noted that in the traditional mode, there was fragmentation, reductionism, conceptual disconnection, omission of complex realities and silence regarding important issues relating to guaranteed rights, health and complaints about environmental conflicts. It was concluded that development of environmental impact studies provides an opportunity for practicing ecology of knowledge through production of knowledge shared with social movements. This should translate into an instrument for defense of life, with a view to action promoting public health and environmental protection...

Este artículo presenta un análisis de estudios de impactos ambientales de refinerías de petróleo. Se realizó un análisis crítico sobre la salud colectiva con el objetivo de proponer una ecología de saberes alternativa al modelo tradicional de construcción de conocimiento en el proceso de licenciamiento ambiental. Estudio cualitativo que utilizó el análisis documental para la colecta de datos y el análisis de contenido temático para el análisis de los resultados. Se verifica que en el modo tradicional hay fragmentación, reduccionismo, desarticulación conceptual, omisión de realidades complejas, silenciamiento sobre aspectos importantes para la garantía de derechos, salud y denuncia de conflictos ambientales. Se concluye que la elaboración de estudios de impactos ambientales es una oportunidad para la práctica de la ecología de los saberes por medio de la producción de conocimientos compartida con los movimientos sociales, debiendo traducirse en instrumentos de defensa de la vida, con el objetivo de acciones de salud colectiva y de protección del ambiente...

Ação inovadora de enfermeira do trabalho: causas e custos do absenteísmo entre profissionais da saúde numa empresa petrolífera / Labor nurse's innovative action: causes and costs of absenteeism among health workers at an oil company

Tem-se como objeto do estudo a análise da ação inovadora da enfermeira do trabalho no controle do absenteísmo dos profissionais do setor de saúde onshore e offshore. O objetivo geral pretende avaliar as causas e o custo econômico direto do absenteísmo dos profissionais de saúde onshore e offshore, com base no percentual de tempo perdido registrado pela empresa, visando indicar medidas de prevenção do absenteísmo aos gestores da empresa do setor terciário, a partir da execução da ação inovadora da enfermeira do trabalho. Estudo de corte transversal, com análise documental, retrospectivo, com abordagem quantitativa, de caráter exploratório e descritivo, realizado numa empresa terceirizada que atua no setor petrolífero. Na estratégia de coletas de dados, foi realizado um levantamento estatístico sobre os profissionais de saúde, visando estabelecer o perfil econômico e funcional dos mesmos para caracterizar a população e amostra, que resultou em 59 e 43 profissionais de saúde, respectivamente. Os dados foram fornecidos pelo setor de recursos humanos da empresa com a aquiescência da direção que tem interesse no estudo. Usou-se um quadro demonstrativo para coleta dos dados. Foi utilizado o editor Microsoft Excel 2013 visando agrupar e calcular as variáveis numéricas. Através desse editor, foi feita uma análise quantitativa dos dados analisados e expostos em quadros, tabelas e gráficos para a demonstração dos dados levantados. Os resultados do estudo mostraram a importância da permanente ação inovadora da enfermeira do trabalho na sistematização dos registros de afastamento, no prontuário do trabalhador. Verificou-se que os profissionais que trabalham no ambiente offshore foram os que tiveram maior ocorrência de ausentismo.

This paper investigates labor nurse's innovative action controlling onshore and offshore absenteeism among health workers. It aims at evaluating both the causes and the immediate economic cost generated by health professionals' onshore and offshore absenteeism, on the basis of wasted time rates recorded by the company. It also aims at suggesting management in the service sector preventive measures by labor nurse's innovative action. Cross sectional retrospective document analysis, with qualitative, exploratory, and descriptive approach, conducted at an outsourced oil company. Data collection strategies included statistics on health workers to define their economic and functional profile as well as to characterize population and sample, resulting at 59 and 43 health professionals, respectively. Data were provided by Human Resources at the company, with Board of Directors' interest and consent. An exibition table was used for data collection. Microsoft Excel 2013 enabled grouping and calculating number variables. The same editor ensured data quantitative analysis, further fitted onto tables and charts for demonstration. Results show the relevance of the continuing and systematic innovative action by labor nurse onto attendance sheets on the workers' records. Higher absenteeism rates were also found among offshore professionals.

A efetividade de metodologias de diagnóstico rápido em ergonomia em plataformas offshore: revisitando o conceito de modo degradado de funcionamento / The effectiveness of rapid ergonomics diagnostic methodologies applied to offshore platforms: revisiting the concept of degraded mode of operation

Resumo Introdução: plataformas offshore enfrentam crescentes demandas de manutenção, com um quantitativo fixo de trabalhadores. Com o tempo, ocorre a degradação progressiva das instalações, sendo necessárias estratégias diferenciadas para recuperar a integridade operacional. Objetivo: apresentar como uma Metodologia de Diagnóstico Rápido (MDR) em ergonomia foi elaborada para avaliar um conjunto de plataformas e revisitar o conceito de Modo Degradado de Funcionamento, quanto a segurança e confiabilidade operacional. Método: a MDR foi construída em quatro etapas e aplicada em 12 plataformas. Para cada uma, foram retraçados os processos históricos de seu modo de operação atual. Resultados: esta MDR permitiu revelar princípios gerais para sistematizar situações que devem melhorar e compreender processos amplos, que levaram ao acúmulo de condições ergonomicamente inadequadas, e recuperar parte da experiência acumulada pelas equipes embarcadas. A chave foi a preparação para os embarques, baseada na experiência dos ergonomistas e dos trabalhadores onshore e offshore. Conclusão: diagnósticos rápidos podem contribuir para reverter processos crônicos de degradação ao revelarem a visão geral das condições de vida e trabalho a bordo, as trajetórias singulares das plataformas e a contribuição positiva dos trabalhadores, colocando em debate mudanças e ações necessárias à inflexão de um dado percurso.

Abstract Introduction: offshore platforms face increasing maintenance demands with fixed amount of workforce. Over time, the progressive deterioration of installations can be evidenced leading companies to adopt distinguished strategies to recover operational integrity. Objective: to present the development of a Rapid Ergonomics Diagnostic Methodology (REDM) to evaluate a group of platforms and revisit the concept of degraded mode of operation regarding safety and operational reliability. Method: the REDM was built in 4 stages and applied in 12 platforms of the studied company. For each one, the historical processes of its current operating mode were retraced. Results: this REDM allowed revealing general principles to systematize situations that should be improved, understanding broad processes that led to the accumulation of ergonomically inadequate conditions and recovering part of the experience accumulated by the embarked teams. The key was the preparation for shipments based on the ergonomics team and workers experience, both, onshore and offshore. Conclusion: REDMs can help to reverse chronic degradation processes by providing an overview of on boardwork and living conditions, the platforms’ unique trajectories and the positive workers’ contribution, discussing changes and necessary actions for a given route inflection.

Fatores de risco para absenteísmo com licença médica em trabalhadores da indústria de petróleo / Risk factors for absenteeism due to sick leave in the petroleum industry / Risk factors for absenteeism due to sick leave in the petroleum industryFactores de riesgo para el ausentismo con licencia médica en trabajadores de la industria del petróleo / Factores de riesgo para el ausentismo con licencia médica en trabajadores de la industria del petróleo

OBJETIVO : Identificar fatores de risco para o absenteísmo com licença médica em trabalhadores de empresa de petróleo. MÉTODOS : Estudo caso-controle (120 casos e 656 controles) aninhado a um estudo de coorte retrospectivo com todos os trabalhadores de uma empresa de petróleo na Região Norte-Nordeste do Brasil entre 2007 e 2009. A variável resposta utilizada para representar o absenteísmo com licença médica foi a incidência média de faltas com licenças médicas no período, definida pela razão entre o total de dias de licenças médicas e os dias potencialmente trabalháveis no período. Análise de regressão logística foi utilizada para investigar a associação entre incidência média de faltas > 5,0% no período e as variáveis sexo, cargo, idade, tempo de atuação, regime de trabalho, tabagismo, hipertensão arterial, índice de massa corporal, atividade física, risco coronariano, sono, glicemia, diabetes não controlado, doença do aparelho cardiovascular, digestivo, aparelho locomotor, neurológica, neoplasia, posturas forçadas no trabalho, satisfação com o trabalho, relacionamento com a chefia e atenção concentrada no trabalho. RESULTADOS : A incidência média de faltas com licenças médicas > 5,0% no período da coorte foi 15,5%. O modelo logístico revelou que trabalhadores com incidência média de faltas > 5,0% tiveram 2,6 vezes mais chance de ser do sexo feminino; 2,0 vezes mais chance de ser fumante; 1,8 vez mais chance de ser ex-fumante, 2,2 vezes mais chance de relatar sono anormal e 10,5 vezes mais chance de estarem insatisfeitos com o trabalho do que trabalhadores com incidência média de faltas ≤ 5,0% no período. CONCLUSÕES : Sexo feminino, ser fumante ...

OBJECTIVE : To identify risk factors for absenteeism among workers with sick leave in an oil company. METHODS : A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. RESULTS : Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. CONCLUSIONS : In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. .

OBJECTIVE : To identify risk factors for absenteeism among workers with sick leave in an oil company. METHODS : A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. RESULTS : Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. CONCLUSIONS : In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. .

OBJETIVO : Identificar factores de riesgo para el ausentismo con licencia médica en trabajadores de empresa del petróleo. MÉTODOS : Estudio caso-control (120 casos y 656 controles) anidado en una cohorte retrospectiva con todos los trabajadores de una empresa de petróleo en la Región Norte-Nordeste de Brasil entre 2007 y 2009. La variable respuesta utilizada para representar el ausentismo con licencia médica fue la incidencia promedio de faltas con licencias médicas durante el período, definida por el cociente entre el total de días de licencias médicas y los días potencialmente trabajables. Se utilizó análisis de regresión logística para investigar la asociación entre incidencia promedio de faltas > 5,0% en el período y las variables sexo, cargo, edad, tiempo de actuación, régimen de trabajo, tabaquismo, hipertensión arterial, índice de masa corporal, actividad física, riesgo coronario, sueño, glicemia, diabetes no controlada, enfermedad del aparato cardiovascular, digestivo, aparato locomotor, neurológica, neoplasia, posturas forzadas en el trabajo, satisfacción con el trabajo, relacionamiento con el jefe y atención concentrada en el trabajo. RESULTADOS : La incidencia promedio de faltas con licencias médicas > 5,0% en el período de la cohorte fue de 15,5%. El modelo logístico reveló que trabajadores con incidencia promedio de faltas > 5,0% tuvieron 2,6 veces más chance de ser del sexo femenino; 2,0 veces más chances de ser fumador; 1,9 veces más chance de ser ex-fumador; 2,1 veces más chance de relatar sueño anormal y 10,5 veces más chances de estar insatisfechos con el trabajo, en comparación con los trabajadores con incidencia promedio de faltas < 5,0% en el período. CONCLUSIONES : Sexo femenino, ser fumador o ex-fumador, estar ...

Indicadores de absenteísmo e diagnósticos associados às licenças médicas de trabalhadores da área de serviços de uma indústria de petróleo / Absenteeism indicators and diagnosis associated to sick leave among workers of the administrative service area of a petroleum industry

OBJETIVOS: Determinar indicadores do absenteísmo por licença médica (LM) em trabalhadores da área de serviços de uma indústria de petróleo, identificando as patologias associadas. MÉTODOS: Este estudo descreve resultados de estudo coorte retrospectivo com 782 trabalhadores de uma empresa de petróleo no período de 1º de janeiro de 2007 a 31 de dezembro de 2009. RESULTADOS: 542 trabalhadores tiveram eventos de faltas ao trabalho que geraram licença médica. Registrou-se 3,3 episódios de LM por trabalhador e 69,3% dos trabalhadores tiveram pelo menos um episódio de LM. Os episódios de LM duraram em média 6,6 dias, com desvio padrão de 9,8 dias. A maior proporção de episódios de absenteísmo por LM deveu-se às doenças do sistema osteomuscular e tecido conjuntivo. Dezesseis dentre os 782 trabalhadores apresentaram 17 episódios de LM associadas ao trabalho (acidente típico, de trajeto e doença ocupacional). CONCLUSÕES: O estudo ratificou a importância do afastamento por doenças do sistema osteomuscular e o impacto das doenças ocupacionais no absenteísmo por licença médica, detectando índices semelhantes ao da literatura, numa população pouco explorada do ponto de vista epidemiológico.

OBJECTIVE: To determine indices of sick leave (SL) absenteeism among workers in the administrative service area of a petroleum industry and to identify associated pathologies. METHODS: The study describes results of a retrospective cohort study involving 782 workers from an oil company, who were followed up from January 1, 2007 to December 31, 2009. RESULTS: During the study period, 542 workers reported SL events with physician's statements. An average of 3.3 SL absences per worker was recorded, and 69.3% of the workers had gone through at least one SL episode. SL episodes lasted in average for 6.6 days, with a standard deviation of 9.8 days. Most of SL absences were due to musculoskeletal and connective tissue disorders. Sixteen out of the 782 workers went through 17 work-related SL episodes (worksite accidents, commuting accidents and occupational illnesses). CONCLUSIONS: The study confirmed that musculoskeletal and connective tissue diseases are the most recurrent causes of sick leave absenteeism. The rates of absenteeism due to SL, in this population yet rarely investigated from the epidemiological point of view, were similar to those described in literature.

Gestão do trabalho na perfuração de poços de petróleo: usos de si e 'a vida por toda a vida' / Management of labor in the drilling of oil wells: uses of itself 'give life for all life'

Destacam-se no artigo os riscos potenciais à segurança e à saúde (especialmente a dimensão mental), associados às características do processo de trabalho e ao modelo de gestão do trabalho adotado pela empresa multinacional Schlumberger. Esses dois elementos aliados aos traços predominantes da indústria petrolífera tendem a expor seus trabalhadores a um aumento do custo psíquico (cognitivo, afetivo) em sua integridade biopsíquica (corpo-si). Indicam-se pistas para reflexão relativas à constatação das inadequações da organização do trabalho e do despreparo de muitos trabalhadores para lidarem com a intensidade das 'dramáticas do uso de si'. Questionam-se o alcance do 'sofrimento patogênico' presente na organização do trabalho, o comprometimento da possibilidade de sublimação e a possível conversão do sofrimento em criatividade (condição de 'possibilidade de circulações'). O referencial teórico-metodológico privilegia a ergonomia da atividade e a psicodinâmica do trabalho numa perspectiva ergológica. Os métodos operacionalizam um dispositivo dinâmico a três polos (DD3P) em 'encontros sobre o trabalho' e entrevistas semiestruturadas que valorizam a dialogia.

The article emphasizes the potentials dangers to the security and to the health (especially the mind ones), associated to the quality of work's process and to the standard of management work used by the Schlumberger multinational company. Both of these components associated to the main aspects of the petroleum industry tend to endanger its workers to increase their psychological costs (cognitive, affective) in their biopsychical (body itself) integrality. Trails denote the inappropriate workers structure and their despair to deal with the intensity of the 'use of itself drama'. The reach of 'pathogenic suffering' on workers structure, the compromising with the possibility of sublimation and the possibility to transform suffering on creativity (condition of 'possibility circulations') is argued. The theoretic and methodological reference emphasizes the activity's ergonomic and the psychodynamics of work in a ergological perspective. The methods operationalize a dynamic device of three poles (DD3P) on 'meetings about work' and on interviews semi-structured which valorizes the recurrence.