Digital radiography for the inspection of weld seams of pipelines - better sensitivity

Conventional radiography, using industrial radiographic films, has its days numbered. Digital radiography, recently, has taken its place in various segments of products and services, such as medicine, aerospace, security, automotive, etc. As well as the technological trend, the digital technique has brought proven benefits in terms of productivity, sensitivity, the environment, tools for image treatment, cost reductions, etc. If the weld to be inspected is on a serried product, such as, for example, a pipe, the best option for the use of digital radiography is the plane detector, since its use can reduce the length of the inspection cycle due to its high degree of automation. This work tested welded joints produced with the submerged arc process, which were specially prepared in such a way that it shows small artificial cracks, which served as the basis forcomparing the sensitivity levels of the techniques involved. After carrying out the various experiments, the digital meth odshowed the highest sensitivity for the image quality indicator (IQI) of the wire and also in terms of detecting small discontinuities, indicating that the use of digital radiography using the plane detector had advantages over the conventional technique (Moreira et al. Digital radiography, the use of plane detectors for the inspection of welds in oil pipes and gas pipes.9th COTEQ and XXV National Testing Congress for Non Destructive Testing and Inspection; Salvador, Bahia, Brazil and Bavendiek et al. New digital radiography procedure exceeds film sensitivity considerably in aerospace applications. ECNDT; 2006; Berlin). The works were carried out on the basis of the specifications for oil and gas pipelines, API 5L 2004 edition (American Petroleum Institute. API 5L: specification for line pipe. 4th ed. p. 155; 2004) and ISO 3183 2007 edition (International Organization for Standardization, ISO 3183. Petroleum and gas industries - steel pipes for pi pelines transportation systems. p. 143; 2007). © 2010 Taylor & Francis.

IMPACTOS AMBIENTAIS DECORRENTES DE VAZAMENTO DE GÁS NATURAL DE BAIXA E MÉDIA PRESSÕES, NA ÁREA URBANA CENTRAL DO MUNICÍPIO DE SÃO PAULO

Com a busca por fontes de energia alternativas, o gás natural vem adquirindo posicionamento de destaque por seu relativo baixo custo de aquisição ao consumidor final e por apresentar reduzidos impactos na implantação de dutovias, comparados com outras fontes de energia (hidroelétrica e fissão). O presente trabalho foi direcionado para a verificação de possíveis impactos oriundos de vazamentos em tubulações de gás em sua fase operacional. A área de estudo localiza-se no Município de São Paulo; sua escolha deve-se por apresentar tubulações centenárias que demandam constantes intervenções ou manutenções e pela fácil captação de amostras para análise. Foram amostrados 40 pontos e nestes analisados aspectos dos meios antrópico, biótico e físico-químico. O método adotado fundamentou-se na caracterização dos dutos de gás e sua manutenção, no diagnóstico ambiental, considerados os fatores ambientais solo, ar, flora, fauna, condições de vida da população e paisagem urbana, e posterior identificação de impactos, nas situações de alteração dos impactos ambientais. Os resultados demonstraram que qualquer vazamento de gás gera uma alteração em pelo menos um fator ambiental, denotando um impacto. Novas linhas de estudo são propostas como melhor análise químico-física do material exposto ao contaminante e reações químicas do odorante com o solo que teve contato.

Dutovias: aspectos gerais e a questão ambiental na definição de trajetos terrestres

Taking into account the consistent and important expansion of the Brazilian oil and gas pipelines network in the last years, this work discusses how these lines are planned regarding the continental environmental context. Its central objective is to show how studies to select alternative lines are made before a gas or oil pipeline is installed. These studies help to choose routes in which the environment is less affected by the pipeline, and use specific methods, technologies, and tools. Bibliographical studies combined with interviews and discussions with experts of the oil and gas sector were used to support this monograph.

Caracterização microestrutural de junta soldada com arco submerso e análise da propagação de trincas em um tubo de aço API X 70

In this work a study of an API 5L X70 steel, which is used in the manufacture of oil and gas pipelines, has been made. This class of steel show high strength and ductility values, and has been increasingly studied due the growing demand of oil and natural gas, which in consequence, increases the needing of new pipelines to transport them. The material studied has been directly taken from a tube provided by TenarisConfab, and a special attention has been given to the fatigue crack growth rate study, which proved that a crack will grow at different rates according to the tube position where it is growing

Estudo do efeito Bauschinger em tubos de aço API 5l x70 aplicados no transporte de petróleo e gás

Despite the growing concern in seeking more sustainable energy sources, oil demand is likely to grow in coming years. To keep up with this growth, the oil industry has increasingly invested in innovation and efficiency. Knowing that, new technologies have been developed to explore deeper waters, without giving up the best practices in worldwide operational safety. The use of rigid pipelines in deepwater offshore facilities is increasing quickly and because of this, the ways of storing and launching pipe have been studied and perfected. In this paper the Bauschinger effect on API 5L X70 steel was analyzed proving that there was a reduction in yield strength when an effort was applied in a previous direction, then an effort was then applied in the opposite direction. To observe this phenomenon, the tensile test was conducted to determine the mechanical properties of the base metal, such as yield stress, tensile strength, elasticity and maximum tensile, so then compare it with the results obtained in the Bauschinger Effect Test. The analysis results showed that the steel had high resistance, with good plastic deformation capacity without failing, well-defined yield point, showing itself appropriate for the operation of oil and gas pipes

Digital radiography using digital detector arrays fulfills critical applications for offshore pipelines

Digital radiography in the inspection of welded pipes to be installed under deep water offshore gas and oil pipelines, like a presalt in Brazil, in the paper has been investigated. The aim is to use digital radiography for nondestructive testing of welds as it is already in use in the medical, aerospace, security, automotive, and petrochemical sectors. Among the current options, the DDA (Digital Detector Array) is considered as one of the best solutions to replace industrial films, as well as to increase the sensitivity to reduce the inspection cycle time. This paper shows the results of this new technique, comparing it to radiography with industrial films systems. In this paper, 20 test specimens of longitudinal welded pipe joints, specially prepared with artificial defects like cracks, lack of fusion, lack of penetration, and porosities and slag inclusions with varying dimensions and in 06 different base metal wall thicknesses, were tested and a comparison of the techniques was made. These experiments verified the purposed rules for parameter definitions and selections to control the required digital radiographic image quality as described in the draft international standard ISO/DIS 10893-7. This draft is first standard establishing the parameters for digital radiography on weld seam of welded steel pipes for pressure purposes to be used on gas and oil pipelines.