Desenvolvimento de tubulação em compósito polimérico revestida externamente com poliuretano de alta densidade

Pipelines for the transport of crude oil from the production wells to the collecting stations are named production lines . These pipes are subjected to chemical and electrochemical corrosion according to the environment and the type of petroleum transported. Some of these lines, depending upon the composition of the fluid produced, may leak within less than one year of operation due to internal corrosion. This work aims at the development of composite pipes with an external protecting layer of high density polyurethane for use in production lines of onshore oil wells, meeting operational requirements. The pipes were manufactured using glass fibers, epoxy resin, polyester resin, quartz sand and high density polyurethane. The pipes were produced by filament winding with the deposition of high density polyurethane on the external surface and threaded ends (API 15 HR/PM-VII). Three types of pipes were manufactured: glass/epoxy, glass/epoxy with an external polyurethane layer and glass/epoxy with an intermediate layer of glass fiber, polyester, sand and with an external polyurethane layer. The three samples were characterized by Scanning Electronic Microscopy (SEM) and for the determination of constituent content. In addition, the following tests were conducted: hydrostatic test, instant rupture, shorttime failure pressure, Gardner impact, transverse stiffness and axial tension. Field tests were conducted in Mossoró RN (BRAZIL), where 1,677 meters of piping were used. The tests results of the three types of pipes were compared in two events: after two months from manufacturing of the samples and after nine months of field application. The results indicate that the glass/epoxy pipes with an intermediate layer of fiber glass composite, polyester e sand and with an external layer of high density polyurethane showed superior properties as compared to the other two and met the requirements of pressure class, axial tensile strength, transverse stiffness, impact and environmental conditions, for onshore applications as production lines

Tubulações de PRFV com adição de areia quartzosa visando sua aplicação na indústria do petróleo

Fillers are often added in composites to enhance performance and/or to reduce cost. Fiberglass pipes must meet performance requirements and industrial sand is frequently added for the pipe to be cost competitive. The sand is added to increase pipe wall thickness, thus increase pipe stiffness. The main goal of the present work is to conduct an experimental investigation between pipes fabricated with and without de addition of sand, to be used in the petroleum industry. Pipes were built using E-glass fibers, polyester resin and siliceous sand. The fabrication process used hand lay up and filament winding and was divided in two different parts: the liner and the structural wall. All tested pipes had the same liner, but different structural wall composition, which is the layer where siliceous sand may be added or not. The comparative investigation was developed considering the results of longitudinal tensile tests, hoop tensile tests, hydrostatic pressure leak tests and parallel-plate loading stiffness tests. SEM was used to analyze if the sand caused any damage to the glass fibers, during the fabrication process, because of the fiber-sand contact. The procedure was also used to verify the composite conditions after the hydrostatic pressure leak test. The results proved that the addition of siliceous sand reduced the leak pressure in about 17 %. In the other hand, this loss in pressure was compensated by a stiffness increment of more than 380 %. MEV analyses show that it is possible to find damage on the fiber-sand contact, but on a very small amount. On most cases, the contact occurs without damage evidences. In summary, the addition of sand filler represented a 27.8 % of cost reduction, when compared to a pipe designed with glass fiber and resin only. This cost reduction combined to the good mechanical tests results make siliceous sand filler suitable for fiberglass pressure pipes

Sujeitos e atores sociais nas representações discursivas de docentes da rede estadual de ensino em Sergipe: uma análise crítica em tempos de Ideb

According to the studies in Applied Linguistics, this thesis is based on an interdisciplinary perspective (Critical Discourse Analysis, Sociology towards Social Change, Cultural Studies and Systemic-Functional Linguistics). The overall objective of the research was to analyze the discourses of Elementary School teachers in the state of Sergipe, by means of the discursive representations of the social actors, the processes of subjectivity and their fragmented identities in the context of standardized evaluations before the requirements of globalized pedagogical practices, based on the result-based management. The critical analysis of such discourses was motivated by the rapid pace with which the demands of innovation become part of the classroom, aiming at reaching the target in what concerns the indexes of the rankings which characterize the globalized discourse of the national education management, like Ideb (Basic Education Development Index), which makes teachers change their discourses, become silent or keep resistant. The work was initially endorsed by the theoretical lines of the Critical Discourse Analysis (FAIRCLOUGH, 2001, 2006), and poses a proposal for such purpose: the ASCD Discourse Sociological and Communicative Approach (PEDROSA, 2012, 2013). This is an interpretative-qualitative study of the Critical Discourse Analysis (FAIRCLOUGH, 2001, 2003; RAMALHO ; RESENDE, 2011) and to carry it out, semi-structured interviews were used as instruments of data generation (BAUER; GASKELL, 2011; GILL, 2011). Its corpus is composed of thirteen accounts of teachers from the Elementary school who teach Portuguese and work in the fifteen schools which were chosen to be the universe of the research at the Regional Board of Education (02) in the state of Sergipe. Such narratives are related to their impressions, expectations and actions which favor the management of results to which they have to submit themselves. The analytical overview of sociological and discursive line comes from the pan-semiotic categories (Inclusion and Exclusion) which appear in the theory of Representation of Social Actors (VAN LEEUWEN, 1997, 2008). To present the processes of subjectivity of these teachers, this work is based on the socio-analytical proposal of the classification of the subjects, which stems from the individual s work in the Gestão Relacional de Si , which comes from the Applied Sociology (towards) Social Change (BAJOIT, 2006, 2009). The discursive analyses were guided word for word, in their majority, by having the Systemic Functional Grammar as their theoretical basis, specifically by the processes of the Transitivity System postulated by Halliday, (1985); Halliday and Mathiessen, (2004); Eggins (2004); Cunha and Souza (2011). The work makes the field of Cultural Studies emerge towards the dialogue and the presentation of the fragmented identities of the teachers in the context of late modernity (GIDDENS, 2002; HALL, 2011). The thesis promoted a reflection over the teacher s condition, who is immerse in this context of knowledge construction of the present Brazilian educational system, the standardized evaluations, the indexes of development, the targets and the rankings. The considerations and outcomes of such a research dealt with the teachers emerging social practices and the need of planned initial and continuing teacher education towards the new moment which is foreseeable

Adolescentes preocupadas em conquistar um corpo magro: Um estudo sobre discursos produzidos em diários eletrônicos

The concern about a good physical condition is heavily present nowadays, in documentary films about health and in the media, and it is also expressed through the outstanding growth of physical academies, beauty institutes and aesthetic medicine and all kind of aesthetic surgeries. In the western world the body wave is a significant trend, characterized by the great investments in body image. However, what is overlooked is the fact that in parallel trend grows the number of teenagers, especially females, with all kind of problems related to their body image. As adolescence is a moment of transformations, teenagers tend to be more aware of their body image and often neglect food ingestion and try to build their bodies following the images they have from top models and movie stars. The low self-esteem accompanying this sort of experience is an additional problem. Therefore the research aim to analyze discourses regarding the body image produced in world wide web diaries (blogs). The blogs selection was made through the site www.blogs.com.br, which is considered the widest guide of electronic diaries in Brazil. We looked after blogs including the keyword body and from adolescents aged 10 to 19, who showed concern about a slim body. Three blogs were chosen, considering the example criteria. Discourse analysis shows that these teenagers feel unsatisfied with their bodies, searching by all means the thinness presented as a aesthetic paradigm in western societies which often implies neglecting their own health, using appetite inhibitor drugs, restricting or totally abstaining food ingestion for long periods of time, or provoking themselves vomits after ingesting food. These behaviors, together with intense fear of gaining weight, can be characterized as alimentary disorders, related to the body image. As they usually hide this sort of behaviors from family and friends who do not share this concern, the blogs seem to be an easy tool for adolescents to find peers with whom to share common values and ideas and reaffirm their identities and virtual sense of community