RCAAP Repository

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

Universidade Federal do Triângulo Mineiro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

n the last year the Petrobras Company gone self sufficiency of Brazil in the production of petroleum, It s take great effort to achieve technology in the exploration of deeper oil-well offshore. The extraction of petroleum deeper off-shore is make through flexible pipes that has multi layers of metal materials and polymeric materials, connected semi-submersible platform. This flexible pipes into contact with surface marine, in the area of touchdown point (TDP), sufferable abrasive wear. Currently the flexible pipes, at the TDP, are protected with bi part sleeve made in elastomer of polyurethane. This type of polyurethane has shown high performance against abrasive wear, when compared another polymers materials. This work has the objective of optimize the performance of elastômeros of polyurethane against abrasion wear at the TDP. This optimization was carried through formulation of various combinations of isocyanate and poliol, raw material by production of elastomer of polyurethane, with addition of solid lubricant molybdenum disulfide in the half of formulation. The evaluation of the molybdenum disulfide in the polyurethane was carried through structural characterization. The mechanical properties of formulations were carried through standard test methods for tension, elongation, tear strength, hardness, and rebound resilience. The wear resistance of formulations was carried through standard test methods for abrasion resistance according to the DIN 53.516 and Simulator of Interaction Marine-Mechanical in Sleeve (SIMMC), that it was development to evaluate sufferable abrasive wear for flexible pipe. The formulation of high performance had been submitted hydrolysis in hydrostatic compressive test equipment with heating. A correlation was looked among the properties obtained in the mathematical model efficient in the theoretical reproduction of the abrasive wear produced by SIMMC. In the end of this work got two formulations with high performance against wear abrasion.

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Universidade Federal de Viçosa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Conselho Nacional de Desenvolvimento Científico e Tecnológico

During the clutch engagement manoeuvre, sliding contact occurs between the pair of clutch facings mounted on the friction disk and the counter faces belonging to the flywheel and the pressure plate. The materials used in the clutch have to ensure a smooth performance and friction coefficient that is sufficiently high and stable, thus providing regular and efficient rotation transmission. The development of friction materials requires a large number of tests to understand their tribological behaviour. Such development is highly empirical and involves a large number of repetitions between the tests. Durability tests using dynamometers are traditionally used to measure the wear life of the friction material used in automotive clutchs. However, these tests are long, relatively expensive and complex, because they require the construction of prototypes. This paper aims to find a correlation between wear mechanism and wear rates for the friction materials used in dry automotive clutches measured using both durability tests and a pin-on-disk sliding tribometer. Pin-on-disk sliding tests are shorter, simpler and cheaper. After the optimization of the tribological parameters, pin-on-disk sliding tests under constant normal load using a pin diameter of 13 mm reproduced with remarkable accuracy the traditional durability tests, although in the durability tests the load was cyclic and the diameter of the component was 200 mm.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior