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A damper and a gas spring being a thermo engine which vibrational energy absorption occurs over heat transformation, requires very specific properties of thermo chemical stability from the hydraulic fluid as well as shear strength by heat and pressure effect. It competes to the hydraulic fluid the task of this transformation vehicle. The absorption performance of a damper depends on variation of physical-chemical properties of the hydraulic fluid under heat effect and the maintenance of this performance depends on conservation of those properties during time. The traditional hydraulic fluids for this application, despite its thermo-chemical stability, suffer a deterioration process of those properties under severe operating conditions and consequently reflect in the damper component lifetime.

The commercialization of additives for treating internal combustion engine oils in Brazil was regulated by ANP Ordinance n° 131, from 30.7.1999 and revoked by ANP Resolution n° 10, from 07.03.2007, where requires the performance proof of the referred additive following the ASTM Sequence IIIF bench engine test. The test PB/IMI-1109S3FGM151-2 establishes a procedure to evaluate internal combustion engine oils as well as additives against special performance conditions particularly operating at high temperature based on ASTM D 6984-09 Sequence IIIF procedure. This test measures oil thickening, sludge and varnish formation in engine components, piston deposits, oil consumption and camshaft wear. The ASTM procedure also suggests the use of any engine that proves the competence to accelerate thermochemical deterioration of lubricants under severe operating conditions and temperature, allowing in that way the development of this test procedure.

Metal in general presents two distinct regions in tension by deformation curves, one elastic and other plastic. At the elastic region, there is a direct proportionality between applied load and correspondent deformation. This can be called an elastic linear behavior of the material. Considering graphite content cast iron with lamellar morphology this behavior does not follow the same pattern. Since the beginning of the loading those materials present non-linear behavior with the load applied. In this report will be presented microstructure analysis, micro and macro hardness tests and a precise determination of tension versus deformation curves of perlitic gray cast iron with predominant Type A graphite to get the real tension profile developed when flexion loads are applied.

Seeking for technologies to meet uprising environmental legislation restrictions all over the world, the use of EGR valves [1] in Heavy Duty Diesel engines seems to be irreversible and so frightening. Despite its notable contribution to Nitrogen Oxides emission reduction, its catastrophic effects on accelerated corrosive wear in liners and piston rings are very well known by the industry. For EGR valves with condensation technology this undesirable effect is substantiated with fuel sulphur content and acids produced by combustion, a characteristic still present in fuels commercialized in Brazil. This report presents the performance of a bench engine test procedure for heavy duty Diesel that provokes accelerated polish of liners and piston rings by corrosive and abrasive wear in a short period of running test when compared with standard industry procedures for wear and durability evaluation.

Serviço Estendido ou Serviço Extremo! Pesado investimento no setor automotivo tem sido aplicado no desenvolvimento de tecnologias para prolongar o intervalo de serviço e melhorar eficiência trazendo vantagem competitiva para fabricantes e consumidores. Novas tecnologias de Motores, mais eficientes e menos poluentes com maiores reservatórios de óleo, combustíveis mais limpos com combustão mais controlada, lubrificantes com tecnologias de dispersãncia/detergência inimagináveis. Mas nada seria tão radical quanto sugerir 500.000 km ou 4.000 horas rodadas sem troca de óleo. Este é o desafio final prometido para o sistema de gerenciamento contínuo de óleo desenvolvido e patenteado pela Cummins Inc. em 1997, um novo conceito em troca inteligente do óleo do motor pela sua contínua substituição, sem paradas.