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Nowadays, the cares with the vibration and the demands with the comfort of self-driven vehicles became basic requirements to the acceptance of a new truck market project more competitive and optimizing solutions that reduce the problems with vibration and comfort. Inside of those, an evaluation of commercial prototype vehicle of medium load will be presented in this work, searching to reduce a flaw still detected on test phase. Measures as change of shock cabin absorber, changes of tires, system of stabilizer bar at the back axis, changes of the front springs and use of linked shock absorber to the mount of the engine will be presented. Evaluations, which were done initially in the vehicle, the diagnosis was the movement happened due to resonance that includes the flexural of the frame, associated to the movement of pitch of the power train and of the cabin.

The aim of this work is to evaluate the mechanism of stock removal and the ground surface quality of advanced ceramics grounded by a plane tangential grinding process with diamond grinding wheels. The analysis of the grinding performance was done regarding the cutting surface wear behavior of the grinding wheel for ceramic workpieces. The discussion about the results emphasized the wear mechanism of the grinding wheel cutting surface and the cutting phenomenology of the grinding process. The grounded surface was evaluated using Scanning Electron Microscopy (SEM).

There are many advantages to air intake manifolds molded from Nylon 6,6 Glass reinforced composite material versus a pressure-cast aluminum manifold. Weight is significantly lowered and production costs generally are reduced. Performance improves with the precise control of the interior surface finish and reduced air induction temperatures. The Nylon 6,6 Glass reinforced composite material can be molded into intricate shapes by injection molding or lost-core process with reduced machining operations as well as Nylon 6,6 material is easily recycled. Production costs will continue to decrease as optimization of material, process and part integration increases. This study evaluates Nylon 6,6 Glass reinforced composite material in terms of the intake manifolds material key requirements such as thermal, heat aging, fatigue, impact, creep, stress and chemical resistance including multi fuels.

Based on the principles of the renown Toyota Production System, a new planning approach has been applied to a product development project at Mercedes-Benz do Brasil, Sao Paulo. The key elements are Master Process Sheets, which document assembly operations as agreed standard operations and hence assure continuously high, repeatable quality. Master Process Sheets visualize the assembly operations using explosion drawings and provide a much higher degree of understanding and information accessibility to production workers compared to earlier main-frame based process planning systems.

To predict the failure modes of a Diesel engine we have to use several condition monitoring techniques. Besides the trend analysis of engine performance parameters, the technique of lub oil condition monitoring is widely used for warning against failure in Diesel engines. It seeks to improve engine predictive maintenance by increasing availability, reliability, reducing maintenance cost and failures in operation. The technique presented in this paper entails a regular and periodic sampling of the engine lubricant oil followed by a laboratory analysis of its condition degradation and contamination. The analyzed data is then stored in a computerized data base for rapid manipulation and graphical retrieval to identify abnormal trends that characterizes the development of a future failure of engine component. Engine diagnosis is then presented by an Expert System.

This work deals with the natural weathering of PP composites containing weld lines. Single and double-gated injection molded bars were exposed to natural environment in Campina Grande (Brazil) for periods up to 45 weeks and they were tested for mechanical properties, surface fractography and IR spectroscopy. The results pointed that weld lines make the parts weaker, although the strength loss caused by weathering of double injected samples was similar to the ones produced by single-gated injection. It was also observed peculiar characteristics such as strength recovery after long term weathering and adhesion reduction of the glass fiber composites.

With the Xtend clutch a new concept for automatic wear compensation, which is suitable for push- and pull-type clutches of all sizes, has been developed. A very high level of accuracy of the adjusting process could be achieved under all operating conditions by the direct mechanical coupling to the wear of the clutch facings. It can be used without any changes to existing interfaces and possesses the same robustness and is as easy to handle as any conventional clutch.

The implementation of SDWT's ( Self Directed Work Teams ) requires a proper environment in which this management model can flourish and generate effective outcomes and, at the same time, be self sustained. The tools offered by the Learning Organization principles (1) mainly when one views the organization as a total System, allow for the setting of the conditions which will lead to a sustained environment that will allow the SDWT approach to be continuously successful and build upon itself, allowing for ongoing improvements. The implementation, hence, requires involvement from all levels in the organization, otherwise it may become another “flavor of the month” and it will be abandoned or it will not provide all the synergy for which it has potential. Rightly implemented it will generate outstanding and surprising results and it will set the stage for a continuous flow of creativity and innovation inside the organization.

This paper uses sets of experimental data, concerning commercial vehicles, to study the correlation between pass by and stationary noises through measurements executed according to external noise standards. We consider two sets of experimental data: before the new legislation (higher levels) and lower levels satisfying the new limits in Brazil. In addition we calculate the Loudness in sones, from the octave band noise spectrum, and compare the results with the usual evaluation in dB(A), with the purpose of emphasizing the qualification besides the quantification aspects and promoting conditions for people understanding. Besides the overall noise, we show the bandwidth contribution for each parameter and analyse the spectrum profile associated to the “A” weighting curve applications. The discussions, conclusions and recommendations are supported by regression curves and graphics taken from the measurements effectuated involving the chosen parameters.

Servo-hydraulic test systems are used to apply precise loads and displacements to specimens as part of a program of evaluation in the laboratory. For the test system to correctly load the specimen the type of servohydraulic control must be carefully selected. Factors such as accuracy, repeatability, control range and stability depend on the matching of the control scheme to the characteristics of the test stand, specimen and the command profile. This paper reviews the compensation methods available with particular reference to practical applications of the different methods in the laboratory testing of automobiles from components of all types through sub-systems to full vehicles.

This paper describes the applicability of genetic algorithms on route optimization with the objective of evaluating its potentialities comparing to other most used techniques. A classical mathematical problem known as Travelling Salesman Problem was used to create the scenery of a given problem that had to be optimized. At the end, the simulation results of a program that operates with genetic algorithms will be compared with the most useful heuristics algorithms.

This article is intended to propose the utilization of performance measures and models as an alternative to usual reliability analysis. The usage of such models is an important technique, specially on applications in which the time available to test a new product is rather reduced and the traditional life tests provide little or no failure at all. Performance data modeling allows that the failure, and the distribution of failure time, be anticipated even when no failure is evidenced in the testing unit. The utilization of these models is portrayed by modeling an automotive component (universal joint), and by studying the correlation between a universal joint performance in lab tests and in field tests.

The lower temperatures encountered with European Stage III/IV turbo charged direct injection (DI) Diesel engines with additional features such as cooled exhaust gas recirculation (EGR), compared to Stage II engines, means that modern light duty Diesel engine exhaust gas will rarely exceed temperatures of around 550° - 650°C under full load conditions, and under normal driving conditions, temperatures as low as 120°C will be common. The development of high activity Diesel oxidation catalysts (DOCs) having good low temperature performance is therefore key for achieving hydrocarbon (HC) and carbon monoxide (CO) conversions to meet Stage III and IV legislation. It is shown that extended operation of conventional DOC technology, at the lower temperatures encountered on modern Diesel engines, introduces an important mechanism of catalyst deactivation by accumulation of soot/coke and associated sulfur.

Sheet metal forming processes are increasingly focused on tribological parameters, and the sheet metal surface topography is nowadays a characteristic that show great potential for the process optimisation. In this paper, three different surface textures of an aluminium alloy AA 6016-T4 are characterised by 2D and 3D surface analysis methods. The effects of the surface topography on the friction behaviour and the formability were investigated by means a twist-compression test and a deep-drawing test, respectively.

General Motors Corporation has always made every effort so that our end products and processes and configuration of components could help preserve the environment. Along those lines, General Motors do Brasil started to develop a protective coating that is corrosion resistant and environment friendly. At first, this will be used for fasteners. This effort involves dramatic changes in attitude, such as our need to admit that we are responsible for managing resources and keeping our world habitable and healthy for the future generations. This study describes metallic and organometallic coatings with an increased resistance to corrosion associated to temperature, free of such harmful metals as cadmium, nickel, lead, chromium, etc. Also demonstrated here is the significance of the total friction coefficient and its composition, considering the friction coefficients inherent to the fastener threads/heads.

The control of emissions from mobile sources continues to play an important part in air quality improvement. Future reductions in vehicle emissions are proposed or legislated in many countries throughout the world. The most stringent of these standards under discussion are those in the Californian LEV-II proposal, a part of which is the SULEV standard which requires a large reduction in hydrocarbon emissions, together with a significant decrease in NOx, over those legislated for ULEV. This requires the engine and aftertreatment system to deliver both a substantial reduction in the emissions of hydrocarbon during engine warm-up and increased NOx conversion during high speed operation, compared to previous ULEV systems. In this paper we outline three different catalyst systems which show the potential to provide reduction in vehicle emissions below the currently legislated ULEV and European Stage IV standards.

1 The present work describes the modeling and analysis processes of a medium sized truck manufactured in Brazil with regard to comfort behavior. The vehicle model includes Hotchkiss suspensions front and rear with shackle and with a double stage with bump stops at the rear. It is also included frame flexibility in ADAMS, the frame characteristics were imported from a Finite Element Analysis model. Nonlinear shock absorber curves are also represented for the vehicle and cab suspensions. Viscoelastic bushings for cab and powertrain suspension are also included. Random track profile is generated as input and vehicle comfort is described in terms of the ISO 2631-85 Standard. The effect on vehicle comfort of changing a design parameter can be predicted in the model and verified experimentally.

Project management has evolved with time but it does not happen in the same manner with the evolution of management and execution relationship, specially in the occidental World. The execution, constituted by the work level, plays an extremely important role and has a substantial participation in project development, i. m., establishes the cadence of the development. This proposal breaks with the traditional models and innovates them by taking the work level as the basis for the development, let the work run free and call them to participate in project development decisions, motivating the enthusiasm and their latent pro-activity. Any way, the proposed model is formed of two blocks, Management and Execution, this last one formed by PDTs (Product Development Teams), under the leadership of a single Project Manager.

Flash point is a key property in characterizing petroleum products. The standard ASTM D92 establishes a method for the measurement of flash points using both manual and automatic instruments. From 1993 to 1997, the Laboratory of Fuels and Lubricants of IPT has coordinated 15 interlaboratory comparison programs, using samples of several blends of mineral oils. This work presents and compares flash points obtained in those interlaboratory programs by means of manual and automatic instruments A consistent difference between flash points resulting from the two kinds of instruments was recognized and a correlation equation was derived.