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This paper intends to make some preliminary considerations in the automobile life cycle, this is, from the extraction to the disposal of the material. First of all, a short introduction about the growth of the automotive fleet since past times and its perspectives for now on are presented. It is given a brief description of the life cycle analysis tool, on which the considerations of this study are based, of the aluminum used in automobiles. Due to the lack of data, this study is limited to the verification of developed countries cases and to some stages of the life cycle. When considering energy consumption, there are some immediate preferences concerning a specific stage, when considering other impacts, however, the choice becomes more difficult. This allows the conclusion that the delimitation of impacts in the analysis may lead to results not always implying on the improvement of environmental matters.

In the engineering structural analysis, one of the most important procedures is the definition of the mathematical model that, under certain hypotheses, appropriately represents the real problem. Then, the model can be evaluated in structural analysis programs, like those based on finite elements, for example. The Finite Element Method is a numeric procedure and, obviously, the answers are reflexes of the adopted hypotheses. To predict the answer of a physical problem in a satisfactory and reliable way, it is necessary to establish other complex models and to choose, among them, the most appropriate. In this paper, the applicable hierarchical models to a piping are discussed. The conclusions will be the basis for conception and analysis procedures of a tubular vehicular structure “off-road.”

Heavy lorries and trailer combinations cause many serious traffic accidents. Improvements in inspection methods of brake systems increase traffic safety. In Finland dynamometer measurements have been used since 1960's, and its advantages are stable measuring conditions, high repetability and short inspection time. Braking force on the wheel periphery generated by the wheel brakes is measured in the roll set of the dynamometer with the help of a power measurement device connected to it. In the vehicle inspection and in the brake repair shops, the estimation of the braking ability of vehicles based on calculated definitions of the performance of the brakes and the retardations to be achieved carried out on the basis of braking forces measured with the dynamometer. The Finnish Ministry of Transport and Communications and the

This study registers a finite element analysis of a seal boot used in constant velocity driveshafts. By this analysis the structure's behavior is studied in its work life before construction of the actual prototype. Prototype development time can be saved in the design phase since the part can be improved by this theoretical prediction tool. Failure points are predicted by the analysis saving resources such as developing production tools, making prototypes and testing them to finally detect the items that have to be improved. Analysis are made regarding an existing seal rubber boot. Then the results of general part are examined and contrasted with laboratory test reports of the real part.

The objective of this work is to provide the engineering department with a simple and useful tool to predict the valve pieces to be used in a shock absorber during the design phase, in order to diminish the experimental work to be done during the vehicle ride test and prototype manufacturing. This tool is a group of equations that can predict the force behavior of the shock absorber and the corresponding valves according to the preliminary shock absorber force x velocity curve defined by the vehicle suspension engineers.

The paper will detail the construction of the overall CVCP system, and the components. The emphasis will be on the phaser construction. The phaser is designed to provide extended durability (minimized spline stress, active lash compensation), simplifed manufacture and assembly, minimized package size (diameter & length), and good dynamic stability. The discussion of the overall CVCP system will include control valve geometry, and oil passages from the oil pump to the phaser. The paper will then discuss the different applications of VCP, and the advantages of each in terms of idle stability, torque, emissions (NOx & HC), and fuel economy.

Some problems that will be encountered with research and development in the automotive industry can already be foreseen today. New and more stringent standards as well as the market itself constantly put new demands to the scope of engine and vehicles available. Increased use of dynamic and transient test stands helps reduction of development times because they enable development testing already at times where only vehicle components are available. Special testing equipment is, however, required for dynamic and transient test stands. The ranges of application and system prerequisites for dynamic engine test stands also including transient test stands will be described hereafter. These test stands should rather have a modular structure with standardized interfaces to enable adaption to new testing tasks. Integration of the best devices available in the market into an existing test stand should be possible without any problem.

The diamond thin films chemical vapor deposition (CVD) on sintered tungsten carbide (WC-Co) tools shows increasing interest in the technological research, due to rapid growing utilization of aluminum alloys, like Al-Si alloys, in the automotive industry. Sintered carbides, mainly diamond coated sintered carbides, are very suitable to machine aluminum alloys. The cobalt binder that accounts for the WC-Co substrate toughness degrades the interface film-substrate, catalyzing the formation of graphite preferentially to diamond during the deposition process. In addition, stresses are generated in the interface between WC-Co substrate and deposited diamond film due to thermal expansion mismatch. These two factors are a technological neck to large-scale production of diamond CVD coatings for machining tools. In this work, several interface pre-treatments were developed and applied resulting in high film-substrate adherence, adequate for machining tool purposes.

Once microprocessor technology is introduced, a new world of opportunities becomes available to the automotive designer. Electronics opens the way for new approaches to systems management, driver information, collision avoidance and active controls that were not possible before. Besides that, a considerable fraction of today's vehicles are now equipped with telephones and navigation units are joining. In the next couple of years TV, video and multi-media PC will have increasing use in vehicles. The challenge for the electrical system designer is to find a medium which can support the data transfer required by such applications while maintaining electromagnetic compatibility with all other vehicle systems. This study discusses the importance of fiber optics ( more specifically Plastic Optical Fiber - POF ) to achieve these requirements.

The use of alternating current machines of a simple construction with the squirrel cage rotor or the soft iron salient pole rotor as a car generator allows to increase a reliability of a generator and the maximum rotor rotation frequency as well in comparison with synchronous machines. The main feature of a car generator operation is a wide range of a rotation frequency change (five or six times). The use of alternating current machines aforementioned with the capacitor excitation is impossible, because it requires a capacitance value change in a wide range. In the paper presented the rotor excitation by passing current impulses through the stator winding over necessary periods of time is considered. The possibility of such an excitation is confirmed by the experiment. The single-phase generator with external rotor excitation is analysed on the basis of a digital model.

This paper describes how Fluorescent Penetrant Inspection (FPI) was used in the past, how it is used now and how it will be used in the future. The United States Air Force (USAF) and Pratt & Whitney (P&W) now use a fully-automated FPI process with manual visual inspection. With direction and funding provided by the USAF/Aeronautical System Center (ASC), these fully-automated FPI processors, located at Kelly Air Force Base in San Antonio, Texas were developed, manufactured, installed, qualified and put into operation by Pratt & Whitney. This paper will cover the following: the Qualification and Acceptance Tests which include test objectives, test articles, test facility, test equipment, test results, and training.

In the aircraft industry's continual effort to select materials that meet the varied environmental regulations, Boeing has taken on the challenge of addressing the regulations and at the same time providing the airlines with functional alternatives. A mission was undertaken to provide the airlines with a flexible means to comply with their individual local environmental regulations, especially as they relate to solvent applications. This has been accomplished through the use of the aircraft maintenance and repair manuals, allowing each individual airline to link each specific solvent cleaning process to a “solvent series identification” that represents a solvent of their choosing from a list.

Sandblasting, high-pressure water jet, thermal and chemical treatments and other paint removal methods expose the surrounding environment to atmospheric hazards due to the resulting dust, dispersed liquid particles, ash and fumes. The prime objective of this article is to describe how thermal spray technique could provide an environmentally-friendly cleaning and removal process. A second objective is to discuss results obtained by using the Dual Torch Plasma System (DTPS) for de-painting of aluminum substrates. It was shown that the high traverse speed of the DTPS prevents the appearance of mechanical stresses in aluminum alloy structures as thin as approximately 1.5 mm. A CMC repair and titanium welding using DTPS are also discussed.

The rapidly increasing use of composites on commercial airplanes coupled with the potential for economic savings associated with their use in aircraft structures means that the demand for composite materials technology will continue to increase. Inspecting these composite structures is a critical element in assuring their continued airworthiness. The FAA's Airworthiness Assurance NDI Validation Center, in conjunction with the Commercial Aircraft Composite Repair Committee, is developing a set of composite reference standards to be used in NDT equipment calibration for accomplishment of damage assessment and post-repair inspection of all commercial aircraft composites. In this program, a series of NDI tests on a matrix of composite aircraft structures and prototype reference standards were completed in order to minimize the number of standards needed to carry out composite inspections on aircraft.

This presentation discusses the many rewards of establishing safety as a major criteria in selecting and managing the outside firms that perform aircraft maintenance and repair operations under contract. Whether the outsourced work is done on-site or at the contractor's location, fewer safety incidents among workers can result in better quality work and lower outsourcing costs. To demonstrate a successful program, the presentation reviews DuPont's award-winning approach to contractor safety which has helped the company improve profitability, increase shareholder value and enhance its public image. Six core elements that drive the company's contractor safety program are reviewed.

This paper primarily discusses two non-methylene chloride (and completely non-Hazardous Air Pollutant (non-HAPS)) paint removers. Specific areas discussed include test results, trial results and production results. The two paint removers are Stingray™ 853 and 874B. Stingray™ 876 is also discussed as it compares to 874B.

A study was conducted to develop and validate a Pressurized Water Stripping (PWS) process for use on aircraft and aircraft components to allow selective removal of the topcoat. By design, the process incorporates a barrier coating to encapsulate either the epoxy (MIL-P-23377) or polyurethane (TT-P-2760) primer used on military aircraft today. Then a water-only stripping process is used to remove the MIL-C-85285 polyurethane topcoat leaving the primer and barrier coatings intact. This system includes an inexpensive method for removing and reapplying the topcoat without disturbing the underlying primer or substrate. The barrier coating is designed to be resistant to moisture and erosion damage by the Pressurized Water Stripping process.

The paper describes aircraft maintenance research funded by the Federal Aviation Authority currently being pursued by Clemson University in cooperation with Lockheed Martin Aircraft Center and Delta Air Lines. The research describes how computer based training (for individual skills and team skills) is being used to improve the effectiveness and efficiency of aircraft maintenance operations.

The drive towards improved fuel economy and lower emissions for Diesel vehicles requires the development of catalysts capable of converting not only carbon monoxide (CO) and hydrocarbon (HC), but also particulate matter (PM) and nitrogen oxides (NOx) in a lean exhaust environment. This paper reviews the approaches that are being considered for this purpose, for light duty Diesels, together with factors that may influence catalyst performance such as components in the fuel and quality of the lubricant.

The Closed-Loop, Full Authority Lean Burn Control System provides an high accuracy control strategy made possible by using digital electronics and software technology that overcomes many difficulties encountered in the last few years. Using this technology we will be able to provide significant emissions integrity and protection against detonation caused by changing gas qualities.