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Counterfeit Electronic Parts: Supply Chains at Risk (DVD)

2015-04-15
"Spotlight on Design" features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Just how prevalent is the problem of counterfeit electronic parts? What are the consequences of using sub-par components in safety or mission critical systems? The Federal Aviation Administration estimates that 2% of the 26 million airline parts installed each year are counterfeit, accounting for more than 520,000 units, maybe more.
Technical Paper

Transmission Oil Degradation Warning Systems and Computing in Agricultural Tractors

2000-06-19
2000-01-1873
This communication examines three strategies of predictive lubricant monitoring and replacement, used for farm tractors or similar vehicles. These strategies optimise the draining periodicity. They are the off-line follow-up, the sensors follow-up and the analytical model follow-up. The implementation of the suggested analytical model will be discussed, on the basis of field collected data (on a series of tractors, either customer's or on loan). Regular oil samples, and significant ones carried out at the end of the study, were taken and analysed in order to predict the evolution of the lubricant characteristics. Extensions to the experimental study were carried out at the end of this work. They are discussed in the paper (FZG gear scuffing, 4 ball wear and EP…).
Technical Paper

Investigation of a Roll Control System for an Off-road Vehicle

2000-05-01
2000-01-1646
The current popularity of the Sport Utility Vehicle (SUV) market has led to new developments aiming to increase product performance. Such vehicles pose a significant challenge as they must perform to a high standard over a large variety of road conditions. Previously, emphasis has been placed on off-road ability. However, SUVs are now seen as an alternative to conventional luxury cars, and hence are expected to perform similarly, but without significantly degrading off-road performance. The introduction of a roll control system can achieve body roll levels lower than a conventional sports saloon, whilst improving off-road ability by removing the compromises associated with conventional anti-roll bars. This paper investigates the characteristics of such a system by developing a computer simulation of the vehicle and the associated roll control scheme.
Technical Paper

Investigation of Package Bearings to Improve Driveline Performance

2000-06-19
2000-01-1785
The tapered roller bearings employed in axle centers for the pinion support are critical components in determining the noise, fuel economy and reliability characteristics of the vehicle. They represent a relatively complex mechanical and tribological system, with special requirements from the stiffness, lubrication and heat transfer points of view. This paper brings a contribution to the investigation of the intricate dependency between design parameters, environmental factors and the resultant performance of a package bearing in an integral double cup configuration. Axial compactness, reduced weight, and superior rigidity are only few of the multiple advantages recommending this type of double row bearings for automotive driveline applications. Different aspects related to the tapered roller bearing setting are analyzed in a theoretical and experimental manner, also under the consideration of the manufacturing and assembly processes.
Technical Paper

Verification of Heavy Truck EBS and ABS Using MatrixX Hardware in the Loop Tools

1999-11-15
1999-01-3713
The development of advanced ABS, EBS, and vehicle dynamics control systems requires significant resources and testing. Even in the most controlled environment, on-track vehicle tests are not repeatable. A heavy vehicle model combined with pneumatic brake hardware connected to actual brake system controllers creates a powerful engineering tool. This tool is useful for control system development, electro-mechanical actuator development, and brake system development. An existing heavy vehicle model is modified to interact with the realtime simulation hardware and the pneumatic brake system hardware. Data from several hardware in the loop simulations are presented.
Technical Paper

Compressor Oil Carryover and Its Effect on the Pneumatic System

1999-11-15
1999-01-3768
Oil carryover is present in all pneumatic systems where the compressed air is generated by oil lubricated compressors. With the increased use of electronic and small orifice components on trucks and coaches, the problem of contamination and failure related to oil carryover in the compressed air system has increased. Even though the rate of oil carryover out of the compressor has improved over recent years, problems persist. This paper will describe how the oil is transported out of the compressor, the various states oil is generated including vapor pressure profiles and size distribution of the condensed aerosols. Also reviewed is the oil removal effectiveness of various components downstream of the compressor. A model of oil liquefaction from vapor and aerosol states will be presented. The effect of liquefied oil combined with other contaminates in the pneumatic system and various design criteria for downstream equipment will be discussed.
Technical Paper

Benefits of Profiling Tapered Roller Bearings - Matching Driveline Component Performance to the Demands of Higher Horsepower Engines of Heavy Duty Trucks

1999-11-15
1999-01-3767
The heavy-duty trucking industry is continuing to move toward the use of higher horsepower engines. Engines exceeding 450 horsepower have become increasingly popular, with 500 - 600 horsepower engines expected to share a significant portion of the truck engine market in the next decade {Reference 1}. Sometimes these higher horsepower engines are used with existing gross combined vehicle weight, simply to increase the speed at which payloads are delivered. However, when higher engine horsepower is used to transport increased payloads, the result is higher loads and stresses on all driveline components between the engine and the wheels. All components downstream of the engine could be adversely affected.
Technical Paper

Steering Performance Evaluation - Heavy-Duty Highway Tractor Wander Test

1999-11-15
1999-01-3764
Heavy-duty highway tractors are the topic of various studies and tests to understand vehicle wander as a contributing factor to driver fatigue. Subtle variations in steering system characteristics can create measurable differences in performance, and operators may have different subjective opinions of the same system. This paper's purpose is to examine wander test setup and data analysis for tests conducted on an International® Model 9200 tractor-trailer at the Navistar Technology and Engineering Center in Fort Wayne, Indiana. Instrumented data and subjective ratings were collected using five power steering gears, evaluated by six drivers, operating over a specific test route.
Technical Paper

Electronic Compressor and Air Dryer Control

1999-11-15
1999-01-3771
The paper details opportunities for electronic control of the pneumatic charging system of an air braked vehicle. Electronic control of the charging and drying functions can result in increased fuel efficiency and improved air quality. Control functions can be used to identify and warn of in-service issues, provide prioritized system charging for faster drive-away, and signal required preventative maintenance. The first portion of the paper describes current industry practice, as well as common issues that can result from those practices. This is followed by presentation of areas of improvement, where specialized control features result in energy savings, air quality increases and maintenance/downtime savings. This portion will focus on adaptive control of components used today, and will briefly discuss opportunities for the next generation of charging system devices. The final section of the paper presents the control logic and vehicle interface allowing for system integration.
Technical Paper

Analytical Solution of Piston Ring Pack Lubrication for Truck Air Brake Compressor

1999-11-15
1999-01-3769
This paper presents an analytical solution of piston ring pack lubrication for two-cylinder truck air brake compressor. A system of nonlinear equations with seven variables was developed to describe lubrication phenomena of the piston ring pack for both fully flooded and starvation conditions. The full mass conservation boundary conditions defined by JFO ([14],[15]) theory were employed for complete description of the cavitation algorithm with enclosed and open cavitation patterns. Impact of the piston ring design parameters such as offset, crown height, and tension on the oil transport, lubrication conditions and friction losses of the compressor were discussed in details.
Technical Paper

Analytical Definition and Application of Straight Bevel Gear Tooth Form

1999-11-15
1999-01-3745
Although the methodology of straight bevel gear tooth form generation has been known for quite some time, few references are available in the literature. Presented in this paper are the general numerical procedures of spherical involute and octoid tooth form generations. We have proven that a tooth form generated from the latter approach, by simulating the rotation of a crown gear, matches exactly with the one from the former approach of unwraping a wire from a base circle. The advantage of using general numerical procedures rather than closed form equations is the flexibility of generating both standard and modified gear tooth profiles. In making the forging die, the gear tooth form must be developed with considerations of both the theoretical optimal geometry, and the dimensional compensation for heat treatment distortion.
Technical Paper

Investigation of Wheeled Tractors Ride Comfort Using Hydraulic Semi-Active Suspension System

1999-11-15
1999-01-3727
In this paper, an electronically controlled hydraulic semiactive system for the seat suspension of wheeled tractors is theoretically designed to improve the driver ride comfort. Using a three degrees of freedom mathematical model, the damping force controller is designed based on optimal control theory and Nelder / Mead Simplex minimization method to perform a limited state feedback information. The controller considers the damping constraint which adapts the actual damping between the prescribed limits. The model results are generated when excited by a statistically random road profile. The results are presented in time and frequency domains. The driver vertical acceleration for semi-active and conventional passive systems are compared at similar root mean square (r.m.s) value of suspension working space. The semiactive system achieved a significant improvement, 18 percent, over the passive system with no power requirement from the tractor engine.
Technical Paper

Simultaneous Visualisation of Spray and Flame Propagation in a Heavy-Duty Transparent-Engine with Common-Rail Injection System

2000-06-19
2000-01-1797
The transport of goods is mainly realised by the use of heavy-duty vehicles equipped with diesel engines as a drive assembly. Considering the high flexibility and reliability as well as the growing interest in saving environmental resources, a further optimisation of DI-diesel engines regarding fuel consumption and exhaust emissions is necessary. Current discussions on the application of different injection systems for passenger cars (distributor pump, common-rail, …) are also of great significance with regard to heavy-duty vehicles. Optical measurement techniques are a valuable tool to evaluate the quality and the potential of modern DI-diesel injection systems. In this work a conventional heavy-duty engine (MAN) was modified to carry out optical investigations inside the combustion bowl, concerning spray propagation and flame luminosity for different injection nozzles. With respect to the current discussions, it was equipped with a modern common-rail system.
Technical Paper

Plastic Tailgate: What Materialfor What Purpose

2000-03-06
2000-01-1072
Plastic tailgates are described : thermosets as well as thermoplastic, dismantable or non dismantable, paintedor unpainted, stiffened by metallic parts or not … Some help to choose the good material is given, depending on the application and the specifications of the tailgate. Finally, examples of the use of such materials are given showing parts which answer the specifications, and showing also innovations being possible thanks to the use of such materials.
Technical Paper

The Effect of Elliptical Nozzle Holes on Combustion and Emission Formation in a Heavy Duty Diesel Engine

2000-03-06
2000-01-1251
A serie of experiments were carried out to compare the combustion and emissions characteristics of a diesel engine using non-circular (elliptical) and circular shaped fuel injector nozzle holes. Elliptic nozzle holes have the potential to increase air entrainment into the spray, which could lead to decreased emissions from diesel combustion. Previous work [6,7] has shown some interesting results in a passenger car diesel engine and also in a single cylinder engine with optical access. The idea is based on results from investigations of gas jets, where the air entrainment for elliptical jets was increased substantially compared to circular jets. The present series of experiments were carried out to further investigate these effects. The non-circular holes, which were made with an aspect ratio of close to 2:1, have a similar flow rate as the conventional circular holes. Two different angles of the elliptical major axis to the injector centerline were used.
Technical Paper

Performance of High Oleic Soybean Oil Based Hydraulic Fluids in Long-Duration Pump Tests

2000-09-11
2000-01-2556
Tests were performed to evaluate the performance of high oleic soybean oil-based hydraulic fluids in long-duration pump tests. Formulations for a conventional hydraulic fluid and a food grade fluid were operated in a low volume hydraulic system for up to 1000 hours. Traditional measures of fluid performance including pump wear, total acid number and viscosity change indicate overall acceptable fluid performance. In addition, a methodology for studying the time-dependent change in pump cartridge surface roughness was investigated. Results indicate that changes in pump roughness correlate with changes in other traditional measures of fluid performance and this additional wear parameter could be useful in developing models to better understand the time-dependent behavior of the system and thus to guide efficient development of enhancements to the oil-additive package.
Technical Paper

Switching Type Control of Hydraulic Drives - a Promising Perspective for Advanced Actuation in Agricultural Machinery

2000-09-11
2000-01-2559
Further advances in agricultural machinery require - amongst others - means for fast and precise positioning. Hydraulic drives fit very well to the environmental conditions of this machinery and can provide the required performance. State of the art methods of fluid power control by servo or proportional valve technology are not adequate for cost and maintenance reasons. Switching techniques are an alternative. Various concepts of switching exist. Some of these also show good efficiency. To put these techniques to practice requires very fast switching valves which currently are not available. One promising concept to realize such valves is outlined.
Technical Paper

Steel Quality Requirements for Heavy Duty Off-Highway Gearing

2000-09-11
2000-01-2566
The bearing industry has long recognized that reducing the total number and size of large aluminum oxide inclusions proportionately increases contact fatigue life. Improved geometric accuracy and surface finish on heavy duty off-highway carburized gearing has increased the significance of oxide inclusions in nucleating contact and bending fatigue fractures. While modern steel making technology can regularly provide high quality steel with controlled cleanliness, the absence of an industry standard specification makes procurement difficult. Key quality and steel cleanliness requirements have been written into CNH's alloy gear steel specification. A detailed questionnaire has been developed and is utilized to help identify steel mills that have the modern equipment and processes needed to produce high quality gear steel.
Technical Paper

Comparison of Plain Bushing Technologies for Reduced Grease Consumption in Construction Equipment

2000-09-11
2000-01-2603
In construction and agricultural equipment, joints using plain bearing / shaft assemblies need to fulfill demanding requirements regarding reduced grease consumption and maintenance, load bearing capacity, resistance to shocks, overloads and abrasion. The behavior of an innovative bearing design, based on the combination of steel as core material, special surface topography and high technology surface treatments is studied. Surface topography, composition of the friction layer and base material turn out to have a considerable influence on the behavior of the joint. This new bearing design is compared with other common industrial bearing technologies and is found to be the best compromise in terms of resistance to adhesive and mechanical wear under high load oscillatory motion.
Technical Paper

Development of Heat Resistant Long Life Through Hardening Bearing Steel (STJ2)

2000-09-11
2000-01-2602
The development of a long life rolling element bearing for use under severe conditions is fundamental and important technology from an economic and environmental standpoint. Previously, NTJ2 was developed as a semi-heat resistant long life bearing steel, using silicon as an alloying element to enhance its heat resistance and life. It is thought, though, that the demand for a bearing material that can withstand higher temperatures and have a longer life than NTJ2 will be needed in the future. Thus, a new heat resistant, long life material called STJ2 was developed optimizing the alloying elements in the silicon-alloyed bearing steel. The new steel has good dimensional stability to 250°C, long life and is very resistant to surface damage.
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