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Technical Paper

“Seizure-Delay” Method for Determining the Seizure Protection of EP Lubricants

1939-01-01
390146
IT does not yet seem to be recognized fully that it is the local temperature at the surface of contact and not the local specific pressure that chiefly determines the occurrence of seizure under extreme-pressure-lubrication conditions. This local temperature is the result of the temperature level of the parts lubricated, considered as a whole (“bulk” temperature) and of a superimposed instantaneous temperature rise (temperature “flash”) which is localized in the surface of contact. It appears typical for extreme-pressure-lubrication conditions, as met in gear practice, that the temperature flash is much higher than the bulk temperature. With existing conventional test methods for the determination of the protection against seizure afforded by EP lubricants, a considerable rise of the bulk temperature mostly occurs; as it cannot be controlled sufficiently; thus, leaving an unknown margin for the temperature flash, it renders impossible a reliable determination.
Technical Paper

“Rubber Coupling” at a 4×4 Transmition System

2003-11-18
2003-01-3684
There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.
Technical Paper

“Projection-by-Projection” Approach: A Spectral Method for Multiaxial Random Fatigue

2014-04-01
2014-01-0924
This paper presents a fatigue criterion based on stress invariants for the frequency-based analysis of multiaxial random stresses. The criterion, named “Projection-by-Projection” (PbP) spectral method, is a frequency-based reformulation of its time-domain definition. In the time domain PbP method, a random stress path is first projected along the axes of a principal reference frame in the deviatoric space, thus defining a set of uniaxial random stress projections. In the frequency-domain approach, the damage of stress projections is estimated from the stress PSD matrix. Fatigue damage of the multiaxial stress is next calculated by summing up the fatigue damage of every stress projection. The criterion is calibrated on fatigue strength properties for axial and torsion loading. The calculated damage is shown to also depend on the relative ratio of hydrostatic to deviatoric stress components.
Technical Paper

“Insert and Fly” Using PCMCIA PC Cards in the Avionics Market

1994-11-01
942553
When looking into using PCMCIA PC Cards in the avionics market, three areas must be researched. The first is what are the applications and benefits of using the PC Cards while in flight, followed by the applications and benefits on the ground, and thirdly on how to make a PC Card that would stand up to the rugged avionics environment. PCMCIA PC Cards can be used in all aspects of flight. Three possible applications on the ground are; paperless documentation, modifications, flightline changes. Once airborne, PC Cards can be removed and a different functionality card can be inserted. One PC card socket can be used for many different functions during one flight. Some of the possible applications for PC Cards inflight are; flight plan changes, backup Line Replaceable Units (LRUs), and solid state data collection.
Technical Paper

“Evaluation of the Drift of vehicle Inspection/Maintenance Emission Analyzers in use- A California Case Study”

1989-05-01
891119
Quality assurance (QA) in motor vehicle emissions inspection/maintenance (I/M) programs is a continuing concern, especially in decentralized programs with hundreds or even thousands of licensed stations. The emissions analyzers used in such stations are an important focus of governmental QA efforts because of the central role of analyzers in determining which vehicles need to be repaired. Therefore, the In-use performance of I/M emission analyzers has a large impact on the quality of 1/M programs as a whole. This paper reports on the results of an investigation in California designed to determine in-use performance of emission analyzers in the field. The investigation was designed to evaluate both drift rates and the ability of analyzer systems with automatic gas calibration capability to correct analyzer responses outside of accepted tolerances.
Technical Paper

Zero G Liquid Propellant Orientation by Passive Control

1964-01-01
640239
This paper discusses the advantages and problems associated with the use of “passive” liquid containment systems that utilize liquid intermolecular forces for propellant orientation in reduced or zero gravity environments. Liquid orientation is required to provide reliable engine restart and tank venting operations of space vehicle propulsion systems. Various liquid containment system concepts, and associated design criteria, are presented and general problem areas of interface stability, liquid slosh, and effects of thermal energy are described. Descriptions of present and planned test facilities designed to provide reduced gravity environments and extended time durations are included. It is concluded that additional design criteria in the problem areas discussed must be obtained before “passive” liquid containment systems can replace systems now used in reduced or zero gravity environments.
Technical Paper

ZINCROMETAL: Its Manufacture, Testing,and Use

1977-02-01
770362
ZINCROMETAL usage in the automotive sector has increased rapidly since 1972. As one might expect, this has led to considerable interest in the details of producing this product. In order to fulfill this expressed need, a description of the manufacture of ZINCROMETAL is presented here. Since the process is inextricably involved with a variety of quality control and quality assurance testing procedures, they are incorporated into this paper also. Finally, a long but incomplete listing of parts where ZINCROMETAL has been applied in auto bodies is reviewed.
Technical Paper

Yield Monitors, Combines, and Their Interactions

1999-09-14
1999-01-2846
Instantaneous combine grain yield monitors need to provide reliable yield measurements since yield as a function of location is key information needed to manage fields by management zones. A scale and a yield monitor measured the same stream of grain and provided similar results when compared to each other. Data from either device may be misinterpreted if care in calibration and operation is not taken. Careful operators who pay attention to calibration, maintenance, and manufacturer's instructions will be required.
Technical Paper

YOUR LIVING ROOM ON WHEELS

1956-01-01
560148
From mohair plush to woolens, to patterns and now synthetics - that's the growth of automotive fabrics. The 1956 models have gig-finished woolen system broadcloths, tweeds made with spun yarns, Jacquards with spun and filaments, dobby patterns on both woolen and worsted systems and a wide use of boucle or novelty yarns. Fabric designing has become a highly specialized art, attuned always to the stylists' demands. Abrasion, dye stability and light fastness, durability, shrinkage and stretch, cost, spotting and water repellency are all important factors. Where physical requirements are about the same from all automobile manufacturers, they greatly vary in interpretations of results. Where do we go from here? There are synthetics yet untried; some may be blended with natural fibers. By taking the textile supplier more into their confidence, automobile builders would help chart the course ahead.
Technical Paper

Xerox's Distributed Real Time Control System

1987-02-01
870517
XEROX has developed and implemented a network architecture for a real time control system which has expansion flexibility, high reliability, noise immunity, and low cost. This two level multiplex system with a single wire system bus at one level for distributed processors connected to local serial buses at the second level for remote functions and loads is described. The XEROX Microelectronics Center has developed a set of custom VLSI chips to implement the multiplexing architecture. Control software was developed using both assemblers and high level language tools. The software and chip set have been designed, built and integrated into XEROX'S latest generation of products.
Technical Paper

X-38 Nose Skirt Panels - Results of Qualification Testing

2001-07-09
2001-01-2343
The X-38 vehicle will be used to demonstrate the future technology on durable TPS for the CRV. Astrium has produced two large CMC Nose Skirt side panels for the current X-38 configuration. The design of the 3 dimensional curved and large side panels comprises a light-weight, stringer stiffened concept which compensates the thermal expansion by a system of flexible metallic stand-offs. An optimum in flexibility and stiffness to fulfil all requirements had to be found: strong and stiff enough to carry the thermo-mechanical loads, but flexible enough to realise a fastening concept which does not fail due to thermal expansion. The fastening concept has been tested on development test level. Some thermal and mechanical tests on sub-structure level confirmed the design and analysis work of the complete TPS concept.
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