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Standard

在 9100 质量管理体系内 应用 AQAP 2110 的指南

2024-02-16
IA9137_ZHCN
编制和发布本文件旨在供应商遵守 9100 规定的情况下,就 AQAP-2110 的应用提供相关信息和指南。本文件的发布号为 AQAP-2110-SRD.2 和 IA9137。本文件由 NATO 和行业代表联合编制,供 NATO 和行业内使用,旨在促进 AQAP-2110 和 9100 的使用及对其之间关系的理解。当采购国使用对外军售 (FMS) 作为其采购方式时,可能需要 AQAP。 本文件旨在促进采购方及其 9100 供应商对 AQAP-2110 要求解释的通用性。 本文件内容不具有法律或合同地位,亦不会取代、增加或取消 AQAP-2110 或 9100 的任何要求。 由于可能存在多种条件(取决于工作或过程类型、所用设备和所涉人员的技能等因素),不应将本指南视为包含所有事宜,亦不应将本指南视为强加满足合同要求的具体手段或方法。相关方应意识到,可使用其他手段或方法来满足这些要求。 本指南使用者应谨记,当合同引用了 AQAP 2110,其要求对于供应商和次级供应商具有强制性。
Journal Article

“Sticky” Lining – the Phenomena, Mechanism and Prevention

2008-04-14
2008-01-0819
An unique bonding mechanism was studied after several instances, where the linings stuck to the brake drums on transit buses, were reported. Evidences suggested that the linings were “glued” to the brake drums surface after wear debris (dust) was turned into “adhesive paste” through complicated thermal and chemical changes. Factors such as the friction materials, environment and service conditions, which could activate and deactivate the lining bonding, were observed and discussed. The prevention measures are proposed.
Technical Paper

“Smart sensing” of Oil Degradation and Oil Level Measurements in Gasoline Engines

2000-03-06
2000-01-1366
Proper lubrication of moving parts is a critical factor in internal combustion engine performance and longevity. Determination of ideal lubricant change intervals is a prerequisite to ensuring maximum engine efficiency and useful life. When oil change intervals are pushed too far, increased engine wear and even engine damage can result. On the other hand, premature oil changes are inconvenient, add to vehicle maintenance cost, and result in wasted natural resources. In order to determine the appropriate oil change interval, we have developed an oil condition sensor that measures the electrical properties of engine oil, and correlates these electrical properties to the physical and chemical properties of oil. This paper provides a brief background discussion of the oil degradation process, followed by a description of the sensor operational principles and the correlation of the sensor output with physical and chemical engine oil properties.
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

“RoHS” Compliant Chrome - Free Conversion Coating for Aerospace Manufacturing

2006-09-12
2006-01-3130
This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.
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

“In-Car” Fatigue Data Acquisition

1969-02-01
690172
“In-car” measurement of vehicle loads and stresses is a basic step in solving fatigue design problems associated with passenger cars. The application includes measuring systems and techniques for evaluating fatigue design problems related to energy-absorbing steering columns and automotive gas turbines.
Technical Paper

“Impact of Design Principles on End-of-Life and Recycling”

2024-01-16
2024-26-0163
Automotive industry is a major contributor to global carbon dioxide (CO2) emissions and waste generation. Not only do vehicles produce emissions during usage, but they also generate emissions during production phase and end of life disposal. There is an urgent need to address sustainability and circularity issues in this sector. This paper explores how circularity and CO2 reduction principles can be applied to design and production of automotive parts, with the aim of reducing the environmental impact of these components throughout their life cycle. Also, this paper highlights the impact of design principles on End-of-Life Management of vehicles. As Design decisions of Component impacts up to 80% of emissions [1], it is important to focus on this phase for major contribution in reduction of emissions.
Technical Paper

“Fatigue Behavior of Sheet Steels for Automotive Industry”

1992-11-01
921439
Carbon and rephosphorized pre-strained sheet steels for cold drawing forming operations were studied and the tensile, high cycle fatigue and fatigue crack propagation properties were determined. The fatigue limit was found to be higher for 20% than for 1% pre-strained condition. Threshold stress intensity factors (▵Ků) of 5.29 MPa. m1/2 for rephosphorized steel and 7.07 MPa. m1/2 for carbon steel. Critical crack lenghts were calculated by ▵Ků and fatigue limit data using the Lukas-Klesnil short-crack criterion. Through fractographic analysis it was possible to determine the general behavior of tested materials near threshold.
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

“Derivation of Conduction Heat Transfer in Thin Shell Toroids”

2000-07-10
2000-01-2487
This paper presents the derivation of the equations for circumferential, longitudinal and radial heat transfer conductance for a thin shell toroid or a segment of the toroid. A thin shell toroid is one in which the radius to thickness ratio is greater than 10. The equations for the surface area of a toroid or of a toroidal segment will also be derived along with the equation to determine the location of the centroid. The surface area is needed to determine the radial conductance in the toroid or toroidal segment and the centroid is needed to determine the heat transfer center of the toroid or toroidal segment for circumferential and longitudinal conductance. These equations can be used to obtain more accurate results for conductive heat transfer in toroid which is a curved spacecraft components. A comparison will be made (1) using the equations derived in this paper which takes into account the curvature of the toroid (true geometry) and (2) using flat plates to simulate the toroid.
Technical Paper

“DELRIN” ACETAL RESIN —a new engineering material

1959-01-01
590033
“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.
Technical Paper

“Bump Test” of Wet Friction Materials: Modeling and Experiments

2001-03-05
2001-01-1154
In one of the fatigue tests for wet friction materials, “bump test”, an inertia-type rig equipped with a multi-disk assembly is used. One of the steel disks in the assembly has radial bumps for the purpose of creating high local contact pressure and high temperature. Due to the severe contact conditions, a comparative testing for different friction materials can be conducted within a relatively small number of cycles. In the paper, a design of a “bump” assembly used for automotive wet friction materials is described. Based on both experimental tests and advanced contact modeling, non-uniform contact pressure generated by the bumps and resulting temperature are estimated. The computational model is used then to study the influence of the modulus of elasticity of the friction material and reaction plate thickness on the contact conditions. The bump fatigue tests lead ultimately to material failure.
Technical Paper

‘Skins’ by Design: Humans to Habitats

2003-07-07
2003-01-2655
Whether we live on land, underwater, or out there in space, what makes it possible is our ‘skin’. The one we were born with, the one we wear, the one we live in, and the one we travel in. The skin is a response to where we live: it protects as our first line of defense against a hostile environment; it regulates as part of our life-support system; and, it communicates as our interface to everything within and without. In the context of space architecture – we, our space suits, vehicles and habitats are all equipped with highly specialized ‘skins’ that pad us, protect us and become an integral part of the design expression. This paper approaches the subject from a holistic perspective considering ‘skins’ and their manifestation as structure, as vessel, as texture, and as membrane. The paper then goes on to showcase innovative use of materials in practice through two case studies: the ‘spacesuit’ and ‘inflatable habitats’.
Technical Paper

‘Bigelow Aerospace® Life Support Laboratory - Planning and Status’

2004-07-19
2004-01-2474
This Life Support Laboratory consists of a simulator of the spacecraft called Nautilus, which houses Air Revitalization Subsystem, Atmospheric Control and Supply, and Fire Detection and Suppression in the Equipment Area. There are supporting facilities including a Human Metabolic Simulator, simulated Low and Moderate Temperature Coolant Loop, chemical analysis bench, purified water supply, vacuum and gas supplies. These facilities are scheduled to be completed and start to operate for demonstration purposes by March 2005. There are an ARES Ground Model (AGM) and a Trace Contaminant Control Assembly in the ARS. The latter will be integrated with the AGM and a Condensing Heat Exchanger. The unit of AGM is being engineered, built, and will be delivered in early 2005 by EADS Space Division. These assemblies will be operated for sensitivity analysis, integration and optimization studies. The main goal is the achievement for optimal recovery of oxygen.
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