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Viewing 1 to 30 of 13969
2016-06-27 ...
  • June 27-28, 2016 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
Training / Education Classroom Seminars
The purpose of this course is to provide an overview of the factors in the cylinder kit assembly of natural gas, gasoline, and diesel engines that affect oil consumption, ring and cylinder bore wear, and blow-by. This course includes background and the evolution of designs and materials currently employed in modern engines as well as providing an overview of computer models, designs, and material systems that can be utilized to optimize the performance of new engines. An overview of the trends in materials and designs employed in U.S., European and Japanese engines will be presented.
2015-09-29
Technical Paper
2015-01-2871
Mounika Katragadda, Kalyan Deepak Kolla, Venkata Suresh Yaparala
Fatigue that is induced due to vibration is known as vibration induced fatigue. There are two approaches to evaluate this, viz., time & frequency domain. A straight forward and widely used method is rainflow counting technique in time domain. This counting algorithm is readily available and apart from the time history, it needs only one variable input (number of stress ranges). In case of longer time histories, time domain approach may consume lot of time and resource, which shifts our interest towards frequency domain methods. In frequency domain, Dirlik's method is proven to be robust and gives closer results to time domain. Since Dirlik's approach is probabilistic, there are different variables (such as stress ranges, scaling factor for RMS value to predict maximum stress etc.) to be considered for cumulative fatigue damage evaluation.
2015-09-29
Technical Paper
2015-01-2758
Zhigang Wei, Robert Rebandt, Michael Start, Litang Gao, Jason Hamilton, Limin Luo
Bench testing is commonly used to construct fatigue design curves, which are used for the durability and reliability assessment of engineering components subjected to cyclic loading. Several criteria, such as R90C90 and R99C50, are widely used in automotive industry to construct fatigue design curves for a typical testing sample allocation, i.e. two stress/load levels and 6 data points at each stress/load levels. In order to reduce the test sample size and associated testing cost, recently, a Bayesian statistics based design curve construction method has been successfully developed. The Bayesian method is based on a large amount of reliable historical fatigue test data, the associated probabilistic distributions of the mean and standard deviation of the failure cycles, and an advanced acceptance-rejection resampling algorithm.
2015-09-29
Technical Paper
2015-01-2759
Zhigang Wei, Limin Luo, Shengbin Lin, Litang Gao, Fulun Yang
The linear damage accumulation models based on Miner’s rule are widely used for fatigue damage assessment of vehicle components and systems. However, the uncertainty nature of the damage accumulation process is not considered in most of the applications, in others words, the methods themselves are deterministic in nature. In engineering design and validation, understanding the lower bound, upper bound of damage status in addition to mean behavior will be beneficial in risk and safety assessment, and these goals cannot be achieved without the probabilistic concepts and tools. This study presents a general damage assessment approach, which consists of two key parts: (1) an empirical probabilistic distribution obtained by fitting the fatigue failure data at various stress range levels; and (2) an inverse technique, which transforms the failure distribution to the damage distribution at any applied cycle.
2015-09-29
Technical Paper
2015-01-2728
Paul C. Cain
OEM benefit: Vehicle manufacturers desire continuous feedback in monitoring key safety sub-assemblies. In this application, engineers are calculating the remaining brake pad life by monitoring the current thickness of the brake pad friction material. This information is used in scheduling preventative maintenance activities and avoiding safety incidents. Unplanned machine down time and field repair costs in earthmoving equipment is cost prohibitive. This technology allows OEM's to have high confidence, continuous feedback on this critical vehicle safety feature avoiding expensive, unplanned repairs and improving field "up time" performance. Application challenge: Developing a reliable linear position sensor that is suitable for continuous monitoring of brake pad material thickness in a high pressure, high temperature, high vibration and contaminated environments typical of large construction (earthmoving) vehicles.
2015-09-27
Technical Paper
2015-01-2684
Seongjoo Lee, ShinWook Kim, ShinWan Kim, Seong Rhee
A correlation between brake squeal and disc wear was reported previously. This investigation was undertaken to confirm the correlation and to characterize the disc wear particles transferred to the sliding surface of the NAO pad. It is found that the iron distribution on the pad is very non-uniform; at some locations, the iron concentration reaches the level of Low Steel Lomets (15-20wt%); and squealing brakes exhibit increased amounts of transferred disc wear particles on the pad surface. These transferred particles are found as small and flattened thin metallic sheets, which are different from relatively large “metal pick-up” pieces.
2015-09-27
Technical Paper
2015-01-2675
Erik Tobin, David Bortz, Tod Policandriotes
This paper describes test results from a new, copper-free para-aramid needlefelt composite friction material enhanced with nanoparticles. Kevlar felt-reinforced polyimide, enhanced with nanoparticles, exhibit a higher coefficient of friction than similar friction materials without nanoparticles but retain the low wear rate exhibited by those materials during full scale dynamometer testing, using the J2430 test. The threshold nanoparticle content to produce appreciable friction coefficient gains was determined. At the content levels investigated, the rotor wear was virtually undetectable while wear rate was comparable with those materials without nanoparticles. Agglomeration and distribution of nanoparticles was investigated as it pertains to friction performance and wear. New environmental regulations limiting copper content in friction materials will restrict the use of popular components found in conventional friction.
2015-09-27
Technical Paper
2015-01-2662
Daniela Plachá, Pavlina Peikertova, Jana Kukutschova, Poh Wah Lee PhD, Kristina Čabanová, Jiří Karas, Jana Kuchařová PhD, Peter Filip
The brake wear contribution to the environmental pollution has been extensively discussed, with major focus on asbestos and heavy metals released to the environment. Only limited attention was paid to released organic compounds generated during friction processes, although the organic and carbonaceous components are not the minor part in brake lining formulations. Friction processes in brakes are associated with relatively high temperatures and high pressures on the friction surfaces which relates to the thermal decomposition of the organic components in friction materials and to brake lining thermal fade. Thus, this study focuses on the identification of organic compounds released from a model low metallic brake material.
2015-09-27
Technical Paper
2015-01-2679
David B. Antanaitis
The proposed paper will describe how brake pad sizing (area and volume) affects fade behavior and useable life on the race track, and propose a methodology for determining the optimal brake pad size for high performance vehicles.
2015-09-27
Technical Paper
2015-01-2692
Giulia Garello, Niccolò Patron, Pietro Buonfico, Luca Martinotto
Nature of braking friction is extremely complex and a deeper understanding of the physical mechanisms that govern the energy dissipation at the interface of friction pair is an important tool to create an even deeper knowledge of tribological behavior of friction material. Friction brakes need to transform kinetic energy into heat: a complete knowledge of thermal effects during this process in every brake component is an essential part of brake design. As referred to brake pads, the analysis of dyno testing data highlighted experimental evidences related to thermo-mechanical effects, such as the different wear resistance capabilities of material classes (NAO and Low Steel). Tribological characteristics are not constant under all testing conditions and they strongly depend on temperature being the direct consequence of kinetic energy dissipation. The aim of this work is to explain the relation between wear and energy for different type of friction materials.
2015-09-17 ...
  • September 17-18, 2015 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
  • April 11-12, 2016 (8:30 a.m. - 4:30 p.m.) - Detroit, Michigan
Training / Education Classroom Seminars
The transportation industry, including motor vehicles, aircraft, rail, marine, commercial, off-road and defense vehicles, as well as infrastructures, energy sectors, raw materials, manufacturing, health and food industries all experience significant issues with corrosion which results in billions of dollars of loss each year. Corrosion education and prevention is essential to improve and increase the service life of parts and components which may have a significant impact on the economy of various industries and nations.
2015-09-15
Technical Paper
2015-01-2596
Uli Burger, Ludovic Rochat
Lightweight structures are one key issue for all future mobility concepts. Carbon fibre reinforced plastics (CFRP) play an important role in these disciplines due to their outstanding mechanical performance regarding to their weight. Therefore, CRFP structures have been widely used since decades in aerospace industry resulting in improvements in payload, fuel consumption and range. The Airbus A350, Boeing B787 in civil airplane industry as well as military products like the NH90 transport helicopter are examples of this development towards “all composite”-aircrafts with nearly all structural parts made out of composite materials. A main difference of CFRP-structures towards metallic ones is the behavior regarding damage tolerance and fatigue. For helicopter composite structures this issue is newly defined in §573 of the relevant certification specifications (CS for EU, FAR for US) valid since December 2012.
2015-09-15
Technical Paper
2015-01-2613
Douglas Leicht, Kirk Olsen
15-5PH is a precipitation-hardening, martensitic stainless steel used for primary structural elements such as engine mounts where corrosion resistance, high strength, good fatigue and fracture toughness is required. The material composition is defined in AMS5659M and can be either type 1-vacuum arc remelt (VAR) or type 2-electro slag remelt (ESR) heat treated per SAE AMS-H-6875B to condition H1025 to an ultimate tensile strength of 155-175 ksi. Typical material handbooks have limited fatigue data which are only type 1 material. Therefore, the fatigue properties of 15-5 PH H1025 stainless steel for both type 1 and type 2 were determined. The objective of the fatigue testing was to generate a family of S-N curves (maximum stress versus number of cycles to failure) for a series of stress ratios across the entire range of cycles to failure.
2015-07-28
Standard
AMS2231K
This specification covers established inch/pound manufacturing tolerances applicable to carbon steel bars ordered to inch/pound dimensions. These tolerances apply to all conditions, unless otherwise noted. The term “excl” applies only to the higher figure of the specified range.
2015-07-17
WIP Standard
AMS2430U
This specification covers the requirements for automatic shot peening of surfaces of parts by impingement of media, including metallic, glass, or ceramic shot.
2015-07-07
WIP Standard
D15AB
This specification covers an aluminum alloy in the form of sheet and plate clad on both sides.
2015-07-06
Standard
AMS4984F
This specification covers a titanium alloy in the form of forgings 3.000 inches (76.20 mm) and under in nominal cross-sectional thickness and of stock for forging of any size.
2015-07-02
WIP Standard
AS5502D
This document establishes standard requirements for aerospace sealants and adhesion promoters, which may be incorporated as part of Aerospace Material Specifications (AMS) for such products. This document provides for commonality of methods and procedures for responsibility for inspection, source inspection, classification of tests, establishment of/and qualification to qualified products lists, approval, reports, resampling and retesting, packaging, and marking.
2015-06-23
WIP Standard
AMS4598B
This specification covers a copper-nickel-tin alloy in the form of mechanical tube.
2015-06-15
Technical Paper
2015-01-2213
John Van Baren
Abstract Random vibration control systems produce a PSD plot by averaging FFTs. Modern controllers can set the Degrees of Freedom (DOF), which is a measure of the amount of averaging to use to estimate the PSD. The PSD is a way to present a random signal-which by nature “bounces” about the mean, at times making high excursions from the mean-in a format that makes it easy to determine the validity of a test. This process takes time as many frames of data are collected in order to generate the PSD estimate, and a test can appear to be out of tolerance until the controller has enough data to estimate the PSD with a sufficient level of confidence. Something is awry with a PSD estimate that achieves total in-tolerance immediately after starting or during level changes, and this can create dangerous over or under test conditions within specific frequency bands and should be avoided.
2015-06-15
Journal Article
2015-01-2227
Scott Allen Noll, Benjamin Joodi, Jason Dreyer, Rajendra Singh
Abstract Elastomeric joints such as mounts and suspension bushings undergo broadband excitation and are often characterized through a cross-point dynamic stiffness measurement; yet, at frequencies above 100 Hz for many elastomeric components, the cross- and driving-point dynamic stiffness results significantly deviate. An illustrative example is developed where two different sized mounts, constructed of the same material and are shaped to achieve the same static stiffness behavior, exhibit drastically different dynamic behavior. Physical insight is provided through the development of a reduced order single-degree-of-freedom model where an internal resonance is explained. Next, a method to extract the parameters for the reduced order model from a detailed finite element bushing model is provided.
2015-06-12
WIP Standard
AMS4990C
This specification covers a titanium alloy in the form of sheet, strip, and plate. This material is typically used for parts requiring high strength-to-weight ratio and stability up to 550 °F (288 °C), but usage is not limited to such applications.
2015-05-13
Technical Paper
2015-36-0009
Evandro Benincá, Mauricio da Silva, Ruy Alberto Bueno Jr., Vagner do Nascimento
Abstract One effect which is present in drum and disc brakes is the temperature. This effect significantly changes the vehicle and semi-trailer combinations performance, mainly in drum brakes that is more susceptible to this factor. High temperatures mean loss of efficiency, higher lining wear, brakes and rolling systems components life reduction and could be caused by many factors, which can be mentioned, overload, error in design and choice of brake system, speeding, over adjustment (dragging) and environment heat exchange. The challenge is to comprehend the relation between different brake configuration and how these configurations affects the temperatures generation on brake system, allowing that this factors can be evaluated during the project design. This paper aims to show a case study for a new brake family to be used in city bus application where the fleets are looking for better, safety, performance and low lining wear reduce the to increase the maintenance time.
2015-05-07
Standard
J2975_201505
This procedure describes a method for generating, preparing and analyzing samples of new and unused brake friction materials for their chemical constituents.
Viewing 1 to 30 of 13969

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