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欧洲与北美制造的烧结青铜含油轴承性能的比较

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粉末冶金技术 2006年第4期24卷 304-309页

作者： Haward I.Sanderrow Leander F.Pease 韩凤麟 President Management & Engineering TechnologiesMET Group Inc. President Powder-Tech AssociatateInc.

多孔性青铜含油轴承是全世界都在生产的,最早与最无处不用的现代粉末冶金产品。然而,各地区产品之间仍存在着明显差异。近期发布的粉末冶金材料的全球标准ISO5755,其中有2个描述轴承材料性能的数据表。其中列举的几项关键性轴承特性和M... 详细信息

多孔性青铜含油轴承是全世界都在生产的,最早与最无处不用的现代粉末冶金产品。然而,各地区产品之间仍存在着明显差异。近期发布的粉末冶金材料的全球标准ISO5755,其中有2个描述轴承材料性能的数据表。其中列举的几项关键性轴承特性和MPIF标准35或相应的ASTM标准中列出的轴承性能有所不同。因此,MPIF标准委员会进行一项小型试验,对标准90%(质量分数)Cu-10%(质量分数)Sn轴承的关键特性进行了对比。这项研究的样品零件来自欧洲与北美的大批量生产厂家。数据证实孔隙度与径向压溃强度不同,这种差异是原料粉与制造工艺的微妙差异所致。最终用户应该了解这些差异,和确认ISO5755中列举的特性能满足他们对轴承的要求。

关键词：粉末冶金轴承性能青铜含油轴承

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全球烧结金属含油轴承评定

粉末冶金技术 2008年第1期26卷 65-70页

作者： Howard Ⅰ.Sanderow Leander F.Pease 韩凤麟 President Management & Engineering TechnologiesMET Group Inc.161 Copperfield DriveDaytonOhio 45415-1264USA President Powder-Tech AssociatesInc.31 Flagship DriveNorth AndoverMassachusetts01845-6194USA

烧结金属含油轴承是当今全世界最早生产和使用最广的粉末冶金产品。以前对一种组成为中等石墨-青铜的轴承研究发现,北美制造的轴承和欧洲生产的同样产品之间有显著差异。为此,对北美、欧洲及日本提供的轴承,进行了比较详细的研究。每一... 详细信息

烧结金属含油轴承是当今全世界最早生产和使用最广的粉末冶金产品。以前对一种组成为中等石墨-青铜的轴承研究发现,北美制造的轴承和欧洲生产的同样产品之间有显著差异。为此,对北美、欧洲及日本提供的轴承,进行了比较详细的研究。每一地区至少提供二个生产厂商和二种不同合金的轴承试件。合金范围包括青铜、铁-铜及铁-石墨。测试结果证实了以前的发现,欧洲制造的青铜轴承和北美与日本生产的轴承不同,现在认为这是由于铜基粉末不同所致。还发现北美和日本制造的铁-石墨轴承的压溃强度不同。提出了这些研究的结果,包括证实力学性能不同的显微照片。另外,还评价了和国际标准ISO 5755有关的结论。

关键词：粉末冶金含油轴承烧结金属全球评定

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制造烧结金属含油轴承的高性能青铜粉

粉末冶金技术 2007年第5期25卷 387-392页

作者： Nic Veloff Anil Nadkarni Thomas Murphy 韩凤麟（译） SCM Metal Products Inc. 2601 week Dr. Research Triangle Park NC 27709 不详

自润滑青铜轴承的性能决定于许多因素的综合作用,诸如精整后的密度、径向压溃强度(RCS)、含油量、表面粗糙度、施加的载荷、轴的速度及孔隙结构。压坯与烧结体的密度以及烧结时的尺寸变化(DC),在轴承制造中都很重要。这篇文章阐述了生... 详细信息

自润滑青铜轴承的性能决定于许多因素的综合作用,诸如精整后的密度、径向压溃强度(RCS)、含油量、表面粗糙度、施加的载荷、轴的速度及孔隙结构。压坯与烧结体的密度以及烧结时的尺寸变化(DC),在轴承制造中都很重要。这篇文章阐述了生产高使用性能烧结轴承用的一系列新的青铜粉末。对使用性能的测定表明,与用标准的预混合青铜粉末制造的轴承相比,这些轴承摩擦系数较小,温升较低且稳定,而且径向压溃强度较高。性能优异是因为连通孔隙结构较细小,从而通过极好的毛细作用可吸入大量油。在理论上,较高的RCS可使轴承具有较高的承受载荷的能力。

关键词：粉末冶金自润滑轴承含油轴承青铜粉 S2G青铜粉

A Wavelet Spectrum Technique for Machinery Fault Diagnosis

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Journal of Signal and Information Processing 2011年第4期2卷 322-329页

作者： Derek Kanneg Wilson Wang eMech Systems inc. Department of Mechanical Engineering Lakehead University

Rotary machines are widely used in various applications. A reliable machinery fault detection technique is critically needed in industries to prevent the machinery system’s performance degradation, malfunction, or even catastrophic failures. The challenge for reliable fault diagnosis is related to the analysis of non-stationary features. In this paper, a wavelet spectrum (WS) technique is proposed to tackle the challenge of feature extraction from these non-stationary signatures;this work will focus on fault detection in rolling element bearings. The vibration signatures are first analyzed by a wavelet transform to demodulate representative features;the periodic features are then enhanced by cross-correlating the resulting wavelet coefficient functions over several contributive neighboring wavelet bands. The effectiveness of the proposed technique is examined by experimental tests corresponding to different bearing conditions. Test results show that the developed WS technique is an effective signal processing approach for non-stationary feature extraction and analysis, and it can be applied effectively for bearing fault detection.

关键词： Machinery Condition Monitoring Rotary Machines Bearing Fault Detection Non-Stationary Signal Wavelet Transform Resonance Feature

The Evolution of Reliability and Efficiency of Aerospace Bearing Systems

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Engineering（科研） 2017年第11期9卷 962-991页

作者： Peter Gloeckner Charles Rodway FAG Aerospace GmbH & Co. KG Schweinfurt Germany FAG Aerospace inc. Stratford Canada

The worldwide air traffic underwent a rapid development in recent decades.?Between the early 70s and the late 90s of the last century civil air traffic?doubled every 15 years. The civil aviation market will continue to grow with 4% - 5%?each year within the next 20 years. This enormous growth represents major?challenges for airframers, engine makers, suppliers, airlines, air traffic management?and ground infrastructure. In addition, the public debate on the worldwide?civil air traffic is dominated by environmental and climate issues, even though only 2% of the man-made carbon dioxide (CO2) emissions are due to air transportation. Therefore the aerospace industry will have to focus on a low-emission and quite air traffic, and on the conservation of natural resources and our environment. The end-use consumer and environmental policy requirements?for aircrafts of the next generation translate into components with improved efficiency and reliability. Rolling bearings are one of these components which?significantly determine the reliability and mechanical efficiency of aerospace applications such as aircraft and rotorcraft engines and transmission systems.?They have to withstand very demanding operating conditions. Especially main shaft?bearings in modern aircraft engines experience high rotational speeds andtemperatures. Furthermore aerospace bearings have to meet the highest reliability?standards and require low-weight design solutions. These operating conditions?and requirements present a continuous challenge for improvements in all?fields of bearing technology. This article presents solutions in aspects of materials, design, analysis, and surface technologies in order to meet the environmental, reliability, and economical requirements of advanced aerospace bearing systems. State of the art bearing analysis and advanced bearing design solutions?contributing to lower friction power losses and inc.eased systems efficiency?are discussed. Weight, functional, and maintenan

关键词： Rolling Element bearings Aviation Environment Friction Efficiency Aircraft Engines Helicopter

Strength of plastic with various helical wheels meshed types of worms

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材料与冶金学报 2015年第3期14卷 232-235,238页

作者： Makoto Nomura Takao Koide Akio Ueda Yusuke Ishida Atsutaka Tamura Tottori University 4 - 101 Minami Koyama - cho Tottori 680 - 8552 Japan Amtec inc. BayTower 2510 1-2-1 Minato-ku Benten Osaka 552-0007 Japan

This study investigates the strength of plastic helical wheels meshed with enveloping and cylindrical worms whose tooth profiles mesh in line contact with helical wheels. Running fatigue tests of plastic helical wheels together with a conventional cylindrical involute worm, a line contact enveloping worm, and a line contact cylindrical worm were conducted. The tooth bearings, tooth temperatures, and fatigue lives of plastic helical wheels meshed with the different worms were examined at various center distances. Main results obtained are as follows ： The lives of both line and point contact wheels depended upon backlash, but the lives of line contact wheels are more sensitive to backlash than those of point contact wheels. At the backlash that maximizes the wheel life, the line contact wheels last longer than point contact wheels at smaller applied torques, but the influence of worm type on wheel life reduced at higher applied torque.

关键词：塑钢涡轮复合材料

Seismic behavior assessment for design of integral abutment bridges in Illinois

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 573-589页

作者： Derek L.Kozak Larry A.Fahnestock James M.LaFave KPFF Consulting Engineers inc 1601 Fifth AvenueSuite 1600SeattleWA 98101USA Dept.of Civil and Environmental Engineering Univ.of Illinois Urbana-ChampaignUrbanaIL 61801USA

Integral abutment bridges(IABs)minimize deterioration and degradation of the abutment seats and bearings due to water,dirt,and deicing chemicals by eliminating bearings and expansion *** the continuity between superstructure and abutments in an IAB is beneficial for reducing maintenance costs,it leads to more complex behavior under strength and service loading(temperature and traffic)and extreme loading(earthquake).The coupling of superstructure and substructure behavior necessitates system-level analysis of *** seismic IAB studies have typically investigated the behavior of individual IAB components,however a gap of knowledge has developed due to the lack of studies and investigation about the behavior of all IAB components and their interactions with each other in a single analysis *** study uses nonlinear static and dynamic analyses to investigate and assess the seismic behavior of IABs typical to the state of *** analyses aim to bridge the gap of knowledge by evaluating IABs as a whole and utilizing the results to indicate potential vulnerabilities in the design and construction of IABs in Illinois during design-level and larger seismic events,which could not be identified by component-level IAB analyses alone.

关键词： structural analysis seismic design bridge design structural models seismic analysis

Defect detection in freight railcar tapered-roller bearings using vibration techniques

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Railway Engineering Science 2021年第1期29卷 42-58页

作者： Constantine Tarawneh Joseph Montalvo Brent Wilson University Transportation Center for Railway Safety(UTCRS) University of Texas Rio Grande Valley(UTRGV)EdinburgTXUSA Hum Industrial Technology IncSt.LouisMOUSA

Currently,there are two types of defect detection systems used to monitor the health of freight railcar bearings in service:wayside hot-box detection systems and trackside acoustic detection *** systems have proven to be inefficient in accurately determining bearing health,especially in the early stages of defect *** that end,a prototype onboard bearing condition monitoring system has been developed and validated through extensive laboratory testing and a designated field test in 2015 at the Transportation Technology Center,*** Pueblo,*** devised system can accurately and reliably characterize the health of bearings based on developed vibration thresholds and can identify defective taperedroller bearing components with defect areas smaller than 12.9 cm2 while in service.

关键词： Railcar health monitoring Onboard condition monitoring systems Bearing defect detection Bearing vibration signatures Bearing spectral analysis

Finite Element Modeling and Vibration Analysis of Sprag Clutch⁃Flexible Rotor System

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Journal of Harbin Institute of Technology(New Series) 2022年第2期29卷 13-23页

作者： Chuang Huang Yongqiang Zhao Guanghu Jin School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Gree Electric Appliances Inc.of ZhuhaiZhuhai 519070GuangdongChina National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To study the overall vibration characteristics of the sprag clutch⁃flexible rotor system(SC⁃FRS)under high⁃speed operating conditions,a finite element model of SC⁃FRS considering rotor flexibility and bearing support stiffness was established based on the proposed calculation method of the stiffness *** to this model,the natural frequency and mode shape of the system are calculated,and the correctness of the model was verified by comparing it with the calculation results of ANSYS *** the action of unbalance,the bending⁃torsion coupled vibration and the dynamic load of the inter⁃shaft bearings were analyzed,and it is found that the resonant peak in the torsional direction has the same resonance frequency as that in the bending direction.A test rig for the sprag clutch⁃rotor system was built,and the axis trajectory and critical speed were *** test results show that the finite element model of SC⁃FRS can accurately describe the vibration characteristics of the *** coupling vibration characteristics analysis of the sprag clutch⁃flexible rotor system can provide theoretical guidance for the dynamic design of the sprag clutch components.

关键词： sprag clutch⁃rotor system finite element model unbalanced mass experimental verification