Download or read book Effect of Silicon Nitride Balls and Rollers on Rolling Bearing Life written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-05-30 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three decades have passed since the introduction of silicon nitride rollers and balls into conventional rolling-element bearings. For a given applied load, the contact (Hertz) stress in a hybrid bearing will be higher than an all-steel rolling-element bearing. The silicon nitride rolling-element life as well as the lives of the steel races were used to determine the resultant bearing life of both hybrid and all-steel bearings. Life factors were determined and reported for hybrid bearings. Under nominal operating speeds, the resultant calculated lives of the deep-groove, angular-contact, and cylindrical roller hybrid bearings with races made of post-1960 bearing steel increased by factors of 3.7, 3.2, and 5.5, respectively, from those calculated using the Lundberg-Palmgren equations. An all-steel bearing under the same load will have a longer life than the equivalent hybrid bearing under the same conditions. Under these conditions, hybrid bearings are predicted to have a lower fatigue life than all-steel bearings by 58 percent for deep-groove bearings, 41 percent for angular-contact bearings, and 28 percent for cylindrical roller bearings.Zaretsky, Erwin V. and Vlcek, Brian L. and Hendricks, Robert C.Glenn Research CenterFATIGUE LIFE; ROLLER BEARINGS; ROLLERS; SILICON NITRIDES; SERVICE LIFE; PREDICTIONS; STRESSES

Download or read book Effect of Silicon Nitride Balls and Rollers on Rolling Bearing Life written by Erwin V. Zaretsky and published by BiblioGov. This book was released on 2013-06 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three decades have passed since the introduction of silicon nitride rollers and balls into conventional rolling-element bearings. For a given applied load, the contact (Hertz) stress in a hybrid bearing will be higher than an all-steel rolling-element bearing. The silicon nitride rolling-element life as well as the lives of the steel races were used to determine the resultant bearing life of both hybrid and all-steel bearings. Life factors were determined and reported for hybrid bearings. Under nominal operating speeds, the resultant calculated lives of the deep-groove, angular-contact, and cylindrical roller hybrid bearings with races made of post-1960 bearing steel increased by factors of 3.7, 3.2, and 5.5, respectively, from those calculated using the Lundberg-Palmgren equations. An all-steel bearing under the same load will have a longer life than the equivalent hybrid bearing under the same conditions. Under these conditions, hybrid bearings are predicted to have a lower fatigue life than all-steel bearings by 58 percent for deep-groove bearings, 41 percent for angular-contact bearings, and 28 percent for cylindrical roller bearings.

Download or read book Surface Endurance and Lubrication of Silicon Nitride Ball Bearings written by H. Dalal and published by . This book was released on 1975 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: A report is made on the effect of using silicon nitride balls on the rolling contact fatigue life of radially loaded M50 steel ball bearings. Scanning electron microscope (SEM) examination of the surface topography of as-manufactured silicon nitride ball surfaces is described and compared with silicon nitride ball and flat washer surfaces tested previously. The rolling-contact fatigue performance of previously tested all-tool-steel bearings is compared with the present group of bearings containing silicon nitride balls as well as with previously tested silicon nitride flat washers run against tool steel rollers. It is shown that the life of the present group of bearings is controlled by the life of the currently available silicon nitride ball complement. This is contrary to the previous flat washer life results. The ball groove surfaces of the present steel bearing rings after running against the silicon nitride balls is described.

Download or read book Life Adjustment Factors for Ball and Roller Bearings written by American Society of Mechanical Engineers. Rolling-Elements Committee and published by . This book was released on 1971 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Rolling element Fatigue Life of Silicon Nitride Balls written by Richard Jay Parker and published by . This book was released on 1974 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Surface and Mechanical Properties on Silicon Nitride Bearing Element Performance written by and published by . This book was released on 1975 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report discusses the importance of understanding the extent of surface damage caused during the manufacture of bearing surfaces on ceramics. The likely impact of the damaged surface on the usefulness of ceramics as rolling bearing materials is presented. The results of flat-washer rolling- contact fatigue tests signify the role of surface interactions in a steel- silicon nitride contact on the life of the contact. The variables evaluated include lubricant viscosity, surface finish of the silicon nitride washer, type of contact (line or point) and hardness of the steel rollers. The effect of the lower density and higher elastic modulus of silicon nitride on bearing fatigue life was analytically evaluated. The analysis shows that silicon nitride rolling elements can improve the fatigue life of very high speed bearings.

Download or read book Rolling Bearing Analysis 2 Volume Set written by Tedric A. Harris and published by CRC Press. This book was released on 2006-11-02 with total page 763 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the last four decades, Tedric Harris' Rolling Bearing Analysis has been the "bible" for engineers involved in rolling bearing technology. Why do so many students and practicing engineers rely on this book? The answer is simple: because of its complete coverage from low- to high-speed applications and full derivations of the underlying mathematics from a leader in the field. Updated, revamped, and reorganized for the new millennium, the fifth incarnation of this classic reference is the most modern, flexible, and interactive tool in the field. What makes this edition so revolutionary? For starters, the coverage is split conveniently into two books: Essential Concepts of Bearing Technology introduces the fundamentals involved in the use, design, and performance of rolling bearings for more common applications; Advanced Concepts of Bearing Technology delves into more advanced topics involving more dynamic loading, more extreme conditions, and higher-speed applications. Furthermore, each book in this edition includes a CD-ROM that contains numerical examples as well as tables of dimensional, mounting, and life-rating data obtained from ABMA/ANSI standards. Whether you are interested in the mathematics behind the empirical values or methods for estimating the effects of complex stresses on fatigue endurance, Rolling Bearing Analysis, Fifth Edition compiles the techniques and the data that you need in a single, authoritative resource.

Download or read book Advanced Concepts of Bearing Technology written by Tedric A. Harris and published by CRC Press. This book was released on 2006-10-09 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part of the fifth edition of the classic Rolling Bearing Analysis, this book examines bearing performance and service life for more complex loading, more extreme operating conditions, and higher-speed applications. Several topics are unique to this work, including mathematical relationships for internal load distribution under conditions of high speed, combined radial, axial, and moment loading, as well as the effects of various types of profiling. The authors also delve into the mathematical development of rolling element-raceway lubricant film thickness and contact friction, the stress-life method for calculating bearing fatigue, and the effects of shaft and supporting structure flexure on bearing loading and deflection.

Download or read book NASA Technical Note written by and published by . This book was released on 1976 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Grease Lubrication in Rolling Bearings written by Piet M. Lugt and published by John Wiley & Sons. This book was released on 2013-02-18 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: The definitive book on the science of grease lubrication for roller and needle bearings in industrial and vehicle engineering. Grease Lubrication in Rolling Bearings provides an overview of the existing knowledge on the various aspects of grease lubrication (including lubrication systems) and the state of the art models that exist today. The book reviews the physical and chemical aspects of grease lubrication, primarily directed towards lubrication of rolling bearings. The first part of the book covers grease composition, properties and rheology, including thermal and dynamics properties. Later chapters cover the dynamics of greased bearings, including grease life, bearing life, reliability and testing. The final chapter covers lubrications systems – the systems that deliver grease to the components requiring lubrication. Grease Lubrication in Rolling Bearings: Describes the underlying physical and chemical properties of grease. Discusses the effect of load, speed, temperature, bearing geometry, bearing materials and grease type on bearing wear. Covers both bearing and grease performance, including thermo-mechanical ageing and testing methodologies. It is intended for researchers and engineers in the petro-chemical and bearing industry, industries related to this (e.g. wind turbine industry, automotive industry) and for application engineers. It will also be of interest for teaching in post-graduate courses.

Download or read book ASME Technical Papers written by and published by . This book was released on 1999 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Reevaluation of the Stress life Relation in Rolling element Bearings written by Richard Jay Parker and published by . This book was released on 1972 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Four groups of 12.7 millimeter diameter vacuum-degassed AISI 52100 balls were tested, each at a maximum Hertz stress in the range of 4.5 times 10 to 9th power to 6.0 times 10 to 9th power N/m2. Tests were run in the five-ball fatigue tester at a contact angle of 30 deg and a shaft speed of 10,000 rpm. The 10 percent fatigue lives at the four stress levels indicated that fatigue life is inversely proportional to maximum Hertz stress raised to the power of 12. This result agrees with a survey of the literature which suggests that a stress-life exponent of approximately 12 is typical of vacuum-processed bearing steels rather than the exponent of 9 which has been generally accepted by the bearing industry.

Download or read book Rolling Bearing Analysis written by Tedric A. Harris and published by Wiley-Interscience. This book was released on 1991-04-17 with total page 1050 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book fills a need in the literature by presenting a unified, up-to-date approach to the analysis of rolling bearing performance and is aimed at developing a basic understanding of rolling bearing operation. Going beyond the earlier editions, this Third Edition explores in greater detail such topics as materials, methods of testing and evaluation of test data, methods of lubrication and their usages. Also covers the initial development of a substantially improved and more accurate fatigue life theory. To accomplish this, early chapters discuss the simplest elements of rolling bearings such as basic bearing types, geometry, loading of single balls and rollers, contract stresses and deformations. Following this complex analysis of load distribution among the rolling elements, speeds and velocities, elastohydrodynamic lubrication, statistics of bearing endurance, fatigue life, friction and temperature are considered. Examples are included to clarify and highlight important concepts.

Download or read book Applied Tribology written by Michael M. Khonsari and published by John Wiley & Sons. This book was released on 2008-04-30 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applications of tribological technology in bearings are wide and varied in industries ranging from aerospace, marine and automotive to power, process, petrochemical and construction. Applied Tribology, 2nd edition not only covers tribology in bearings but demonstrates the same principles for other machine components, such as piston pins, piston rings and hydrostatic lifts, as well as in more recent technologies such as gas bearings in high-speed machines and computer read-write devices. Maintaining a balance between theoretical analysis and practical experience with co-authors from academia and industry, this new edition is significantly revised and expanded with new material. Features include; • Two brand new chapters on seals and bearing failure modes and bearing health monitoring techniques • Coverage of new developments in full-film, dry, and partial lubrication; gas bearings; and ball and roller bearings • Design guides based on full Reynolds equation that enable accurate prediction of load capacity, power loss, temperature rise • Comprehensive presentation of important design factors involving material and lubricants. • State-of-the-art presentation and up-to-date references of pertinent scientific and applied topics in tribology • Numerous examples that reinforce the understanding of concepts and provide procedures for the design and performance analysis of components Applied Tribology, 2nd edition provides a valuable and authoritative resource for mechanical engineering professionals working in a wide range of industries with machinery including turbines, compressors, motors, electrical appliances & electronic components. Senior and graduate students in mechanical engineering will also find it a useful text and reference.

Download or read book Silicon Nitride in Rolling Contact Bearings written by H. Robert Baumgartner and published by . This book was released on 1975 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: The program (1) investigated silicon nitride material characteristics in relation to bearing performance and (2) endurance tested bearings containint silicon nitride components. Six hot-pressed silicon nitride compositional variations were prepared, characterized and evaluated in rolling contact fatigue (RCF). All ceramic fatigue lives equalled or exceeded the fatigue life of M-50 steel at the 325 pound load. A stress corrosion mechanism is used to explain the time dependent ceramic fatigue behavior and life differences are attributed to differences in slow crack growth rates. Ten precision, 60 mm bore, roller bearings, containing silicon nitride rollers, steel races and retainer, were designed, fabricated and endurance tested at a radial load of 5050 pounds and shaft speed of AFBMA calculated L(10) life of 21.6 hours for a similar all steel bearing.

Download or read book Rolling Bearing Analysis Advanced concepts of bearing technology written by Tedric A. Harris and published by . This book was released on 2006 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Efficiency in Motor Systems written by Paolo Bertoldi and published by Springer Nature. This book was released on 2021-09-24 with total page 748 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains selected, peer-reviewed papers presented at the 11th International Conference on Energy Efficiency in Motor Systems (EEMODS'19), held in Tokyo, Japan from 17-19 September 2019. As with previous conferences in this series, EEMODS’19 provided a scientific forum to discuss and debate the latest developments and impacts of electrical motor systems on energy and the environment, energy efficiency policies and programmes adopted and planned, standards (including ISO 50.001), and the technical and commercial advances made in the dissemination and penetration of energy-efficient motor systems. Topics covered include: technologies, research and innovation in the areas of electric motors from life cycle costing to 3D printing to artificial intelligence/machine learning-based monitoring systems; emerging motor technologies; power electronics and drives; pump systems, including life cycle costing, energy efficiency improvements, maintenance, and operation for industrial, water supply and treatment, building, and irrigation; compressed air systems; fans /exhaust systems; refrigeration systems maintenance and operation; mechanical power transmission; motors in household appliances and HVAC (residential and commercial); motors and drives for transport applications including policies, programmes, regulation, and international standards; industrial management policies and standards; motor system audit and verification; policies, programmes and financing: analysis of motor system energy use and greenhouse gas emissions for motor systems, e-vehicles and related charging infrastructure; harmonization of global motor efficiency test standards; evaluation of utility programmes for improving energy efficiency in motor systems; and policy implementation, market surveillance and enforcement mechanisms, including case studies. The conference is international by nature and aims to attract high quality and innovative contributions from all corners of the globe, while the papers facilitate the development of new technologies, policies and strategies to increase energy efficiency.