EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Evaluation of an In Situ  Liquid Lubrication System for Space Mechanisms Using a Vacuum Spiral Orbit Tribometer

Download or read book Evaluation of an In Situ Liquid Lubrication System for Space Mechanisms Using a Vacuum Spiral Orbit Tribometer written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-19 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many moving mechanical assemblies (MMAs) for space applications rely on a small, initial charge of lubricant for the entire mission lifetime, often in excess of five years. In many cases, the premature failure of a lubricated component can result in mission failure. If lubricant could be resupplied to the contact in-situ, the life of the MMA could be extended. A vacuum spiral orbit tribometer (SOT) was modified to accept a device to supply re-lubrication during testing. It was successfully demonstrated that a liquid lubricant (Pennzane (Registered Trademark)/Nye 2001A) could be evaporated into a contact during operation, lowering the friction coefficient and therefore extending the life of the system. Jansen, Mark J. and Jones, William R., Jr. and Pepper, Stephen V. Glenn Research Center NASA/TM-2002-211683, NAS 1.15:211683, E-13411

Book Preliminary Evaluation of Greases for Space Mechanisms Using a Vacuum Spiral Orbit Tribometer

Download or read book Preliminary Evaluation of Greases for Space Mechanisms Using a Vacuum Spiral Orbit Tribometer written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-20 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most currently used greases for space applications are based on perfluoropolyalkylethers (PFPE) and multiply alkylated cyclopentane (MAC) oils. Evaluation of the greases includes outgassing properties, rheological behavior, and particularly the ability to create EHL films under conditions as close as possible to an actual application. A spiral orbit tribometer (SOT) has been developed to conduct accelerated tests under realistic conditions. The SOT was employed to evaluate two greases used in space mechanisms: a PFPE oil with polytetrafluoroethylene (PTFE) thickener, and a multiply alkylated cyclopentane oil with n-octadecylterephthalamate soap. The results from the greases are in agreement with results previously obtained with the base oils. Marchetti, Mario and Jones, William R., Jr. and Street, Kenneth W. and Pepper, Stephen V. and Jansen, Mark J. Glenn Research Center NASA/TM-2001-211157, E-13013, NAS 1.15:211157

Book Solid Lubricants and Self Lubricating Solids

Download or read book Solid Lubricants and Self Lubricating Solids written by Francis J. Clauss and published by Elsevier. This book was released on 2012-12-02 with total page 279 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solid Lubricants and Self-Lubricating Solids provides a concise treatment of solid lubricants and self-lubricating solids and their applications. These solid lubricants include graphite, molybdenum disulfide, plastics and thermoplastics, nylon, soft metals, fluorocarbons, and phenolics. Low-friction inorganic solids as well as miscellaneous inorganic compounds such as dichalcogenides and fluorides are also discussed. This book is comprised of 11 chapters and begins with an overview of some basic facts about friction and lubrication. The reader is then introduced to inorganic solid lubricants, their their crystal structure, advantages and disadvantages, and the forms in which they are most commonly used. The following chapters focus on the lubricating qualities of graphite, molybdenum disulfide, plastics and thermoplastics, nylon, soft metals, and fluorocarbons. Miscellaneous inorganic compounds with special applications involving friction and wear are also considered. The final chapter is devoted to phenolic laminates, their properties, and their mechanical applications such as gears and bearings. This monograph will be a useful resource for designers and operating engineers.

Book A New Apparatus to Evaluate Lubricants for Space Applications

Download or read book A New Apparatus to Evaluate Lubricants for Space Applications written by and published by . This book was released on 2000 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lubricants used in space mechanisms must be throughly tested prior to their selection for critical applications. Traditionally, two types of tests have been used: accelerated and full scale. Accelerated tests are rapid, economical, and provide useful information for gross screening of candidate lubricants. Although full-scale tests are more believeable because they mimic actual spacecraft conditions, they are expensive and time consuming. The spiral orbit tribometer compromises between the two extremes. It rapidly determines the rate of tribochemically induced lubricant consumption, which leads to finite test times, under realistic rolling/pivoting conditions that occur in angular contact bearings.

Book Performance and Durability of High Temperature Foil Air Bearings for Oil Free Turbomachinery

Download or read book Performance and Durability of High Temperature Foil Air Bearings for Oil Free Turbomachinery written by C. DellaCorte and published by . This book was released on 2000 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance and durability of advanced, high temperature foil air bearings are evaluated under a wide range (10-50 kPa) of loads at temperatures from 25 to 650 deg C. The bearings are made from uncoated nickel based superalloy foils. The foil surface experiences sliding contact with the shaft during initial start/stop operation. To reduce friction and wear, the solid lubricant coating, PS 304, is applied to the shaft by plasma spraying. PS304 is a NiCr based Cr2O3 coating with silver and barium fluoride/calcium fluoride solid lubricant additions. The results show that the bearings provide lives well in excess of 30,000 cycles under all of the conditions tested. Several bearings exhibited lives in excess of 100,000 cycles. Wear is a linear function of the bearing load. The excellent performance measured in this study suggests that these bearings and the PS 304 coating are well suited for advanced high temperature, oil-free turbomachinery applications.

Book Spacecraft Systems Engineering

Download or read book Spacecraft Systems Engineering written by Peter Fortescue and published by Wiley. This book was released on 2003 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following on from the hugely successful previous editions, the third edition of Spacecraft Systems Engineering incorporates the most recent technological advances in spacecraft and satellite engineering. With emphasis on recent developments in space activities, this new edition has been completely revised. Every chapter has been updated and rewritten by an expert engineer in the field, with emphasis on the bus rather than the payload. Encompassing the fundamentals of spacecraft engineering, the book begins with front-end system-level issues, such as environment, mission analysis and system engineering, and progresses to a detailed examination of subsystem elements which represent the core of spacecraft design - mechanical, electrical, propulsion, thermal, control etc. This quantitative treatment is supplemented by an appreciation of the interactions between the elements, which deeply influence the process of spacecraft systems design. In particular the revised text includes * A new chapter on small satellites engineering and applications which has been contributed by two internationally-recognised experts, with insights into small satellite systems engineering. * Additions to the mission analysis chapter, treating issues of aero-manouevring, constellation design and small body missions. In summary, this is an outstanding textbook for aerospace engineering and design students, and offers essential reading for spacecraft engineers, designers and research scientists. The comprehensive approach provides an invaluable resource to spacecraft manufacturers and agencies across the world.

Book Space Vehicle Mechanisms

Download or read book Space Vehicle Mechanisms written by Peter L. Conley and published by John Wiley & Sons. This book was released on 1998-02-27 with total page 814 pages. Available in PDF, EPUB and Kindle. Book excerpt: Die Entwicklung von Weltraumfahrzeugen ist ein Industriezweig, der in den vergangenen drei Jahrzehnten beständig gewachsen ist. Heute ist es eine komplexe technische, internationale Branche. Dieses Buch vermittelt Informationen über alle Mechanismen von Weltraumfahrzeugen. Spitzenexperten auf diesem Gebiet, die in verschiedenen Disziplinen zu Hause sind, haben einen wichtigen Beitrag hierzu geleistet. Das Buch ist in drei Teile untergliedert: Grundlagen und technische Eigenschaften wichtiger Materialien; Entwicklung und Verhalten kritischer Komponenten und eine Einführung in Fahrzeugniveau-Analysen und Integrationstechniken. (01/98)

Book Fundamentals of Space Systems

Download or read book Fundamentals of Space Systems written by Vincent L. Pisacane and published by Johns Hopkins University Appli. This book was released on 2005 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Space Systems was developed to satisfy two objectives: the first is to provide a text suitable for use in an advanced undergraduate or beginning graduate course in both space systems engineering and space system design. The second is to be a primer and reference book for space professionals wishing to broaden their capabilities to develop, manage the development, or operate space systems. The authors of the individual chapters are practicing engineers that have had extensive experience in developing sophisticated experimental and operational spacecraft systems in addition to having experience teaching the subject material. The text presents the fundamentals of all the subsystems of a spacecraft missions and includes illustrative examples drawn from actual experience to enhance the learning experience. It includes a chapter on each of the relevant major disciplines and subsystems including space systems engineering, space environment, astrodynamics, propulsion and flight mechanics, attitude determination and control, power systems, thermal control, configuration management and structures, communications, command and telemetry, data processing, embedded flight software, survuvability and reliability, integration and test, mission operations, and the initial conceptual design of a typical small spacecraft mission.

Book Friction Science and Technology

Download or read book Friction Science and Technology written by Peter J. Blau and published by CRC Press. This book was released on 2008-10-20 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Should have broad appeal in many kinds of industry, ranging from automotive to computers-basically any organization concerned with products having moving parts!"-David A. Rigney, Materials Science and Engineering Department, Ohio State University, Columbus, USAIn-Depth Coverage of Frictional ConceptsFriction affects so many aspects of daily l

Book Relative Lifetimes of Several Space Liquid Lubricants Using a Vacuum Spiral Orbit Tribometer  sot      Nasa

Download or read book Relative Lifetimes of Several Space Liquid Lubricants Using a Vacuum Spiral Orbit Tribometer sot Nasa written by United States. National Aeronautics and Space Administration and published by . This book was released on 2003* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Historic Scientific Instruments in Denmark

Download or read book Historic Scientific Instruments in Denmark written by Hemming Andersen and published by Kgl. Danske Videnskabernes Selskab. This book was released on 1996 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Chemistry and Technology of Lubricants

Download or read book Chemistry and Technology of Lubricants written by R. M. Mortier and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use oflubricants began in ancient times and has developed into a major international business through the need to lubricate machines of increasing complexity. The impetus for lubricant development has arisen from need, so lubricatingpractice has precededan understandingofthescientificprinciples. This is not surprising as the scientific basis of the technology is, by nature, highly complex and interdisciplinary. However, we believe that the under standing of lubricant phenomena will continue to be developed at a mol ecular level to meet future challenges. These challenges will include the control of emissions from internal combustion engines, the reduction of friction and wear in machinery, and continuing improvements to lubricant performanceand life-time. More recently, there has been an increased understanding ofthe chemical aspects of lubrication, which has complemented the knowledge and under standing gained through studies dealing with physics and engineering. This book aims to bring together this chemical information and present it in a practical way. It is written by chemists who are authorities in the various specialisations within the lubricating industry, and is intended to be of interest to chemists who may already be working in the lubricating industry or in academia, and who are seeking a chemist's view of lubrication. It will also be of benefit to engineers and technologists familiar with the industry who requirea more fundamental understanding oflubricants.

Book Science and Application of Nanotubes

Download or read book Science and Application of Nanotubes written by D. Tománek and published by Springer Science & Business Media. This book was released on 2005-12-17 with total page 393 pages. Available in PDF, EPUB and Kindle. Book excerpt: This series of books, which is published at the rate of about one per year, addresses fundamental problems in materials science. The contents cover a broad range of topics from small clusters of atoms to engineering materials and involve chemistry, physics, materials science, and engineering, with length scales ranging from Ångstroms up to millimeters. The emphasis is on basic science rather than on applications. Each book focuses on a single area of current interest and brings together leading experts to give an up-to-date discussion of their work and the work of others. Each article contains enough references that the interested reader can access the relevant literature. Thanks are given to the Center for Fundamental Materials Research at Michigan State University for supporting this series. M. F. Thorpe, Series Editor E-mail: thorpe@pa. msu. edu East Lansing, Michigan V PREFACE It is hard to believe that not quite ten years ago, namely in 1991, nanotubes of carbon were discovered by Sumio Iijima in deposits on the electrodes of the same carbon arc apparatus that was used to produce fullerenes such as the “buckyball”. Nanotubes of carbon or other materials, consisting ofhollow cylinders that are only a few nanometers in diameter, yet up to millimeters long, are amazing structures that self-assemble under extreme conditions. Their quasi-one-dimensional character and virtual absence of atomic defects give rise to a plethora of unusual phenomena.

Book Solid Lubrication Fundamentals and Applications

Download or read book Solid Lubrication Fundamentals and Applications written by Kazuhisa Miyoshi and published by CRC Press. This book was released on 2019-06-05 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solid Lubrication Fundamentals and Applications description of the adhesion, friction, abrasion, and wear behavior of solid film lubricants and related tribological materials, including diamond and diamond-like solid films. The book details the properties of solid surfaces, clean surfaces, and contaminated surfaces as well as discussing the structu