Download or read book An Experimental Study of Scuffing Performance of a Helical Gear Pair Subjected to Different Lubrication Methods written by Rohit Matthew Abraham and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Lubrication systems used in gear trains are intended to serve two distinct purposes: (i) provide the quantities of oil to gear mesh contact interfaces to allow formation of a healthy elastohydrodynamic fluid film and (ii) help remove heat generated at gear mesh contact interfaces. Failure of the lubrication system in either of these tasks often results in a temperature induced contact failure, called scuffing. This study investigates the effectiveness of various lubrication methods in preventing scuffing. A new high-speed gear test set-up is developed specifically for investigating the scuffing performance of high-speed, high-load helical gears operating at realistic oil temperature conditions. The objective of this study is to experimentally characterize the scuffing performance of the helical gears as a function of various lubrication methods and parameters defining each method. Sets of scuffing experiments are performed using the test methodology developed and lubrication methods that successfully prevented scuffing of the gears are identified. The test matrix includes two different automotive drivetrain lubricants and different lubrication methods of forced (jet) lubrication, dip lubrication and mist lubrication. The test specimens consist of gears having three surface finishes, (i) ground-honed gears which were identified as the baseline, (ii) super-finished gears and (iii) phosphate coated gears. The effects of parameters such as jet flow rate, jet velocity and impingement depth on scuffing are investigated and tabulated using the results from the jet lubricated tests. The impact of gear micro-geometry and edge-loading effects on scuffing initiation are also investigated.

Download or read book An Experimental Study on the Effects of Debris Damage on Scuffing Performance of Spur Gear Pairs written by Tiffany Wen Roe Lim and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, a test methodology was developed to induce debris to the gear tooth profiles during the operation of a gear pair. This methodology was applied to a number of spur gear specimens for different types, quantities and sizes of debris particles. The extent of surface damage due to application of debris was documented and related to the sizes, types and quantities of debris applied. A high-speed and high-temperature test machine was used to put gears with varying severity of debris damage through a staged scuffing test to investigate the influence of such damage on scuffing outcome. While selected damage sites monitored during staged scuffing tests did not exhibit any progression to be identified as initiation sites for scuffing failure, gears with no or little debris damage were shown to pass the scuffing test while gears with heavier debris damage scuffed consistently. As such, the results of this study show conclusively that there is a direct correlation between severity of the debris damage and resultant scuffing performance of the gears.

Download or read book An Experimental Study on the Scuffing Performance of High power Spur Gears at Elevated Oil Temperatures written by James Walter Brenneman and published by . This book was released on 2013 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: In this study, a number of spur gear tests were performed under high-power and high-temperature conditions representative of certain aerospace gearing applications. As the first type of tests, long cycle tests of 100 million cycles were performed at set operating speed, load, and temperature conditions. The second type of tests, load-staged scuffing tests, implemented an incrementally increased torque schedule under constant speed and oil temperature conditions. Two different gear tooth surfaces were considered in these tests: hard ground surfaces representative of rough, as machined gear surfaces and chemically polished gear surfaces that were an order of magnitude smoother than the ground surfaces. The primary failure mode of concern was scuffing of the contact surfaces due to temperature build up. The impact of surface roughness amplitudes, contact stress, and oil inlet temperature on scuffing failures were investigated. Effects of ramp up procedures for the speed and torque, as well as the introduction of a break-in test stage were also investigated to show that they are critical to the scuffing performance of gears.

Download or read book Handotai shuseki kairo gijutsu shinpojiumu 27 written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Study Ofl the Effect of Lubricant Temperature and Pressure on Scuffing written by Huanliang Chen and published by . This book was released on 1993 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book JSME International Journal written by and published by . This book was released on 1995 with total page 1388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The New Methods for Scuffing and Pitting Investigation of Coated Materials for Heavy Loaded Lubricated Elements written by Remigiusz Michalczewski and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Influence of a Class of Surface Defects on the High speed Scuffing Performance of Spur Gears written by Gunther Shepard Beall and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gear teeth experience contact conditions that vary continuously as they pass through the meshing zone. Thus, not only the sizes but also the positions of surface defects become critical to their scuffing survivability. High-speed gearbox cost and reliability can be improved by quantifying these features and determining their impact on scuffing performance. Pursuant to this, representative defects in the form of scratches are applied in two batches to the contacting surfaces of high-quality spur gear specimens. These, along with an undamaged baseline gear pair, are then tested through a staged scuffing matrix incrementally increasing the operating load, speed, and lubricant temperature. Metrological procedures developed to quantify scratch parameters and track surface damage are used initially and throughout testing to document evolvement of the surfaces. It is concluded that (i) larger scratches generally decrease scuffing performance, (ii) the location of scratches is critical to scuffing performance; scuffing was never observed in areas where sliding velocities were low, (iii) increased wear and heat generation are observed on defects in high-sliding regions, and (iv) wear and tribo-film formation improve the scuffing performance of scratched gears. In addition, thermal elastohydrodynamic lubrication simulations are performed to confirm that increasing scratch width and surface sliding velocities have the most influence on increasing the lubricant flash temperatures.

Download or read book Analysis of Helical Gear Performance Under Elastohydrodynamic Lubrication written by Hazim Jamali and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Friction and Lubrication written by Robert Henry Thurston and published by . This book was released on 1879 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On the Correlation of Specific Film Thickness and Gear Pitting Life written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-13 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of the lubrication regime on gear performance has been recognized, qualitatively, for decades. Often the lubrication regime is characterized by the specific film thickness defined as the ratio of lubricant film thickness to the composite surface roughness. It can be difficult to combine results of studies to create a cohesive and comprehensive dataset. In this work gear surface fatigue lives for a wide range of specific film values were studied using tests done with common rigs, speeds, lubricant temperatures, and test procedures. This study includes previously reported data, results of an additional 50 tests, and detailed information from lab notes and tested gears. The dataset comprised 258 tests covering specific film values (0.47 to 5.2). The experimentally determined surface fatigue lives, quantified as 10-percent life estimates, ranged from 8.7 to 86.8 million cycles. The trend is one of increasing life for increasing specific film. The trend is nonlinear. The observed trends were found to be in good agreement with data and recommended practice for gears and bearings. The results obtained will perhaps allow for the specific film parameter to be used with more confidence and precision to assess gear surface fatigue for purpose of design, rating, and technology development. Krantz, Timothy L. Glenn Research Center WBS 380046.02.03.02.02.01

Download or read book Gear Lubrication written by Institute of Petroleum (Great Britain). Lubricants and Waxes Subcommittee. Mechanical Tests of Lubricants Panel and published by . This book was released on 1966 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Symposium on Industrial Gear Lubricants written by American Society for Testing Materials. Committee D-2 on Petroleum Products and Lubricants and published by . This book was released on 1949 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This symposium was sponsored by Section U-III on Industrial Gear Oils, of Technical Committee B, and was arranged by a special symposium committee. The symposium was introduced by Mr. G.L. Sumner, Chairman, Westinghouse Electric Corp., who stated that the papers cover studies of various field problems encountered in the lubrication of industrial gears. He also explained that the information, experiences, and data presented by the authors and discussors of the papers are intended to be used by the committee as a guide in determining which properties of industrial gear lubricants should be investigated for standardization of test methods, establishment of nomenclature and definitions, and preparation of specifications."--Foreword.

Download or read book An Experimental Investigation of the Influence of the Lubricant Viscosity and Additives on Gear Wear written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of lubricant viscosity and additives on the average wear rate of spur gear pairs was investigated experimentally. The gear specimens of a comprehensive gear durability test program that made use of seven lubricants covering a range of viscosities were examined to measure gear tooth wear. The measured wear was related to the as-manufactured surface roughness, the elastohydrodynamic film thickness, and the experimentally determined contact fatigue lives of the same specimens. In general, the wear rate was found to be inversely proportional to the viscosity of the lubricant and to the lambda ratio (also sometimes called the specific film thickness). The data also show an exponential trend between the average wear rates and the surface fatigue lives. Lubricants with similar viscosities but differing additives and compositions had somewhat differing gear surface fatigue lives and wear rates. Krantz, Timothy L. and Kahraman, Ahmet Glenn Research Center NASA/TM-2005-213956, ARL-TR-3126, E-15272

Download or read book A Study of the Effect of Lubricating Oil on the Thermal Horsepower Capacity of a Helical Gear Speed Increaser written by Walter Joseph Honigsberger and published by . This book was released on 1950 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Finishing of Conical Gears by Pulsed Electrochemical Honing written by Neelesh K Jain and published by Cambridge Scholars Publishing. This book was released on 2019-06-04 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book sheds light on the development of Pulsed-Electrochemical Honing (PECH), a unique hybrid finishing process, which has capabilities of finishing intricate shaped components (especially gears). The text covers the fundamentals of the process, and details all parameters of PECH in the finishing of straight bevel gears. It discusses all important aspects of electrochemical honing, and details recent developments in tools, technologies, controls and operations.

Download or read book Lubrication System Failure Baseline Testing on an Aerospace Quality Gear Mesh written by Robert F. Handschuh and published by . This book was released on 2000 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerospace drive systems are required to survive a loss-of-lubrication test for qualification. In many cases emergency lubrication systems need to be designed and utilized to permit the drive system to pass this difficult requirement. The weight of emergency systems can adversely affect the mission capabilities of the aircraft. The possibility to reduce the emergency system weight through the use of mist lubrication will be described. Mist lubrication involves the delivery of a minute amount of an organic liquid as a vapor or fine mist in flowing compressed air to rubbing surfaces. At the rubbing surface, the vapor or mist reacts to form a solid lubricating film. The aim of this study was to establish a baseline for gear behavior under oil depleted conditions. A reactive vapor-mist lubrication method is described and proposed as a candidate emergency lubrication system.