\ f~~\ l.r-J TteEngineering =3 400 COMMONWEALTH DRIVE WARRENDALE, PA 15096 !-■-■■ ■.V.l!V,^-:-,l=>-J --.-■-H^ ^V -,:..-,-,., , ,-■- Vx-„ - ^-v ■-.,,. -V, .■-,-::-,-,-.-.,/ -J-, - -.-. „-:!, ..-A-.i ,V -..g-W.-.^ ? ■-:■,-. -:~'-;. '-,-■-■- ■-.-'.. Extending Bearing Life go Off-Highway Equipment Walter P„ Waskiewicz Fafnir Bearing Div. of Textron Inc. International Off-Highway & Powerplant Congress & Exposition Milwaukee, Wisconsin September 10-13,1984 Downloaded from SAE International by University of Leeds, Saturday, August 11, 2018The appearance of the code at the bottom of the first page of this paper indicates SAE's consent that copies of the paper may be made for persona! or interne! use, or for the personal or internal use of specific clients. This consent is given on the con­ dition, however, that the copier pay the stated per article copy fee through the Copyright Clearance Center, Inc., Operations Center, P.O. Box 765, Schenectady, N.Y. 12301, for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. Papers published prior to 1978 may also be copied at a per paper fee of $2.50 under the above stated conditions. SAE routinely stocks printed papers for a period of three years following date of publication. Direct your orders to SAE Order Department. To obtain quantity reprint rates, permission to reprint a technical paper or per­ mission to use copyrighted SAE publications in other works, contact the SAE Publications Division. ISSN 0148-7191 Copyright © 1984 Society of Automotive Engineers, Inc. This paper is subject to revision. Statements and opinions ad- Persons wishing to submit papers to be considered for pre- vanced in papers or discussion are the author's and are his sentation or publication through SAE should send the manu- responsibility, not SAE's; however, the paper has been edited script or a 300 word abstract of a proposed manuscript to: by SAE for uniform styling and format. Discussion will be Secretary, Engineering Activity Board, SAE. printed with the paper if it is published in SAE Transactions. lor permission to publish this paper in full or in part, contact Printed in U.S.A. the SAE Publications Division. Downloaded from SAE International by University of Leeds, Saturday, August 11, 2018Walter P. Waskiewicz Fafnir Bearing Div. of Textron Inc. ABSTRACT A thin dense chromium coating has been de­ veloped that extends bearing life, particularly in prob­ lem environments. The coating possesses exceptional adhesion to the base metal, which allows it to withstand the extremely high unit loads present in bearing race­ ways. In conventional bearings life typically ends due to wear or an ultimate material failure in the raceway or rolling element. The actual cause of the failure can stem from many factors. Corrosion, contamination, loss of or poor lubrication, and mechanical damage, all accelerate failure. The coating reduces the detrimental impact of these factors, thus extending bearing life. EXTENDING BEARING LIFE IN OFF-HIGHWAY EQUIPMENT BEARING LIFE should be defined not merely as rolling contact fatigue life, but the total length of time, starting with the date of shipment, through storage prior to installation, plus operating life until such time as it no longer meets the requirements of the application. Fai­ lure may not be the traditional race or rolling element macro-spalling fatigue that develops from surface or sub-surface micro-cracks. Failure can occur when the bearing has worn to the degree that the application cannot tolerate the resulting looseness. In addition, premature and sudden failures occur when operating conditions are changed by extraordinary cir­ cumstances, such as loss of lubrication, injestion o