ASTM_D_7917_-_14.pdf

Designation:D791714Standard Practice forInductive Wear Debris Sensors in Gearbox and DrivetrainApplications1This standard is issued under the fixed designation D7917;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONWear debris sensors,employing inductive sensing technologies(1,2),2are able to quantify weardebris to classify size and material composition(ferrous/non-ferrous)of metallic debris found inlubricating oil as a consequence of wear.Initial applications have been largely confined to industrialaero-derivative and aircraft gas turbine engine monitoring installations where the failure of high speedball and roller bearings results in significant secondary damage(2,3).With an almost exponentialgrowth in the wind turbine industry,one engineering issue still to be resolved is the unacceptablegearbox failure rate(4).Wear debris sensors can play an important role in understanding the variedbearing failure modes observed.There are thousands of inductive sensors operating in wind turbinesand other gearbox and drivetrain applications accruing millions of operational hours.While it isgenerally accepted that these sensors provide early warning of abnormal condition,the industry willbenefit from a standard practice for data usage and interpretation.1.Scope1.1 This practice covers the minimum requirements for anonline inductive sensor system to monitor ferromagnetic andnon-ferromagnetic metallic wear debris present in in-servicelubricating fluids residing in gearboxes and drivetrains.1.2 Metallic wear debris considered in this practice canrange in size from 40 m to greater than 1000 m of equivalentspherical diameter(ESD).1.3 This practice is suitable for use with the followinglubricants:industrial gear oils,petroleum crankcase oils,poly-alkylene glycol,polyol esters,and phosphate esters.1.4 This practice is for metallic wear debris detection,notoil cleanliness.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5.1 ExceptionSubsection 7.7 uses“Gs”.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:3D4175 Terminology Relating to Petroleum,PetroleumProducts,and LubricantsD7669 Guide for Practical Lubricant Condition Data TrendAnalysisD7685 Practice for In-Line,Full Flow,Inductive Sensor forFerromagnetic and Non-ferromagnetic Wear Debris De-termination and Diagnostics for Aero-Derivative and Air-craft Gas Turbine Engine BearingsD7720 Guide for Statistically Evaluating Measurand AlarmLimits when Using Oil Analysis to Monitor Equipmentand Oil for Fitness and ContaminationG40 Terminology Relating to Wear and Erosion2.2 ISO Standards:4ISO/TC 108 N 605 Terminology for the Field of ConditionMonitoring and Diagnostics of Machines1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts,Liquid Fuels,and Lubricants and is the direct responsibility of Subcom-mittee D02.96.07 on Integrated Testers,Instrumentation Techniques for In-ServiceLubricants.Current edition approved Oct.1,2014.Published November 2014.DOI:10.1520/D7917-14.2The boldface numbers in parentheses refer to the list of references at the end ofthis standard.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.4Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.Terminology3.1 Definitions:3.1.1 condition monitoring,na field of technical activityin which selected physical parameters associated with anoperating machine are periodically or continuously sensed,measured,and recorded for the interim purpose of reducing,analyzing,comparing,and displaying the data and informationso obtained,and for the ultimate purpose of using interim resultto support decisions related to the operation and maintenanceof the machine.3.1.2 equivalent spherical diameter(ESD),nthe equiva-lent spherical diameter of an irregularly shaped object is thediameter of a sphere of equivalent volume.3.1.2.1 DiscussionMetallic particles used to test and cali-brate inductive wear debris sensors are manufactured asspheres.A range of diameters,from smallest to largest sizesinvestigated,is utilized to vet the sensors capabilities andcalibr