ASTM_D_7418_-_21.pdf

Designation:D741821Standard Practice forSet-Up and Operation of Fourier Transform Infrared(FT-IR)Spectrometers for In-Service Oil Condition Monitoring1This standard is issued under the fixed designation D7418;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.INTRODUCTIONThis practice describes the instrument set-up and operation parameters for using FT-IR spectrom-eters for in-service oil condition monitoring.The following parameters are typically monitored forpetroleum and hydrocarbon based lubricants:water,soot,oxidation,nitration,phosphate antiwearadditives,fuel dilution(gasoline or diesel),sulfate by-products and ethylene glycol.Measurement anddata interpretation parameters are standardized to allow operators of different FT-IR spectrometers toobtain comparable results by employing the same techniques.Two approaches may be used to monitorin-service oil samples by FT-IR spectrometry:(1)direct trend analysis and(2)differential(spectralsubtraction)trend analysis.The former involves measurements made directly on in-service oilsamples,whereas the latter involves measurements obtained after the spectrum of a reference oil hasbeen subtracted from the spectrum of the in-service oil being analyzed.Both of these approaches aredescribed in this practice,and it is up to the user to determine which approach is more appropriate.1.Scope*1.1 This practice covers the instrument set-up and operationparameters for using FT-IR spectrometers for in-service oilcondition monitoring for both direct trend analysis and differ-ential trend analysis approaches.1.2 This practice describes how to acquire the FT-IR spec-trum of an in-service oil sample using a standard transmissioncell and establishes maximum allowable spectral noise levels.1.3 Measurement and integrated parameters for individualin-service oil condition monitoring components and param-eters are not described in this practice and are described in theirrespective test methods.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum Products,LiquidFuels,and LubricantsE131 Terminology Relating to Molecular SpectroscopyE168 Practices for General Techniques of Infrared Quanti-tative AnalysisE1421 Practice for Describing and Measuring Performanceof Fourier Transform Mid-Infrared(FT-MIR)Spectrom-eters:Level Zero and Level One TestsE1866 Guide for Establishing Spectrophotometer Perfor-mance Tests3.Terminology3.1 Definitions:1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts,Liquid Fuels,and Lubricants and is the direct responsibility of Subcom-mittee D02.96.03 on FTIR Testing Practices and Techniques Related to In-ServiceLubricants.Current edition approved Dec.1,2021.Published January 2022.Originallyapproved in 2007.Last previous edition approved in 2020 as D7418 20.DOI:10.1520/D7418-21.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.13.1.1 For definitions of terms used in this standard,seeTerminology D4175.3.1.2 For definitions of terms relating to infrared spectros-copy used in this practice,refer to Terminology E131.3.1.3 Fourier transform infrared(FT-IR)spectrometry,nform of infrared spectrometry in which an interferogram isobtained;this interferogram is then subjected to a Fouriertransform calculation to obtain an amplitude