1、Designation: D7414 09D7414 18Standard Test Method forCondition Monitoring of Oxidation in In-Service Petroleumand Hydrocarbon Based Lubricants by Trend AnalysisUsing Fourier Transform Infrared (FT-IR) Spectrometry1This standard is issued under the fixed designation D7414; the number immediately foll
2、owing 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.1. Scope Scope*1.1 This test
3、 method covers monitoring oxidation in in-service petroleum and hydrocarbon based lubricants such as in dieselcrankcase, motor, hydraulic, gear and compressor oils, as well as other types of lubricants that are prone to oxidation.1.2 This test method uses Fourier Transform Infrared (FT-IR) spectrome
4、try for monitoring build-up of oxidation products inin-service petroleum and hydrocarbon based lubricants as a result of normal machinery operation. Petroleum and hydrocarbonbased lubricants react with oxygen in the air to form a number of different chemical species, including aldehydes, ketones, es
5、ters,and carboxylic acids. This test method is designed as a fast, simple spectroscopic check for monitoring of oxidation in in-servicepetroleum and hydrocarbon based lubricants with the objective of helping diagnose the operational condition of the machine basedon measuring the level of oxidation i
6、n the oil.1.3 Acquisition of FT-IR spectral data for measuring oxidation in in-service oil and lubricant samples is described in PracticeD7418. In this test method, measurement and data interpretation parameters for oxidation using both direct trend analysis anddifferential (spectral subtraction) tr
7、end analysis are presented.1.4 This test method is based on trending of spectral changes associated with oxidation of in-service petroleum and hydrocarbonbased lubricants. Warnings or alarm limits can be set on the basis of a fixed minimum value for a single measurement or,alternatively, can be base
8、d on a rate of change of the response measured, see Ref (1).21.4.1 For direct trend analysis, values are recorded directly from absorption spectra and reported in units of absorbance per 0.1mm 0.1 mm pathlength.1.4.2 For differential trend analysis, values are recorded from the differential spectra
9、(spectrum obtained by subtraction of theabsorption spectrum of the reference oil from that of the in-service oil) and reported in units of 100*absorbance per 0.1 mm 0.1 mmpathlength (or equivalently absorbance units per centimetre).1.4.3 In either case, maintenance action limits should be determined
10、 through statistical analysis, history of the same or similarequipment, round robin tests, or other methods in conjunction with the correlation of oxidation changes to equipment performance.NOTE 1It is not the intent of this test method to establish or recommend normal, cautionary, warning, or alert
11、 limits for any machinery. Such limitsshould be established in conjunction with advice and guidance from the machinery manufacturer and maintenance group.1.5 This test method is for petroleum and hydrocarbon based lubricants and is not applicable for ester based oils, includingpolyol esters or phosp
12、hate esters.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6.1 ExceptionThe unit for wave numbers is cm-11.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is
13、 the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principl
14、es on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum P
15、roducts, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.96.03 on FTIR Testing Practices and Techniques Related to In-Service Lubricants.Current edition approved July 1, 2009Jan. 1, 2018. Published August 2009March 2018. Originally approved in 2009. Last previous edi
16、tion approved in 2009 asD7414 09. DOI: 10.1520/D7414-09.10.1520/D7414-18.2 The boldface numbers in parentheses refer to a list of references at the end of this standard.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes ha
17、ve been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official do
18、cument.*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 States12. Referenced Documents2.1 ASTM Standards:3D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liqu
19、ids (and Calculation of Dynamic Viscosity)D664 Test Method for Acid Number of Petroleum Products by Potentiometric TitrationD974 Test Method for Acid and Base Number by Color-Indicator TitrationD2896 Test Method for Base Number of Petroleum Products by Potentiometric Perchloric Acid TitrationD4739 T
20、est Method for Base Number Determination by Potentiometric Hydrochloric Acid TitrationD5185 Test Method for Multielement Determination of Used and Unused Lubricating Oils and Base Oils by InductivelyCoupled Plasma Atomic Emission Spectrometry (ICP-AES)D6304 Test Method for Determination of Water in
21、Petroleum Products, Lubricating Oils, and Additives by Coulometric KarlFischer TitrationD7412 Test Method for Condition Monitoring of PhosphateAntiwearAdditives in In-Service Petroleum and Hydrocarbon BasedLubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) SpectrometryD7415 Test M
22、ethod for Condition Monitoring of Sulfate By-Products in In-Service Petroleum and Hydrocarbon BasedLubricants by Trend Analysis Using Fourier Transform Infrared (FT-IR) SpectrometryD7418 Practice for Set-Up and Operation of Fourier Transform Infrared (FT-IR) Spectrometers for In-Service Oil Conditio
23、nMonitoringE131 Terminology Relating to Molecular SpectroscopyE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test MethodE2412 Practice for Condition Monitoring of In-Service Lubricants by
24、 TrendAnalysis Using Fourier Transform Infrared (FT-IR)Spectrometry3. Terminology3.1 DefinitionsFor definitions of terms relating to infrared spectroscopy used in this test method, refer to Terminology E131.For definitions of terms related to in-service oil condition monitoring, refer to Practice D7
25、418.3.2 machinery health, nqualitative expression of the operational status of a machine subcomponent, component, or entiremachine, used to communicate maintenance and operational recommendations or requirements in order to continue operation,schedule maintenance, or take immediate maintenance actio
26、n.4. Summary of Test Method4.1 This test method uses FT-IR spectrometry to monitor oxidation levels in in-service petroleum and hydrocarbon basedlubricants. The FT-IR spectra of in-service oil samples are collected according to the protocol for either direct trend analysis ordifferential trend analy
27、sis described in Practice D7418, and the levels of oxidation are measured using the peak height or areameasurements described herein.5. Significance and Use5.1 A large number of compounds, such as aldehydes, ketones, esters, and carboxylic acids, are produced when oils react withatmospheric oxygen.
28、Oxidation is measured using a common FT-IR spectral feature between 1800 and 1670 cm-11 caused by theabsorption of the carbonyl group present in most oxidation compounds. These oxidation products may lead to increased viscosity(causing oil thickening problems), acidity (causing acidic corrosion), an
29、d formation of sludge and varnish (leading to filterplugging, fouling of critical oil clearances and valve friction). Monitoring of oxidation products is therefore an important parameterin determining overall machinery health and should be considered in conjunction with data from other tests such as
30、 atomicemission (AE) and atomic absorption (AA) spectroscopy for wear metal analysis (Test Method D5185), physical property tests(Test Methods D445 and D6304), base reserve (Test Method D2896 and D4739), acid number tests (Test Methods D664 and D974)and other FT-IR oil analysis methods for nitration
31、 (Practice E2412), sulfate by-products (Test Method D7415), additive depletion(Test Method D7412), breakdown products and external contaminants (Practice E2412), which also assess elements of the oilscondition, see Refs (1-6).6. Interferences6.1 Various additive packages, especially those containing
32、 esters and carboxylic acids, such as some viscosity index improvers,pour point depressants, and rust inhibitors, can give false positives for oxidation. In addition, oils mixed with any synthetic esterbased oil products will also give very high values for oxidation. One should trend the in-service
33、oil against the new oil to helpidentify these interferences. In some oils the contributions from additive packages and synthetic ester based oils may be so highthat oxidation cannot be reliably measured.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Serv
34、ice at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.D7414 1826.2 High levels of water contamination and soot will also interfere with the measurement of oxidation.7. Apparatus7.1 Fourier transform infrared spec
35、trometer equipped with sample cell, filter (optional) and pumping system (optional) asspecified in Practice D7418.7.2 FT-IR Spectral Acquisition ParametersSet FT-IR spectral acquisition parameters according to instructions in PracticeD7418.8. Sampling8.1 Obtain a sample of the in-service oil and a s
36、ample of the reference oil (required only for differential trend analysis)according to the protocol described in Practice D7418.9. Preparation and Maintenance of Apparatus9.1 Rinse, flush, and clean the sample cell, inlet lines, and inlet filter according to instructions in Practice D7418.9.2 Monito
37、r cell pathlength as specified in Practice D7418.10. Procedure10.1 Collect a background spectrum according to the procedure specified in Practice D7418.10.2 Differential Trend Analysis OnlyCollect the absorption spectrum of a reference oil sample according to the procedurespecified in Practice D7418
38、.10.3 Collect the absorption spectrum of an in-service oil sample according to the procedure specified in Practice D7418.10.4 Data ProcessingAll data are normalized to a pathlength of 0.100 mm according to the procedure specified in PracticeD7418.11. Calculation11.1 Calculation of Oxidation Value:11
39、.1.1 Procedure A (Direct Trend Analysis)Oxidation by the direct trending method is calculated from the oil sample spectrumusing the measurement area and baseline points listed in Table 1. Fig. 1 illustrates the area used in the measurement of oxidationin the spectrum of diesel crankcase oil.11.1.2 P
40、rocedure B (Differential Trend Analysis)Oxidation by the differential trending method is calculated from thedifferential spectrum using the measurement peak and baseline points listed in Table 1. Fig. 2 illustrates the band used in themeasurement of oxidation in the differential spectrum of diesel c
41、rankcase oil.11.2 Sample CarryoverTo ensure the minimum amount of sample-to-sample cross-contamination or carryover, either aminimum volume of the subsequent sample or a solvent rinse should be used to flush out the previous sample. The efficacy of theflushing protocol may be assessed by consecutive
42、ly analyzing an oil having a low (or zero) oxidation level (L1, for example, afresh oil) and a used oil sample having a high oxidation level (H1) followed by a second run of the oil sample having a lowoxidation level (L2) and then calculating the percent carryover (PC) as follows. The calculated PC
43、should be less than 5%.5 %.PC5L22L1!/H1#3100 (1)where:L1, H1, and L2 = the values measured for oxidation (using the parameters given in Table 1) for the samples run in the indicatedsequence.12. Report12.1 Procedure A (Direct Trend Analysis)Values are reported in units of absorbance/0.100 mm.12.2 Pro
44、cedure B (Differential Trend Analysis)Values are reported in units of absorbance per centimeter (Abs/cm), calculatedas follows:TABLE 1 Parameters for Measuring Oxidation in In-ServicePetroleum and Hydrocarbon Based LubricantsMethod Measurement, cm Baseline Point(s), cm-1Procedure A(Direct Trend Anal
45、ysis)Area from1800 to 1670Minima 2200 to 1900and 650 to 550Procedure B(Differential Trend Analysis)Maximum height from1800 to 1660Single point at 1950D7414 183Oxidation in Abs/cm (2)5Oxidation in Abs/0.100 mm*10012.3 TrendingData shall be recorded and reported at selected time intervals during the l
46、ubricants life. Ideally, oxidationvalues would be compared to that of the newly formulated oil and plotted over time to visualize the relative changes in oxidationand to determine when there needs to be an oil change, albeit other parameters may dictate this change earlier. Sampling andreporting tim
47、e intervals for oxidation are based on the type of machinery and its previous history associated with this parameter.12.4 Statistical Analysis and Alarm LimitsFor statistical analysis and setting alarm limits, refer to Practice E2412, Annex A3on “Distribution Profiles and Statistical Analysis.”FIG.
48、1 Oxidation Measurement in the Spectrum of a Diesel Crankcase Oil for Direct Trend Analysis (Procedure A)FIG. 2 Oxidation Measurement in the Differential Spectrum of a Petroleum Crankcase Lubricant for Differential Trend Analysis (Proce-dure B)D7414 18412.5 Effects of Oil FormulationThe compositions
49、 of various oil formulations can have an effect on the results reported foroxidation value, and values from two different oil formulations should not be compared. Results should be interpreted relative tovalues measured for unused oils of the same formulation or trended directly from the sample history.13. Precision and Bias (Interim)413.1 PrecisionThe precision of the test method has not yet been determined by a formal interlaboratory study. Preliminaryexaminations of repeatability have shown that the difference between repetitive results obtained by the
