1、Designation: D 7412 09Standard Test Method forCondition Monitoring of Phosphate Antiwear Additives inIn-Service Petroleum and Hydrocarbon Based Lubricants byTrend Analysis Using Fourier Transform Infrared (FT-IR)Spectrometry1This standard is issued under the fixed designation D 7412; the number imme
2、diately 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.1. Scope1.1 This
3、 test method covers monitoring phosphate antiwearadditives in in-service petroleum and hydrocarbon based lubri-cants such as various types of engine oils, hydraulic oils, andother lubricants that are formulated for protection against wear.Typical phosphate antiwear additives include zinc dialkyl-dit
4、hiophosphates, trialkyl phosphates and triaryl phosphates.1.2 This test method uses Fourier Transform Infrared (FT-IR) spectrometry for monitoring of phosphate antiwear addi-tive depletion in in-service petroleum and hydrocarbon basedlubricants as a result of normal machinery operation. Monitor-ing
5、the depletion of phosphate antiwear additives in in-servicelubricants can indicate unusual wear or severe operatingconditions of the machine. This test method is designed as afast, simple spectroscopic check for monitoring of phosphateantiwear additives in in-service petroleum and hydrocarbonbased l
6、ubricants with the objective of helping diagnose theoperational condition of the machine based on measuring thelevel of phosphate antiwear additives in the oil.1.3 Acquisition of FT-IR spectral data for measuring phos-phate antiwear additives in in-service oil and lubricant samplesis described in Pr
7、actice D 7418. In this test method, measure-ment and data interpretation parameters for phosphate antiwearadditives using both direct trend analysis and differential(spectral subtraction) trend analysis are presented.1.4 This test method is based on trending of spectralchanges associated with phosph
8、ate antiwear additives in in-service petroleum and hydrocarbon based lubricants. Warningsor alarm limits can be set on the basis of a fixed minimumvalue for a single measurement or, alternatively, can be basedon a rate of change of the response measured, see Ref (1).21.4.1 For direct trend analysis,
9、 values are recorded directlyfrom absorption spectra and reported in units of absorbance per0.1 mm pathlength.1.4.2 For differential trend analysis, values are recordedfrom the differential spectra (spectrum obtained by subtractionof the absorption spectrum of the reference oil from that of thein-se
10、rvice oil) and reported in units of 100*absorbance per 0.1mm pathlength (or equivalently absorbance units per centime-ter).1.4.3 In either case, maintenance action limits should bedetermined through statistical analysis, history of the same orsimilar equipment, round robin tests or other methods inc
11、onjunction with the correlation of changes in the level ofphosphate antiwear additives to equipment performance.NOTE 1It is not the intent of this test method to establish orrecommend normal, cautionary, warning or alert limits for any machinery.Such limits should be established in conjunction with
12、advice and guidancefrom the machinery manufacturer and maintenance group.1.5 This test method is for petroleum and hydrocarbonbased lubricants and is not applicable for ester based oils,including polyol esters or phosphate esters.1.6 The values stated in SI units are to be regarded asstandard. No ot
13、her units of measurement are included in thisstandard.1.6.1 ExceptionThe unit for wave numbers is cm-1.1.7 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 h
14、ealth practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D 2896 Test Method for Base Number of Petroleum Prod-uc
15、ts by Potentiometric Perchloric Acid Titration1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.96 on In-Service Lubricant Testing and Condition Monitoring Services.Current edition approved July 1
16、, 2009. Published August 2009.2The boldface numbers in parentheses refer to a 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, r
17、efer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D 5185 Test Method for Determination of Additive Ele-ments, Wear Metals, and Contaminants in Used Lubricat-ing Oils and De
18、termination of Selected Elements in BaseOils by Inductively Coupled Plasma Atomic EmissionSpectrometry (ICP-AES)D 6304 Test Method for Determination of Water in Petro-leum Products, Lubricating Oils, and Additives by Coulo-metric Karl Fischer TitrationD 7414 Test Method for Condition Monitoring of O
19、xidationin In-Service Petroleum and Hydrocarbon Based Lubri-cants by Trend Analysis Using Fourier Transform Infrared(FT-IR) SpectrometryD 7415 Test Method for Condition Monitoring of SulfateBy-Products in In-Service Petroleum and HydrocarbonBased Lubricants by Trend Analysis Using Fourier Trans-form
20、 Infrared (FT-IR) SpectrometryD 7418 Practice for Set-Up and Operation of Fourier Trans-form Infrared (FT-IR) Spectrometers for In-Service OilCondition MonitoringE 131 Terminology Relating to Molecular SpectroscopyE 2412 Practice for Condition Monitoring of Used Lubri-cants by Trend Analysis Using F
21、ourier Transform Infrared(FT-IR) Spectrometry3. Terminology3.1 DefinitionsFor definitions of terms relating to infraredspectroscopy used in this test method, refer to TerminologyE 131. For definition of terms related to in-service oil conditionmonitoring, refer to Practice D 7418.3.2 machinery healt
22、h, nqualitative expression of the op-erational status of a machine subcomponent, component, orentire machine, used to communicate maintenance and opera-tional recommendations or requirements in order to continueoperation, schedule maintenance, or take immediate mainte-nance action.4. Summary of Test
23、 Method4.1 This test method uses FT-IR spectrometry to monitorlevels of phosphate antiwear additives in in-service petroleumand hydrocarbon based lubricants. The FT-IR spectra ofin-service oil samples are collected according to the protocolfor either direct trend analysis or differential trend analy
24、sisdescribed in Practice D 7418, and the levels of phosphateantiwear additives are measured using the peak height or areameasurements described herein.5. Significance and Use5.1 Antiwear additives are commonly used in petroleum andhydrocarbon based lubricants to prevent machinery wear byforming a ch
25、emical barrier activated by frictional heat. Anti-wear additives that are phosphate based can be measured byFT-IR spectroscopy using the phosphate absorption band.Initially, phosphate antiwear additives will decompose andform a protective film by binding to metal surfaces and throughoxidative mechan
26、isms, and so a decrease in the level ofphosphate antiwear additive relative to that in the new oil isexpected during normal machinery operation. Subsequently,significant depletion of phosphate antiwear additives due tooxidation or hydrolysis can occur when the lubricant issubjected to high temperatu
27、res and high levels of moisture.This usually occurs prior to the point where the oxidation of thelubricant begins to acceleratemaking trending of phosphateantiwear additives a useful indicator of the lubricants remain-ing in-service life. Monitoring of phosphate antiwear additivedepletion is therefo
28、re an important parameter in determiningoverall machinery health and should be considered in conjunc-tion with data from other tests such as atomic emission (AE)and atomic absorption (AA) spectroscopy for wear metalanalysis (Test Method D 5185), physical property tests (TestMethods D 445, D 2896, an
29、d D 6304) and other FT-IR oilanalysis methods for oxidation (Test Method D 7414), sulfateby-products (Test Method D 7415), nitration, breakdown prod-ucts and external contaminants (Practice E 2412), which alsoassess elements of the oils condition, see Refs (1-6).6. Interferences6.1 High levels of gl
30、ycol and ester based additives, orcontaminants, or both, can interfere with the measurement ofphosphate antiwear additives.7. Apparatus7.1 Fourier transform infrared spectrometer equipped withsample cell, filter (optional) and pumping system (optional) asspecified in Practice D 7418.7.2 FT-IR Spectr
31、al Acquisition ParametersSet FT-IRspectral acquisition parameters according to instructions inPractice D 7418.8. Sampling8.1 Obtain a sample of the in-service oil and a sample of thereference oil (required only for differential trend analysis)according to the protocol described in Practice D 7418.9.
32、 Preparation and Maintenance of Apparatus9.1 Rinse, flush, and clean the sample cell, lines and inletfilter according to instructions in Practice D 7418.9.2 Monitor cell pathlength as specified in Practice D 7418.10. Procedure10.1 Collect a background spectrum according to the pro-cedure specified i
33、n Practice D 7418.10.2 Differential Trend Analysis OnlyCollect the absorp-tion spectrum of a reference oil sample according to theprocedure specified in Practice D 7418.10.3 Collect the absorption spectrum of an in-service oilsample according to the procedure specified in PracticeD 7418.10.4 Data Pr
34、ocessingAll data are normalized to a path-length of 0.100 mm according to the procedure specified inPractice D 7418.11. Calculation11.1 Calculation of Phosphate Antiwear Value:11.1.1 Procedure A (Direct Trend Analysis)Phosphateantiwear value by the direct trending method is calculated fromthe oil sa
35、mple spectrum using the measurement area andbaseline points listed in Table 1. Fig. 1 illustrates the area usedD7412092in the measurement of phosphate antiwear additives in thespectrum of diesel crankcase oil.11.1.2 Procedure B (Differential Trend Analysis)Phosphate antiwear value by the differentia
36、l trending method iscalculated from the differential spectrum using a minimumpeak height and a two-point baseline (Table 1), giving negativevalues as the amount of phosphate antiwear additives in thein-service oil relative to that in the reference oil progressivelydecreases. Fig. 2 illustrates the b
37、and used in the measurementof phosphate antiwear additives in the differential spectrum ofdiesel crankcase oil.11.2 Sample CarryoverTo ensure the minimum amount ofsample-to-sample cross-contamination or carryover, either aminimum volume of the subsequent sample or a solvent rinseis used to flush out
38、 the previous sample. The efficacy of theflushing protocol may be assessed by consecutively analyzinga used oil sample having a low phosphate antiwear level (L1)and an oil having a high phosphate antiwear level (H1)followed by a second run of the oil sample having a lowphosphate antiwear level (L2)
39、and then calculating the percentcarryover (PC) as follows. The calculated PC should be 5%.PC 5 L2L1!/H1 3 100 (1)where:L1, H1, and L2 = the values measured for phosphate anti-wear additives (using the parametersgiven in Table 1) for the samples run inthe indicated sequence.12. Report12.1 Procedure A
40、 (Direct Trend Analysis)Values are re-ported in units of absorbance/0.100 mm.12.2 Procedure B (Differential Trend Analysis)Values arereported in units of absorbance per centimeter (Abs/cm),calculated as follows:Phosphate Antiwear in Abs/cm5 Phosphate Antiwear in Abs/0.100 mm * 100 (2)12.3 TrendingDa
41、ta shall be recorded and reported atselected time intervals during the lubricants life. Ideally,phosphate antiwear values would be compared to that of thenewly formulated oil and plotted over time to visualize therelative changes in phosphate antiwear additives and to deter-mine when there needs to
42、be an oil change, albeit otherparameters may dictate this change earlier. Sampling andreporting time intervals for phosphate antiwear additives arebased on the type of machinery and its previous historyassociated with this parameter.12.4 Statistical Analysis and Alarm LimitsFor statisticalanalysis a
43、nd setting alarm limits, refer to Practice E 2412,Annex A3 on “Distribution Profiles and Statistical Analysis.”12.5 Effects of Oil FormulationThe compositions of vari-ous oil formulations can have an effect on the results reportedfor the phosphate antiwear value, and values from two differentoil for
44、mulations should not be compared. Results should beinterpreted relative to values measured for unused oils of thesame formulation or trended directly from the sample history.13. Precision and Bias (Interim)413.1 PrecisionThe precision of the test method has notyet been determined by a formal interla
45、boratory study. Prelimi-nary examinations of repeatability have shown that the differ-ence between repetitive results obtained by the same operatorin a given laboratory applying the same test method with thesame apparatus under constant operating conditions on identi-cal test material within short i
46、ntervals of time would in the longrun, in the normal and correct operation of the test method,exceed the following values only in one case in 20:repeatability = 0.53 absorbance units/0.100 mm forProcedure A (direct trend analysis)repeatability = 0.57 absorbance units/cm forProcedure B (differential
47、trend analysis)The reproducibility of this test method is being determinedand will be available on or before May 1, 2013.13.2 BiasThe procedures in this test method have no biasbecause the phosphate antiwear values can be defined only inthe terms of the test method and no accepted reference methodor
48、 value is available.14. Keywords14.1 condition monitoring; differential trend analysis; directtrend analysis; Fourier transform infrared; FT-IR; hydrocarbonbased lubricants; in-service petroleum lubricants; infrared; IR;lubricants; oils; phosphate antiwear4Supporting data have been filed at ASTM Int
49、ernational Headquarters and maybe obtained by requesting Research Report RR: D02-1667.TABLE 1 Parameters for Measuring Phosphate AntiwearAdditives in In-Service Petroleum and Hydrocarbon BasedLubricantsMethod Measurement, cm-1Baseline Point(s), cm-1Procedure A(Direct Trend Analysis)Area from1025 to 960Minima 2200 to 1900and 650 to 550Procedure B(Differential Trend Analysis)Minimum height from1020 to 930Two points at1020 and 930D7412093FIG. 1 Phosphate Antiwear Measurement in the Spectrum of a Diesel Crankcase Oil for Direct Trend Analysis (Procedure A)FIG. 2 P
