1、Designation: D7412 09D7412 18Standard 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 D7412; the numbe
2、r 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.1. Scope S
3、cope*1.1 This test method covers monitoring phosphate antiwear additives in in-service petroleum and hydrocarbon based lubricantssuch as various types of engine oils, hydraulic oils, and other lubricants that are formulated for protection against wear. Typicalphosphate antiwear additives include zin
4、c dialkyldithiophosphates, trialkyl phosphates, and triaryl phosphates.1.2 This test method uses Fourier Transform Infrared (FT-IR) spectrometry for monitoring of phosphate antiwear additivedepletion in in-service petroleum and hydrocarbon based lubricants as a result of normal machinery operation.
5、Monitoring thedepletion of phosphate antiwear additives in in-service lubricants can indicate unusual wear or severe operating conditions of themachine. This test method is designed as a fast, simple spectroscopic check for monitoring of phosphate antiwear additives inin-service petroleum and hydroc
6、arbon based lubricants with the objective of helping diagnose the operational condition of themachine based on measuring the level of phosphate antiwear additives in the oil.1.3 Acquisition of FT-IR spectral data for measuring phosphate antiwear additives in in-service oil and lubricant samples isde
7、scribed in Practice D7418. In this test method, measurement and data interpretation parameters for phosphate antiwear additivesusing both direct trend analysis and differential (spectral subtraction) trend analysis are presented.1.4 This test method is based on trending of spectral changes associate
8、d with phosphate antiwear additives in in-servicepetroleum and hydrocarbon based lubricants.Warnings or alarm limits can be set on the basis of a fixed minimum value for a singlemeasurement or, alternatively, can be based on a rate of change of the response measured, see Ref (1).21.4.1 For direct tr
9、end analysis, values are recorded directly from absorption spectra and reported in units of absorbance per 0.1mm pathlength.1.4.2 For differential trend analysis, values are recorded from the differential spectra (spectrum obtained by subtraction of theabsorption spectrum of the reference oil from t
10、hat of the in-service oil) and reported in units of 100*absorbance per 0.1 mm 0.1 mmpathlength (or equivalently absorbance units per centimeter).1.4.3 In either case, maintenance action limits should be determined through statistical analysis, history of the same or similarequipment, round robin tes
11、ts or other methods in conjunction with the correlation of changes in the level of phosphate antiwearadditives to equipment performance.NOTE 1It is not the intent of this test method to establish or recommend normal, cautionary, warning, or alert limits for any machinery. Such limitsshould be establ
12、ished 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 phosphate esters.1.6 The values stated in SI units are to b
13、e regarded as standard. No other units of measurement are included in this standard.1.6.1 ExceptionThe unit for wave numbers is cm-1.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to esta
14、blish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of S
15、ubcommitteeD02.96.03 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 edition approved in 2009 asD7412 09. DOI: 10.1520/D7412-09.10.1520/D7412-18.2
16、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 have been made to the previous version. Becauseit may not be technically poss
17、ible 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 document.*A Summary of Changes section appears at the end of this standardCop
18、yright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States11.8 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of Int
19、ernational Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)D2896 Test Me
20、thod for Base Number of Petroleum Products by Potentiometric Perchloric 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 TitrationD7414 Test Method for Condition Monitoring of Oxidation in In-Service Petroleum and Hydrocarbon Based Lubricants byTrend Analysis Using Fourier Transform Infrared (FT-IR) SpectrometryD7415 Test Method for Conditi
22、on 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 ConditionMonitoringE131 T
23、erminology 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 TrendAnalysis Us
24、ing 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 definition of terms related to in-service oil condition monitoring, refer to Practice D7418.3.2 machinery
25、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 action.4. Summary of Te
26、st Method4.1 This test method uses FT-IR spectrometry to monitor levels of phosphate antiwear additives in in-service petroleum andhydrocarbon based lubricants. The FT-IR spectra of in-service oil samples are collected according to the protocol for either directtrend analysis or differential trend a
27、nalysis described in Practice D7418, and the levels of phosphate antiwear additives aremeasured using the peak height or area measurements described herein.5. Significance and Use5.1 Antiwear additives are commonly used in petroleum and hydrocarbon based lubricants to prevent machinery wear byformin
28、g a chemical barrier activated by frictional heat. Antiwear additives that are phosphate based can be measured by FT-IRspectroscopy using the phosphate absorption band. Initially, phosphate antiwear additives will decompose and form a protectivefilm by binding to metal surfaces and through oxidative
29、 mechanisms, and so a decrease in the level of phosphate antiwear additiverelative to that in the new oil is expected during normal machinery operation. Subsequently, significant depletion of phosphateantiwear additives due to oxidation or hydrolysis can occur when the lubricant is subjected to high
30、 temperatures and high levelsof moisture. This usually occurs prior to the point where the oxidation of the lubricant begins to acceleratemaking accelerate,making trending of phosphate antiwear additives a useful indicator of the lubricants remaining in-service life. Monitoring ofphosphate antiwear
31、additive depletion is therefore an important parameter in determining overall machinery health and should beconsidered in conjunction with data from other tests such as atomic emission (AE) and atomic absorption (AA) spectroscopy forwear metal analysis (Test Method D5185), physical property tests (T
32、est Methods D445, D2896, and D6304) and other FT-IR oilanalysis methods for oxidation (Test Method D7414), sulfate by-products (Test Method D7415), nitration, breakdown products andexternal contaminants (Practice E2412), which also assess elements of the oils condition, see Refs (1-6).6. Interferenc
33、es6.1 High levels of glycol and ester based additives, or contaminants, or both, can interfere with the measurement of phosphateantiwear additives.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standard
34、svolume information, refer to the standards Document Summary page on the ASTM website.D7412 1827. Apparatus7.1 Fourier transform infrared spectrometer equipped with sample cell, filter (optional) and pumping system (optional) asspecified in Practice D7418.7.2 FT-IR Spectral Acquisition ParametersSet
35、 FT-IR spectral acquisition parameters according to instructions in PracticeD7418.8. Sampling8.1 Obtain a sample of the in-service oil and a sample of the reference oil (required only for differential trend analysis)according to the protocol described in Practice D7418.9. Preparation and Maintenance
36、 of Apparatus9.1 Rinse, flush, and clean the sample cell, lines, and inlet filter according to instructions in Practice D7418.9.2 Monitor cell pathlength as specified in Practice D7418.10. Procedure10.1 Collect a background spectrum according to the procedure specified in Practice D7418.10.2 Differe
37、ntial Trend Analysis OnlyCollect the absorption spectrum of a reference oil sample according to the procedurespecified in Practice D7418.10.3 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
38、 to a pathlength of 0.100 mm according to the procedure specified in PracticeD7418.11. Calculation11.1 Calculation of Phosphate Antiwear Value:11.1.1 Procedure A (Direct Trend Analysis)Phosphate antiwear value by the direct trending method is calculated from the oilsample spectrum using the measurem
39、ent area and baseline points listed in Table 1. Fig. 1 illustrates the area used in themeasurement of phosphate antiwear additives in the spectrum of diesel crankcase oil.11.1.2 Procedure B (Differential Trend Analysis)Phosphate antiwear value by the differential trending method is calculatedfrom th
40、e differential spectrum using a minimum peak height and a two-point baseline (Table 1), giving negative values as theamount of phosphate antiwear additives in the in-service oil relative to that in the reference oil progressively decreases. Fig. 2illustrates the band used in the measurement of phosp
41、hate antiwear additives in the differential spectrum of diesel crankcase 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 is used to flush out the previous sample. The effica
42、cy of the flushingprotocol may be assessed by consecutively analyzing a used oil sample having a low phosphate antiwear level (L1) and an oilhaving a high phosphate antiwear level (H1) followed by a second run of the oil sample having a low phosphate antiwear level(L2) and then calculating the perce
43、nt carryover (PC) as follows. The calculated PC should be 5%.5 %.PC5L22L1!/H1#3100 (1)where:L1, H1, and L2 = the values measured for phosphate antiwear additives (using the parameters given in Table 1) for the samplesrun in the indicated sequence.12. Report12.1 Procedure A (Direct Trend Analysis)Val
44、ues are reported in units of absorbance/0.100 mm.12.2 Procedure B (Differential Trend Analysis)Values are reported in units of absorbance per centimeter (Abs/cm), calculatedas follows:TABLE 1 Parameters for Measuring Phosphate AntiwearAdditives in In-Service Petroleum and Hydrocarbon BasedLubricants
45、Method Measurement, cm-1 Baseline 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 930D7412 183FIG. 1 Phosphate Antiwear Measurement in the Spectrum of a Di
46、esel Crankcase Oil for Direct Trend Analysis (Procedure A)FIG. 2 Phosphate Antiwear Measurement in the Differential Spectrum of a Petroleum Crankcase Lubricant for Differential Trend Analy-sis (Procedure B)D7412 184Phosphate Antiwear in Abs/cm (2)5Phosphate Antiwear in Abs/0.100 mm*10012.3 TrendingD
47、ata shall be recorded and reported at selected time intervals during the lubricants life. Ideally, phosphateantiwear values would be compared to that of the newly formulated oil and plotted over time to visualize the relative changes inphosphate antiwear additives and to determine when there needs t
48、o be an oil change, albeit other parameters may dictate thischange earlier. Sampling and reporting time intervals for phosphate antiwear additives are based on the type of machinery and itsprevious history associated with this parameter.12.4 Statistical Analysis and Alarm LimitsFor statistical analy
49、sis and setting alarm limits, refer to Practice E2412, Annex A3on “Distribution Profiles and Statistical Analysis.”12.5 Effects of Oil FormulationThe compositions of various oil formulations can have an effect on the results reported for thephosphate antiwear value, and values from two different oil formulations should not be compared. Results should be interpretedrelative to values 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 ha