1、Designation: D8120 17Standard Test Method forFerrous Debris Quantification1This standard is issued under the fixed designation D8120; 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 parenthese
2、s indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes a means for quantitativedetermination of the concentration of ferrous debris in lubri-cants and greases.1.2 This test method pro
3、vides a determination of the con-centration of ferrous debris in the lubricant or grease from anominal 0 mg/kg to 10 000 mg/kg (1 % by mass) or greater.1.3 This test method is applicable to all types of lubricatingfluids (API Group I-V) and greases sampled from machineryand other mechanical equipmen
4、t, including reciprocating en-gine oils, turbine oils, hydraulic oils, gear oils, and bearinggreases.1.4 This test method describes a means by which a sampleof lubricant or grease is placed in a magnetometer apparatus,which determines the concentration of ferrous debris andprovides these readings di
5、rectly to the operator without furthercalculation.1.5 This test method is applicable to in-service lubricantsand greases at any stage of degradation.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not
6、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.1.8 This international standard was develo
7、ped 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 Docum
8、ents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD5185 Test Method for Multielement Determination ofUsed and Unused Lubricating Oils and Base Oils byInductively Coupled Plasma Atomic E
9、mission Spectrom-etry (ICP-AES)D5854 Practice for Mixing and Handling of Liquid Samplesof Petroleum and Petroleum ProductsD6595 Test Method for Determination of Wear Metals andContaminants in Used Lubricating Oils or Used HydraulicFluids by Rotating Disc Electrode Atomic Emission Spec-trometryD7669
10、Guide for Practical Lubricant Condition Data TrendAnalysisD7690 Practice for Microscopic Characterization of Par-ticles from In-Service Lubricants by Analytical Ferrogra-phyD7718 Practice for Obtaining In-Service Samples of Lubri-cating GreaseD7720 Guide for Statistically Evaluating Measurand AlarmL
11、imits when Using Oil Analysis to Monitor Equipmentand Oil for Fitness and ContaminationD7874 Guide for Applying Failure Mode and Effect Analy-sis (FMEA) to In-Service Lubricant Testing3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 ferrous debris concentration, nthe concentrat
12、ion,expressed as milligrams per kilogram or percentage (percent bymass) of ferrous debris in a sample of lubricant across allparticle size ranges of the debris, from dissolved to largeferrous debris particles in the millimeter size range. Note thatsuch ferrous debris may exist in a matrix in the lub
13、ricant suchas when organically combined or as part of a steel alloy.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.96.06 on Practices and Techniques for Prediction and Determi-na
14、tion of Microscopic Wear and Wear-related Properties.Current edition approved June 1, 2017. Published July 2017. DOI: 10.1520/D8120-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
15、ormation, refer to the standards Document Summary page onthe ASTM website.Copyright 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 standardiza
16、tion 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.13.1.2 sample, na portion of in-service oil or grease drawndirectly from the machinery without f
17、urther processing.4. Summary of Test Method4.1 A sample of in-service lubricant or grease is taken fromthe machinery or equipment and transferred into a suitablemeasurement receptacle. The manufacturers recommendationsshould be followed for preferred holders or receptacles buttypical container forma
18、ts include sample bottles, syringes, andgrease samplers. The sample holder is then manually placedinside an indicated empty measurement chamber of a magne-tometer apparatus. Some instruments may require the sampleholder to be removed before the measurement is complete andwill prompt accordingly. By
19、measuring the difference in signalbetween the filled chamber and the empty chamber, theconcentration of ferrous debris in milligrams per kilogram orpercent by mass is determined.5. Significance and Use5.1 By quantifying the concentration of total ferrous debris,this test method provides a direct ind
20、ication of wear in themachinery by enabling the user to pinpoint when there is adeviation from the normal buildup of ferrous debris shed by themachinery or when the concentration of ferrous debris hasexceeded safe operating limits. Specific guidance regardingsuch procedures may be found in Guides D7
21、669, D7720, andD7874.5.2 This test method can be performed on-site and can beutilized as a particle-size insensitive, minimum sample prepa-ration alternative to laboratory-based screening for abnormalmachinery conditions due to the presence of wear debris bymeans of ferrography as described in Pract
22、ice D7690,orelemental analysis methods such as atomic emissionspectrometry, described in Test Methods D5185 and D6595.6. Interferences6.1 This test method provides a measure of the concentra-tion of ferrous debris by measuring the magnetic susceptibilityof the sample under test. Non-ferrous debris,
23、which is ferro-magnetic (such as nickel or cobalt), may be reported as ferrousdebris using this test method.7. Apparatus7.1 The core apparatus consists of a solenoid-style magne-tometer with an inner coil diameter of sufficient size toaccommodate the sample holder. Standard in-service oil analy-sis
24、sample bottles (2 oz capacity), syringes (3 mL capacity),and grease pots (5 mL capacity) serve as sample holders. Othersample holders can be accommodated by sleeve adaptors madeof non-magnetic materials. The user should consult the manu-facturers literature for guidance in the selection and use ofsu
25、itable containers for the proposed sampling volumes. Anexciting AC magnetic field, with typical frequencies in therange of a few kHz to several tens of kHz and with a peakamplitude in the 0.001 T region, is applied to the lubricantunder test. The induced current in either a separate sensing coil,or
26、the excitation coil itself, due to the presence of the ferrousdebris is measured. From this induced current, the magneticsusceptibility of the lubricant is determined. This magneticsusceptibility is then correlated to the concentration of ferrousdebris in the lubricant by means of the known magnetic
27、susceptibility of such debris.8. Reagents and Materials8.1 A disposable, plastic sample container of sufficientcapacity to perform the measurement. Consult the instrumentmanufacturers instructions for the recommended containersand method of sample presentation.8.2 At least two calibration standards
28、of uniformly sus-pended ferrous material that provide equivalent magneticsusceptibilities within the lower and upper quartiles of theselected measurement range. These standards may consistentof, for example, suspended M50 bearing steel in oil or a resinmatrix and are to be used as check standards fo
29、r the purposesof confidence testing. An optional third standard for themid-range point is useful but not essential. Again, consult themanufacturers instructions for recommended practices regard-ing (re)calibration and check intervals.8.3 A lint-free, oil-absorbent material should be used toclean the
30、 apparatus. Some suitable examples would be poly-propylene industrial wipes or clean cotton shop rag.9. Hazards9.1 All precautions in the sampling and handling of in-service lubricant samples should be followed as appropriate.Please see Practices D4057, D4177,orD7718 for guidance onthis point.10. Sa
31、mpling, Test Specimens, and Test Units10.1 A sample of the liquid or grease should be obtainedfollowing the guidelines described in Practices D4057, D4177,or D7718. A representative portion of the lubricant and ofsufficient volume to fill the measurement bottle, syringe, and soforth should be collec
32、ted in a clean, dry container. Care shouldbe taken to ensure that the portion collected is as representativeof the in-service fluid or grease as possible. Avoid samplingfrom the bottom of sumps or other similar dead spots, wheredeposits may have built up over time. Consult the relevantASTM practices
33、 noted above for more guidance on suitablesampling points.Also, check that the sample is at a temperaturecompatible with the specifications of the sample containerbefore being drawn for analysis.10.2 Inspect the collected portion for homogeneity and if indoubt, have it re-homogenized to ensure that
34、a representativesample can be measured in the magnetometer. Follow PracticeD5854 and ensure that the collected portion is gently invertedback and forth for at least 30 s before drawing or decanting thesample into the measurement syringe or vial before proceed-ing.11. Preparation of Apparatus11.1 Tur
35、n on the apparatus and ensure that no alerts, whichmay indicate faults with the measurement hardware orsoftware, are generated.D8120 17211.2 Follow the manufacturers instructions for the opera-tion of the instrument.12. Calibration and Standardization12.1 Ferrous debris magnetometers are factory-cal
36、ibratedand standardized to report concentrations in milligrams perkilogram or percent by mass in oil or grease. The calibration islinear across the specified calibration range for most typicalapplications. Deviations from linear behavior can occur if thesample contains large debris particles. The po
37、int at which thisbecomes significant depends on the magnetic field strength, theexcitation frequency and the susceptibility of the debris par-ticles. However for typical iron and steels this is of the order ofa millimeter or so in diameter, at which point the debris isprobably visible to the naked e
38、ye.12.2 Note that the induced current caused by the debris isactually related to the mass of ferrous material present withinthe magnetic field. Wear debris magnetometers are designed sothat the sensing volume is essentially defined by the coilconstruction for a given sample vial format. This sensing
39、volume is independent of the overall volume of sample withinthe vial, and will be constant for any particular sample vialformat. Therefore, providing that the sample volume within thevial exceeds that of the sensing volume, the induced currentbecomes directly related to the concentration of ferrous
40、debriswithin the sample. During factory calibration, the responsedetermined can be related to the known concentration offerrous debris within the sample for a particular vial format.This procedure will be repeated for each style of sample vialthat the instrument can accommodate. Before performing am
41、easurement, it is important to choose the correct operationalmode, if the magnetometer accepts different sample vialformats, in order to achieve consistent results.12.3 If it is felt necessary to check the calibration of theapparatus, the manufacturers supplied check standards shouldbe used to perfo
42、rm confidence tests. The operator shouldfollow the procedure detailed in the instructions and comparethe results relative to the specified values indicated on therespective calibration standards. If these comparisons are outof specification, the measurements should be repeated. If anyare still out o
43、f range, report the results to the manufacturer forfurther instructions.13. Conditioning13.1 The apparatus should be sited away from any signifi-cant sources of magnetic interference (for example,transformers, power supplies, and so forth). Also, it is advis-able to avoid standing the instrument on
44、steel workbenches orsimilar.13.2 The apparatus should be switched on and allowed towarm up for at least 15 min.13.3 Consult the manufacturers instructions for any furtherconditioning steps.14. Procedure14.1 Ensure that both the sample chamber and the samplevial are visibly clean of oil or grease. Re
45、move any excess usingthe supplied cleaning materials.14.2 If appropriate, verify that the apparatus is set to theexpected measurement range of the lubricant under test. If theexpected range is unknown, it may be prudent to start at a lowrange and repeat at successively higher ranges until a stablean
46、d creditable result is obtained.14.3 Transfer the lubricant from the sampling bottle, usingclean, disposable syringes or similar, to the preferred measure-ment container. Consult the manufacturers instructions for theminimum quantity recommended for the type of measurementcontainer to be used. Wipe
47、off any spillage from the outside ofthe measurement container using the supplied cleaning mate-rial.14.4 Initiate the measurement cycle by the appropriatemeans for the particular apparatus as described in the manu-facturers instructions.14.5 Holding the sample vertically, insert the container inthe
48、measurement aperture when prompted.14.6 After a short delay, remove the sample container whenindicated by the apparatus.14.7 After a further short period, the measured concentra-tion will be displayed on the apparatus.15. Calculation or Interpretation of Results15.1 Upon completion of the procedure,
49、 the concentrationof ferrous debris is automatically calculated by the apparatus.15.2 If upon completion of the procedure, the concentrationof ferrous debris falls outside the measurement range set on theapparatus, the operator may be alerted of that fact and may beprompted to perform the procedure again using an appropriaterange.15.3 If an error code is displayed by the apparatus uponcompletion of the procedure, follow the manufacturers in-structions on next steps. For example, if the sample was notinserted correctly, a warning will be displayed, no ferrousreading will be
