1、Designation: F 303 08Standard Practices forSampling for Particles in Aerospace Fluids andComponents1This standard is issued under the fixed designation F 303; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 These practices cover sampling procedures for use indetermining the particle cleanliness of liquids and liquidsamples from compone
3、nts. Three practices, A, B, and C, havebeen developed on the basis of component geometry in order toencompass the wide variety of configurations. These practicesestablish guidelines to be used in preparing detailed proceduresfor sampling specific components.NOTE 1The term cleanliness used in these p
4、ractices refers to solidparticles in the liquid. It does not generally cover other foreign matter suchas gases, liquids, and products of chemical degradation. Cleanliness withrespect to particulate contamination does not necessarily give any indica-tion of the other types of contamination.1.2 All co
5、mponents, regardless of application, may be testedprovided (1) the fluid medium selected is completely compat-ible with the materials, packing and fluid used in the testcomponent, and test apparatus, and (2) the fluid is handled inaccordance with the manufacturers recommendations andprecautions. A l
6、iquid shall be used as the test fluid medium.These test fluids may be flushing, rinsing, packing, end useoperating, or suitable substitutes for end use operating fluids.(WarningPractices for sampling surface cleanliness by thevacuum cleaner technique (used on clean room garments andlarge storage tan
7、ks) sampling gaseous fluids and handlinghazardous fluids such as oxidizers, acids, propellants, and soforth, are not within the scope of the practices presented;however, they may be included in addendums or separatepractices at a later date.Substitute fluids are recommended in place of end item flui
8、dsfor preassembly cleanliness determinations on componentsusing hazardous end item fluids. After obtaining the sample,the substitute fluid must be totally removed from the test partwith particular caution given to the possibility of trapped fluid.It is hazardous to use a substitute fluid for testing
9、 assembledparts where the fluid can be trapped in dead ends, behind seals,and so forth.)NOTE 2The word fluid used in these practices shall be assumed to bea liquid unless otherwise stated.1.3 The cleanliness of assemblies with or without movingparts may be determined at the time of test; however, mo
10、ve-ment of internal component parts during the test will createunknown quantities of contamination from wear. Practice Bcovers configurations requiring dynamic actuation to achieve asample. The practice does not differentiate between built-inparticles and wear particles.NOTE 3Defining allowable clea
11、nliness limits is not within the scopeof these practices.1.4 The three practices included are as follows:SectionsPractice AStatic Fluid Sampling (Method for extract-ing fluid from the test article for analysis. This ap-plies to components that have a cavity from whichfluid may be extracted)5-13Pract
12、ice BFlowing Fluid Sampling (Method for flush-ing contaminants from the test article for analysis.This applies to components which fluid can pass (1)directly through, or (2) pass into and out of by cy-cling)14-22Practice CRinse Fluid Sampling (Method for rinsingcontaminants from the test articles su
13、rfaces. Therinse fluid is analyzed for contamination. This ap-plies to components that do not have a fluid cavityor for other reasons are not adaptable to PracticesA and B)23-311.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsi
14、bility 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.2. Referenced Documents2.1 ASTM Standards:2D 1836 Specification for Commercial HexanesF311 Practice for ProcessingAerospace Liquid Samples
15、 forParticulate Contamination Analysis Using Membrane Fil-tersF 312 Test Methods for Microscopical Sizing and Counting1These practices are under the jurisdiction of ASTM Committee E21 on SpaceSimulation and Applications of Space Technology and are the direct responsibilityof Subcommittee E21.05 on C
16、ontamination.Current edition approved Nov. 1, 2008. Published December 2008. Originallyapproved in 1965 as D 242965 T. Redesignated F 303 in 1970. Last previousedition approved in 2002 as F 303 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service a
17、t serviceastm.org. For Annual Book of ASTMStandards volume information, refer 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.Particles from Aerospace Fluids on Membrane Filte
18、rsF 313 Test Method for Insoluble Contamination of Hydrau-lic Fluids by Gravimetric Analysis32.2 Military Standards:MIL-T-27602 Trichlorine Oxygen Propellant Compatibles4MIL-H-6083 Hydraulic Fluid Petroleum Base for Pressure4MIL-H-5606 Hydraulic Fluid Petroleum Base for AircarrierMissiles and Ordina
19、nce43. Terminology3.1 Definitions:3.1.1 analytical membranea membrane filter used to col-lect the contaminant particles for analysis.3.1.2 azeotropic mixturea solution of two or more liquids,the composition of which does not change upon distillation.Also known as azeotrope.3.1.3 blank analysissometi
20、mes referred to as “fluid tare,”“control level,” “reference contamination level,” or “back-ground level.” The blank analysis is the particulate contami-nation level of the test fluid when the test part is omitted.3.1.4 cleanup membranea membrane used to filter thecontaminant particles from the fluid
21、 medium.3.1.5 componentan individual piece or a complete assem-bly of individual pieces.3.1.6 field filter holdera throw-away or reusable cartridgecontaining an analytical membrane filter.3.1.7 initial cleanlinessthe measure of contamination re-moved from the test component at the time of test exclu
22、dingthat defined by operating cleanliness.3.1.8 membrane taresometimes referred to as “blankcount” or “control filter.” When applied to microscope meth-ods, the membrane tare is the quantity of particles determinedto be on the filter before the test fluid is filtered. When appliedto gravimetric meth
23、ods, the membrane tare is an amount ofweight increase imparted to the control filter when uncontami-nated test fluid is passed through.3.1.9 operating cleanlinessthe measure of contaminantsgenerated by moving parts in the component during a specifiedperiod of dynamic operation.3.1.10 solvent filteri
24、ng dispenseran apparatus to dispensea stream of 2.0 m or finer membrane filtered fluid.3.1.11 system tareThe measure of contamination deter-mined by replacing the test component with a connectingfitting and following the cleanliness test procedure as ifchecking the test component.4. Summary of Pract
25、ices4.1 Cleanliness is determined by sampling and analyzingfluid that has been in contact with the surface being analyzed.Specific methods are recommended; however, other methodshave been recognized due to the wide variety of componentsand different test equipment used by industry. Recommendedand al
26、ternative methods are given in Fig. 1, Fig. 2, and Fig. 3.PRACTICE ASTATIC FLUID SAMPLING5. Scope5.1 This practice covers procedures for determining theparticulate contamination level of fluids from components thathave a cavity from which fluid may be extracted.6. Summary of Practice6.1 Fluid is ext
27、racted from the component and analyzed todetermine the particulate contamination level. Recommendedand alternative methods are given in Fig. 1.6.2 It is recommended that all operations of this practice beconducted in a dust controlled area. Cleanliness level of thedust controlled area shall be consi
28、stent with the componentcontamination limits.7. Significance and Use7.1 Although a cleaning action is imparted to the testcomponent, it is not the intent of this practice to serve as acleaning procedure. Components are normally cleaner aftereach consecutive test; thus repeated tests may be used toes
29、tablish process limits for a given component (Fig. 4). Aspecific set of test parameters must be supplied by the agencyspecifying cleanliness limits. Fig. 1, Fig. 2, and Fig. 3 may beused as a guide to establish the desired parameters of test fluid,vibration, extraction, and analysis.7.2 The curve in
30、 Fig. 4 shows the typical behavior of acomponent when tested for cleanliness several consecutive3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19
31、111-5098, Attn: NPODS.FIG. 1 Recommended and Alternative Methods for Static FluidSampling (Practice A)F303082times. Stabilization generally occurs before the fifth successiverun. The stabilized region starts where a horizontal line throughthe maximum stabilized value intersects the curve.7.3 The all
32、owable cleanliness limit of a test componentshould be based on the cleanliness requirements of the systemin which it will be used and the assigned value should begreater than the maximum stabilized value. When defining theallowable cleanliness limits, an important consideration is thatthe accuracy o
33、f the results decreases as the allowable limitvalue approaches the stabilized value.8. Apparatus8.1 Apparatus, as described in Practice F 313.8.2 Apparatus, as described in Test Methods F 312 or asdescribed in Practice F311.8.3 Automatic Particle Counter, as required.8.4 Vibration Equipment, as spec
34、ified.8.5 Apparatus Setup for Removing Component FluidSample, as shown in Fig. 4.NOTE 4Any suitable syringe and solvent dispensing devices may beused.8.6 Apparatus Setup for Providing Filtered Fluids, as shownin Fig. 5 (Note 4).9. Reagents59.1 Purity of ReagentsReagent grade chemicals shall beused i
35、n all tests. Unless otherwise indicated, it is intended that5A Material Safety Data Sheet (MSDS) can be obtained from the vendor. Thefollowing website can also provide MSDSs for all materials: Note that the specific fluorocarbon must beidentified.FIG. 2 Recommended and Alternative Methods for Flow T
36、hroughSampling (Practice B)FIG. 3 Recommended and Alternative Methods for Rinse FluidSampling (Practice C)FIG. 4 Contamination per Test Run Versus Consecutive Test RunNumberF303083all reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Socie
37、ty,where such specifications are available.6Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.9.2 Reagents must be compatible with the materials, fluid,and seals used in the co
38、mponent and apparatus.9.3 All reagents shall be prefiltered through a 2-m or finerabsolute membrane filter prior to use unless this requirement isimpractical due to the fluid used or sizes monitored in whichcase the user must filter as necessary.9.4 Low surface tension reagents commonly used are asf
39、ollows:9.4.1 Petroleum Ether,9.4.2 Hexane, in accordance with Specification D 1836.9.4.3 Isopropyl Alcohol,9.4.4 Fluorocarbons,9.4.5 Mineral Spirits,9.4.6 Trichloroethylene, in accordance with MIL-T-27602,and9.4.7 Azeotropic mixture of ethyl acetate (47 % vol) andcyclohexane (53 % vol).9.4.8 Deioniz
40、ed water.NOTE 5Methyl-chloroform, used in these practices, is toxic, and isbeing phased out for many applications. Methyl-chloroform has beenreplaced in this edition of these practices. The replacement solvents wereselected based on tests and analyses performed by The AerospaceCorporation and descri
41、bed in SMC-TR-9528.7NOTE 6Trichloroethylene has been labeled a potential human car-cinogen by the Environmental ProtectionAgency. Use should be restrictedto limit human exposure.10. Preparation of Apparatus10.1 Installation Requirements for Fig. 6The followingrequirements must be accomplished prior
42、to and during assem-bly of the apparatus shown in Fig. 6.(WarningAll connec-tions must be finger tight only.)10.1.1 Install the double valve and fluid outlet plastic tube.10.1.2 Remove caps or plugs, or both, from the field filterholder and place them in a covered, precleaned, petri dish.10.1.3 Inst
43、all the field filter holder onto the double valve,taking care to place the inlet side of the field filter holdertowards the fluid being withdrawn.10.1.4 Install fluid inlet needle onto the monitor.(WarningThe fluid inlet needle must be precleaned prior toeach usage.)10.2 General Requirements for Fig
44、. 6:10.2.1 A control blank must be accomplished on the appa-ratus setup before fluid is withdrawn for component fluidsampling.10.2.2 It is recommended that the field filter holders be usedone time only for component fluid sampling. However, clean-ing in sufficient numbers might warrant their reuse,
45、provided itis first determined that the monitors are sufficiently cleaned topermit their reuse without lessening the accuracy of thedetermination.10.2.3 Always actuate the syringe plunger slowly whenfilling or ejecting fluid.10.2.4 For ease of actuation, the syringe plunger must belubricated. If the
46、 plunger is extremely hard to actuate, checkthe plunger seal for swelling which would indicate noncom-patibility with the fluids utilized.10.2.5 In order to minimize seal swell, it is desirable toremove the syringe plunger when not in use. Lubricate prior toeach reassembly.10.3 Installation Requirem
47、ents for Fig. 7The followingrequirements must be accomplished prior to and during assem-bly on the apparatus shown in Fig. 7.(WarningSee 10.1.)10.3.1 Eject all fluid from the syringe.10.3.2 Install the hypodermic adapter and fluid outlet needleonto the double valve. (WarningThe hypodermic adapterand
48、 fluid outlet needle must be precleaned and the hypodermicadapter filter disk replaced prior to each usage.)10.3.3 Exercise extreme caution to assemble the hypoder-mic adapter in the correct configuration. Tighten sufficiently toeffect a seal.10.4 General Requirements for Fig. 5:6Reagent Chemicals,
49、American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.7Aerospace Corporation Report No. TR95 (5448)-1, “Non-Volatile ResidueSolvent Replacement.”Available from TheAerospace Corporation, P.O. Box 92957,Los Angeles
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