1、Designation: G 122 96 (Reapproved 2008)Standard Test Method forEvaluating the Effectiveness of Cleaning Agents1This standard is issued under the fixed designation G 122; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONMany systems require a high degree of cleanliness. For example, gaseous and liquid oxygen systemsmust be clean, particu
3、larly of hydrocarbons, to avoid the potential hazard of a reaction and subsequentfire or explosion. Typically, chlorinated solvents have been used to clean systems and equipment thatmust be free of hydrocarbons and other contaminants. Environmental concerns dictate that suitablereplacements are need
4、ed. This test method presents a procedure that may be used to evaluate candidateaqueous or non aqueous cleaning agents.1. Scope1.1 This test method covers a procedure for evaluating thecapability of cleaning agents and processes to remove contami-nation to the desired level.1.2 The test coupons prov
5、ide a relatively rough surface towhich contamination can easily adhere.1.3 The capability of a particular cleaning agent dependsupon the method by which it is used and the characteristics ofthe article being cleaned, such as size, shape, and material.Final evaluation of the cleaning agent should inc
6、lude testing ofactual products and production process.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is therespon
7、sibility 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. Specific precau-tionary statements are given in Note 2.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent Wate
8、rE 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG94 Guide for Evaluating Metals for Oxygen ServiceG 121 Practice for Preparation of Contaminated Test Cou-pons for the Evaluatio
9、n of Cleaning Agents2.2 ANSI Standard:D46.1 Surface Texture (Surface Roughness, Waviness,Lay)33. Terminology3.1 Definitions:3.1.1 cleaning effectiveness factor (CEF), nthe fraction ofcontaminant removed from an initially contaminated testcoupon and determined by gravimetric techniques.3.1.2 residual
10、 contamination, Rc, nthe absolute mass ofcontaminant remaining after the cleaning process and ex-pressed in milligrams per square centimetre of area or option-ally as milligrams per square foot.3.1.3 surface roughness, RA, nthe arithmetic averagedeviation of the surface profile from the centerline,
11、normallyreported in micrometres.4. Summary of Test Method4.1 This test method provides quantitative results as to theability of a specific cleaning agent/process for removingselected contaminants from standard coupons. The couponsused for testing are prepared in accordance with PracticeG 121. Cleani
12、ng is performed using a cleaning tank with orwithout ultrasonic agitation, elavated temperature or othercleaning enhancement features and depends on the manufac-turers instructions. The effectiveness of the cleaning process isrepresented as CEF, the cleaning effectiveness factor, that is the1This te
13、st method is under the jurisdiction of ASTM Committee G04 onCompatibility and Sensitivity of Materials in Oxygen Enriched Atmospheres and isthe direct responsibility of Subcommittee G04.01 on Test Methods.Current edition approved Sept. 1, 2008. Published October 2008. Originallyapproved in 1993. Las
14、t previous edition approved in 2002 as G 122 93(2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Availa
15、ble from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.fraction of the contaminant removed as determined by gravi-metric
16、 techniques. A control coupon is used to account for anycorrosion or material removal effects due to the cleaningagent/process.5. Significance and Use5.1 The purpose of this test method is to define a procedurefor evaluating the capability of cleaning agents to cleanmetallic coupons. Based on the ou
17、tcome of the testing, suitablecleaning agents may be selected for cleaning in general and foroxygen service in particular.5.2 The cleaning parameters can be changed and the testmethod can be repeated. The usual cleaning parameters includecleaning agent concentration, temperature, and time; type ands
18、trength of ultrasonic energy or agitation, if used, and others.NOTE 1Usual cleaning parameters are based on the manufacturersrecommendations.6. Apparatus6.1 Materials:6.1.1 Test Coupon, prepared in accordance with PracticeG 121. The mass of the coupon is approximately 30 to 45 g butwill vary signifi
19、cantly for each selected material. Typicalmaterials used in oxygen systems are described in Guide G94.6.1.2 Control CouponThis is uncontaminated and is sub-jected to the identical cleaning procedure as the contaminatedcoupons and serves to evaluate corrosion, erosion of the testcoupons.6.1.3 Cleanin
20、g Agent, prepared according to the manufac-turers instructions. Specification D 1193 Type II water shall beused for preparing aqueous solutions.6.2 Equipment:6.2.1 Cleaning Tank, A vessel of sufficient size to conduct anumber of evaluations simultaneously. Testing is enhanced byhaving automatic temp
21、erature and time controls. A cleaningtank with ultrasonics may be used.6.2.2 Balance, accuracy to 0.1 mg. However, 0.01 mgaccuracy is desirable to detect contamination levels of 10mg/m2(1 mg/ft2) or less.6.2.3 Beaker HolderA device to support beakers in theultrasonic cleaner tank such that the beake
22、rs do not contact thebottom and sides of the tank.7. Test Procedure7.1 Prepare a minimum of six test coupons by PracticeG 121.7.2 Indicate the masses of coupons in grams as MXy whereX is the coupon designation (number, letter, or name) and y =1indicates a clean coupon, y = 2 indicates a contaminated
23、coupon and y = 3 indicates a coupon after cleaning.7.3 Designate one coupon as the control coupon to undergocleaning without contamination.7.4 Measure the mass of the control and test coupons(recording them as MX1 as previously defined).7.5 Contaminate five test coupons in accordance with Prac-tice
24、G 121.7.6 Measure the mass of all contaminated test coupons(recording them as MX2 as previously defined).7.7 Process the control coupon in the test cleaning solutionseparately from the contaminated test coupons.7.8 The contaminated test coupons can be processed inindependent beakers held in the clea
25、ning tank or as a batch ina single beaker.7.9 Clean the test and control coupons in the candidatecleaning agent by the manufacturers procedure or selectedprocedure.7.9.1 Prepare the cleaning agent in accordance with themanufacturers recommendations.7.9.2 Select beakers of suitable size to accommodat
26、e the testcoupons and fit the beaker holder.7.9.3 Wash the beakers thoroughly with a solution of liquid,surface-active cleaning agent in hot water and rinse with typeII water.7.9.4 Fill the beakers with the cleaning agent solution to alevel that will ensure the test coupons are submerged.7.9.5 Fill
27、the cleaning tank to its operating level with thetransfer fluid and preheat to desired test temperature.7.9.6 Place the beakers in the beaker holder in the tank sothat the liquid levels in the tank and beakers are approximatelyequal.7.9.7 Allow the temperatures of the tank fluid and cleaningagent in
28、 the beakers to equilibrate at the desired temperature.7.9.8 Suspend the test coupons and control coupon in thecleaning agent, using a wire hook of the same material as thecoupon or a compatible material. Position the coupons suchthat they do not touch the beaker or one another.7.9.9 Begin agitation
29、 or sonication in the cleaning processand start the timer.7.9.10 Upon completing the required cleaning time, discon-tinue the agitation or sonication, and remove the coupons fromthe cleaning agent.7.9.11 Rinse the test coupon in accordance with the manu-facturers recommendations.7.9.12 Allow the sus
30、pended coupons to dry overnight or ina forced convection oven for one hour.NOTE 2Warning: Do not place test coupons directly in the oven afterapplication of the solution containing the contaminant.Afire may result ifthe solvent is flammable or rapid evaporation of the solvent may causespattering of
31、the contaminant thereby reducing the amount of contaminanton the test coupon. It is recommended that the test coupons be air drieduntil no traces of a liquid phase are visible.7.9.13 Determine the final mass of each test coupon (record-ing them as MX3 as previously defined), including the controlcou
32、pon.8. Calculation8.1 Validation of ProcedureExamine the control couponsto determine whether they lost mass (such as might occur ifthere was corrosion occurring, if the coupons were dissolving,or if the standard cleaning procedure used prior to contamina-tion had left residue on the coupons); gained
33、 mass (such asmight occur if the solution was plating a material on theirsurfaces, or was depositing contaminant rather than removingit) or exhibited the same mass. The simplest valid testprocedure is one in which there is no change in the control-coupons mass to within the measurement error of the
34、balance.G 122 96 (2008)28.1.1 If the control coupon is designated MC, and, if |MC3MC1 | balance error, then the experiment is valid.Proceed to calculate a cleaning effectiveness factor.8.1.2 If | MC3MC1 | is greater than the balance error, thetest may be considered to be suspect and the reason for t
35、hemass change should be investigated.8.2 Cleaning Effectiveness Factor (CEF):8.2.1 The cleaning effectiveness factor indicates the frac-tional contaminant that was removed during cleaning (forexample, CEF = 0.9 indicates that 90 % of the contaminantwas removed). CEF 5MX2 2 MX3MX2 2 MX1(1)where:MX2 M
36、X3 = the mass of contaminant removed, andMX2 MX1 = the mass of contaminant applied.8.2.2 Calculate the CEF for each test coupon.8.2.3 Calculate the average CEF by arithmetic mean.8.3 Residual Contamination (RC):8.3.1 A cleaning agent does not necessarily remove a fixedfraction of the contamination o
37、n a given surface. In some cases,it cleans a surface to a constant residual cleanliness level. Forexample, sometimes the cleaned surface will exhibit a layer oforganic material that has remained after a fluid vehicle hasdried, and a constant RC for varying initial contaminationlevels suggests this m
38、ay be happening.8.3.2 Calculate the contaminated area (S) of each coupon insquare centimeters.8.3.3 Calculate the residual contamination that is(MX3MX1) in grams.8.3.4 Using the equation RC =(MX3MX1)/S, calculatethe value of RC for each coupon (milligrams/centimetre2).8.3.5 Determine an average RC i
39、n mg/cm2.8.3.6 As an option, RC can be calculated in mg/ft2.9. Report9.1 Because of the many variables involved in conducting acleaning test program, it is necessary that all data be carefullydocumented.9.2 Report the following information, as applicable:9.2.1 Date of test,9.2.2 Technician,9.2.3 Con
40、taminant identification, and9.2.4 Coupon Data Refer to Practice G 121:9.2.4.1 Identification number of each coupon,9.2.4.2 Material,9.2.4.3 Surface roughness, (RA) micrometres, and9.2.4.4 Coupon Contaminated surface areas.9.2.5 Cleaning Data:9.2.5.1 Cleaning agent identification,9.2.5.2 Concentratio
41、n of cleaning agent,9.2.5.3 pH of diluted cleaning agent,9.2.5.4 Ultrasonic, soak, or agitation,9.2.5.5 Time,9.2.5.6 Temperature,9.2.5.7 Level of ultrasonic frequency (kHz), and9.2.5.8 Power density in watts per litre.9.2.6 Rinsing Data:9.2.6.1 Agent,9.2.6.2 Time,9.2.6.3 Temperature,9.2.6.4 Number o
42、f rinses, and9.2.6.5 Agitation method (if any).9.2.7 Drying Data:9.2.7.1 Method,9.2.7.2 Time, and9.2.7.3 Temperature.9.2.8 Test Data:9.2.8.1 Initial mass of each coupon, including control cou-pon, MX1 and MC1,9.2.8.2 Mass of each coupon with contaminant, MX2,9.2.8.3 Mass of each cleaned coupon after
43、 cleaning, MX3,and9.2.8.4 Mass of control coupon after cleaning, MC3.9.2.8.5 Report | MC3MC1 | and give comparison tobalance error.9.2.8.6 Report (MX2MX3) and (MX2MX1) and CEFfor each test coupon.9.2.8.7 Report average CEF.9.2.8.8 Report area of contamination in square centimetres.9.2.8.9 Report (MX
44、3MX1) and RC in milligrams/squarecentimetre.9.2.8.10 Report average RC (mg/cm2).9.2.8.11 Report average RC in milligrams/foot2(optional).10. Precision and Bias10.1 An interlaboratory study of the cleaning effectivenessfactor (CEF) was conducted using the general test protocol ofPractice E 691 in six
45、 participating laboratories with threematerials. However, not every laboratory evaluated everymaterial.410.1.1 The terms repeatability limit and reproducibilitylimit in Table 1 are used as specified in Practice E 177.10.2 BiasSince there is no accepted reference materialsuitable for determining the
46、bias for the procedure for measur-ing the CEF in this test method, bias has not been determined.11. Keywords11.1 cleaning agents; cleaning evaluation; cleaning process;contaminant; oxygen; oxygen systems; reagent; solvent4Supporting data have been filed at ASTM International Headquarters and maybe o
47、btained by requesting Research Report RR: G041001.TABLE 1 CEFPrecisionAMaterialCEFAverageRepeat-abilityStandardDeviationRepro-ducibilityStandardDeviationRepeat-abilityLimitRepro-ducibilityLimitA 0.9866 0.0154 0.0197 0.0432 0.0552B 0.9531 0.0404 0.0507 0.1131 0.1420C 0.4074 0.1008 0.1146 0.2821 0.320
48、8AThe table was calculated using the relationship: Limit = 2.8 3 standarddeviation.G 122 96 (2008)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that deter
49、mination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical comm
