1、Designation: D7667 10 (Reapproved 2015)Standard Test Method forDetermination of Corrosiveness to Silver by AutomotiveSpark-Ignition Engine FuelThin Silver Strip Method1This standard is issued under the fixed designation D7667; the number immediately following the designation indicates the year ofori
2、ginal 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 test method covers the determination of the corro-sivenes
3、s to silver by automotive spark-ignition engine fuel (forexample, gasoline), as defined by Specification D4814 orsimilar specifications in other jurisdictions, having a vaporpressure no greater than 124 kPa (18 psi) at 37.8 C (100 F)by one of two procedures.1.1.1 Procedure AInvolves the use of a pre
4、ssure vessel.1.1.2 Procedure BInvolves the use of a vented test tube.1.2 The values stated in SI units are to be regarded as thestandard. The values in parentheses are for information only.1.3 WARNINGMercury has been designated by manyregulatory agencies as a hazardous material that can causecentral
5、 nervous system, kidney and liver damage. Mercury, orits vapor, may be hazardous to health and corrosive tomaterials. Caution should be taken when handling mercury andmercury containing products. See the applicable product Ma-terial Safety Data Sheet (MSDS) for details and EPAswebsitehttp:/www.epa.g
6、ov/mercury/faq.htmfor addi-tional information. Users should be aware that selling mercuryand/or mercury containing products into your state or countrymay be prohibited by law.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibi
7、lity 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:2D130 Test Method for Corrosiveness to Copper from Petro-leum Products by Copper Strip TestD3241 T
8、est Method for Thermal Oxidation Stability ofAviation Turbine FuelsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4814 Specification for Automotive Spark-Ignition EngineFuelE1 Specification for ASTM Liquid
9、-in-Glass Thermometers2.2 Energy Institute Standards:3IP 227 Determination of Corrosiveness to Silver of AviationTurbine Fuels - Silver Strip Method2.3 ASTM Adjuncts:4Color standard for tube deposit rating (5 aluminum strips)3. Terminology3.1 Abbreviations:PTFE = polytetrafluoroethylenePV = pressure
10、 vesselPVP = pressure vessel procedureSSCD = silver strip centering deviceTSMD = temperature sensing and monitoring deviceVTTP = vented test tube procedure4. Summary of Test Method4.1 A polished, thin silver strip is immersed in 30 mL of thesample being tested, and heated at 50 C (122 F) for 2 h. At
11、the end of the heating period, the silver strip is removed,washed, and the color and tarnish level assessed against theSilver Strip Classifications in Table 1.5. Significance and Use5.1 Crude petroleum contains sulfur compounds, most ofwhich are removed during refining. However, of the sulfurcompoun
12、ds remaining in the petroleum product or introducedinto the fuel during storage and distribution, some can have a1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.05.0C on Color and
13、 Reactivity.Current edition approved Oct. 1, 2015. Published December 2015. Originallyapproved in 2010. Last previous edition approved in 2010 as D7667 102. DOI:10.1520/D7667-10R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.or
14、g. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K., http:/www.energyinst.org.uk.4Available from ASTM International Headquarters. Order Adjunct No.ADJD3241
15、. Original adjunct produced in 1986.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1corroding action on various metals and this corrosivity is notnecessarily related directly to the total sulfur content. Theeffect can vary according t
16、o the chemical types of sulfurcompounds present. The silver strip corrosion test is designedto assess the relative degree of corrosivity of a petroleumproduct towards silver and silver alloys.5.2 Under some circumstances, reactive sulfur compoundspresent in automotive spark-ignition engine fuels can
17、 tarnish oreven corrode silver alloy fuel gauge in-tank sender units orsilver-plated bearings (in 2-stroke cycle engines). To minimizeor prevent the failure of silver alloy in-tank sender units bytarnish or corrosion, Specification D4814 requires that fuelsshall pass a silver strip corrosion test.6.
18、 Apparatus6.1 Silver Strip Corrosion Pressure Vessel (Procedure A),constructed from stainless steel according to dimensions givenin Fig. 1, as described in Test Method D130. The vessel shallbe capable of withstanding a test pressure of 700 kPa (100 psi).Alternative designs for the vessels cap and sy
19、nthetic rubbergasket may be used provided that the internal dimensions of thevessel are the same as shown in Fig. 1, which allow a nominal25 mm by 150 mm (1 in. by 6 in.) test tube (see 6.2) and theSSCD (see 6.4) to be placed inside the pressure vessel.6.2 Test Tubes, of borosilicate glass of nomina
20、l 25 mm by150 mm (1 in. by 6 in.) dimensions, preferably graduated at30 mL volume.5,6The internal dimensions shall be checked asacceptable by use of a silver strip (see 7.4). When 30 mL ofsample is added to the test tube with the silver strip in it, aminimum of 5 mm of liquid shall be above the top
21、surface ofthe strip.6.3 Test Bath, General, whether liquid or solid, the test bathshall be able to maintain the test temperature to within 61C(2 F) of the required test temperature. It is recommended thatbaths be placed inside a fume-hood.6.3.1 Bath, shall be fitted with suitable supports to hold ea
22、chtest tube (see 6.2) in a vertical position to a depth of about100 mm (4 in.) as measured from the bottom of the test tube tothe bath surface.6.3.2 Bath Medium, as a liquid bath medium, both water andoil have been found to be satisfactory and controllable at thespecified test temperature and durati
23、on required by the testprocedure.6.3.3 Solid Block Bath, made of aluminum, shall meet thetest temperature control, test duration, and immersion condi-tions required by the test procedure, and shall be verified, atleast annually, for temperature measurement (heat transfer) byrunning tests on tubes fi
24、lled with 30 mL of product plus a thinsilver strip of the given nominal dimensions, plus a tempera-ture sensor.6.3.3.1 Wells provided in the solid block bath to accommo-date pressure vessels (see Fig. 1) shall be of the followingdimensions: 54 mm (218 in.) diameter from top, up to a depthof 70 mm (2
25、34 in.) continuing with an opening of 38 mm(112 in.) diameter up to a depth of 140 mm (512 in.). Anopening of 8 mm (516 in.) diameter by 210 mm (814 in.)depth shall be provided in the center of the block for immersionof a metal temperature sensor (connected to a suitable 50 C 61C (122 F 6 2 F) tempe
26、rature controller), or thermometer(see 6.5).6.3.3.2 Wells provided in the solid block bath to accommo-date test tubes shall be of the following dimensions: 20 mm(1116 in.) diameter by 140 mm (512 in.) deep. An opening of8 mm (516 in.) diameter by 210 mm (814 in.) depth shall beprovided in the center
27、 of the block for immersion of a metaltemperature sensor (connected to a suitable 50 C 6 1C(122 F 6 2 F) temperature controller), or thermometer (see6.5).6.3.3.3 Provide insulation made of 25.4 mm (1.0 in.) thickfiberglass with aluminum backing (or, similar insulation) tocover all the four sides of
28、the solid block bath.6.4 Silver Strip Centering Device (SSCD),7,6made of mate-rial which is gasoline-compatible at 50 C (122 F) for theduration of the test, such as Acetal Resin, White Nylon 6/6, orPTFE. See details in A1.1(Assembly View) and A1.2 (Indi-vidual Parts View). Length of SSCD inside the
29、test tube is suchthat the lower edge of the assembled silver strip is about22 mm (78 in.) from the bottom of the test tube.6.5 Temperature Sensing and Monitoring Device (TSMD),capable of sensing and monitoring the desired test temperaturein the bath to within an accuracy of 61 C (2 F). The ASTM5The
30、sole source of supply of the apparatus known to the committee at this timeis Quark Enterprises, Inc., 320 Morton Ave., Rosenhayn, NJ 08352.6If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation
31、at a meeting of the responsible technical committee,1which you may attend.7The sole source of supply of the apparatus known to the committee at this timeisK the test Procedure, A or B; test duration, minutes; andtest temperature, degrees Celsius, in the following format:Corrosion, silver strip, by D
32、7667, Procedure A or B, X at Y:Z (1)where:X = test duration, in minutes,Y = test temperature, C, andZ = classification category (that is 0, 1, 2, 3 or 4).14. Precision and Bias14.1 PrecisionThe precision of this test method has notbeen determined.NOTE 5In the case of results which consist of a ratin
33、g on a non-linearscale, no generally accepted method for determining precision or bias iscurrently available.14.2 BiasThe procedure in this test method has no biasbecause the results of silver corrosion are defined only in termsof this test method.15. Keywords15.1 automotive gasoline; corrosiveness
34、to silver; silvercorrosion; silver stripANNEX(Mandatory Information)A1. SILVER STRIP CENTERING DEVICE (SSCD)A1.1 Assembly ViewA1.1.1 See Fig. A1.1.A1.2 Individual Parts ViewA1.2.1 See Fig. A1.2.D7667 10 (2015)5NOTE 1MATERIAL: ALL PARTS - GASOLINE COMPATIBLE AT 50 C (122 F) for 2 H to 3 H/TEST SUCH A
35、S ACETAL RESIN, WHITENYLON 6/6 OR PTFE.FIG. A1.1 Assembly ViewD7667 10 (2015)6ASTM 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 determination of the valid
36、ity 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 comme
37、nts 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 committee, which you may attend. If you feel that your comments have n
38、ot received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple co
39、pies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 1MATERIAL: ALL PARTS - GASOLINE COMPATIBLE AT 50 C (122 F) for 2 H to 3 H TEST SUCH AS ACETAL RESIN, WHITENYLON 6/6 OR PTFE.All dimensions are in millimetres.FIG. A1.2 Individual Parts ViewD7667 10 (2015)7
