1、Designation: D6421 99a (Reapproved 2014)Standard Test Method forEvaluating Automotive Spark-Ignition Engine Fuel forElectronic Port Fuel Injector Fouling by Bench Procedure1This standard is issued under the fixed designation D6421; the number immediately following the designation indicates the year
2、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. Scope1.1 This test method covers a bench test procedure toevaluate
3、 the tendency of automotive spark-ignition engine fuelto foul electronic port fuel injectors (PFI). The test methodutilizes a bench apparatus equipped with Bosch injectorsspecified for use in a 1985-1987 Chrysler 2.2-L turbochargedengine.This test method is based on a test procedure developedby the
4、Coordinating Research Council (CRC) for prediction ofthe tendency of spark-ignition engine fuel to form deposits inthe small metering clearances of injectors in a port fuelinjection engine (see CRC Report No. 592).21.2 The test method is applicable to spark-ignition enginefuels, which may contain an
5、tioxidants, corrosion inhibitors,metal deactivators, dyes, deposit control additives,demulsifiers, or oxygenates, or a combination thereof.1.3 The values stated in SI units are to be regarded as thestandard. Approximate inch-pound units are shown in paren-theses for information purposes only.1.4 Thi
6、s standard does not 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. Specific precau-tiona
7、ry statements are given throughout this test method.NOTE 1If there is any doubt as to the latest edition of Test MethodD6421, contact ASTM International Headquarters. Other properties ofsignificance to spark-ignition engine fuel are described in SpecificationD4814.2. Referenced Documents2.1 ASTM Sta
8、ndards:3D4814 Specification for Automotive Spark-Ignition EngineFuelD5598 Test Method for Evaluating Unleaded AutomotiveSpark-Ignition Engine Fuel for Electronic Port Fuel Injec-tor Fouling2.2 ANSI Standard:4MC 96.1 American National Standard for Temperature Mea-surement Thermocouples2.3 CARB Standa
9、rd:5Test Method for Evaluating Port Fuel Injector (PFI) Depos-its in Vehicle Engines2.4 Clean Air Act Amendment:6Clean Air Act Amendments of 1990, Public Law 101549,Title 1 Provisions for Attainment and Maintenance ofNational Air Quality Standards3. Terminology3.1 Definitions of Terms Specific to Th
10、is Standard:3.1.1 base fuel, nunleaded automotive spark-ignition en-gine fuel that does not contain a deposit control additive butmay contain antioxidants, corrosion inhibitors, metaldeactivators, dyes, or oxygenates, or a combination thereof.3.1.2 cycle, na 15-s pulsing period, followed by a 50-min
11、heating period at 160C (320F), followed by a 10-mincool-down period.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.A0.01 on Gasoline and Gasoline-Oxygenate Blends.Current edition
12、 approved Oct. 1, 2014. Published November 2014. Originallyapproved in 1999. Last previous edition approved in 2009 as D642199a (2009).DOI: 10.1520/D6421-99AR14.2“A Program to Evaluate a Bench Scale Test Method to Determine the DepositForming Tendencies of Port Fuel Injectors,” available from Coordi
13、nating ResearchCouncil, Inc., 219 Perimeter Ctr. Pkwy., Atlanta, GA 30346.3For 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
14、ASTM website.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from California Air Resources Board, P.O. Box 2815, Sacramento,CA 95815. (Incorporated by reference in California Code of Regulations, Title 13,Secti
15、on 2257.)6Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.3 deposit
16、control additive, nmaterial added to the basefuel to prevent or remove deposits in the entire engine intakesystem.3.1.3.1 DiscussionFor the purposes of this test method,the performance of a deposit control additive is limited to theelectronic PFI tip areas.3.1.4 driveability, nthe quality of a vehic
17、les performancecharacteristics as perceived by the operator in response tochanges in throttle position.3.1.5 electronic port fuel injector (PFI), nan electrome-chanical device used to control fuel flow in an internalcombustion engine.3.1.6 fouling, vformation of carbonaceous deposits on thepintle or
18、 metering surfaces of an electronic fuel injector, whichreduces fuel flow rate.3.1.7 pintle, na needle-like metering device extendingbeyond the electronic fuel injector body that is part of anelectronic fuel injector, which controls flow rate and spraypattern.3.1.8 test fuel, nbase fuel, with or wit
19、hout the addition ofa deposit control additive, that is used for evaluation asdescribed in this test method.4. Summary of Test Method4.1 This test method describes a procedure for evaluatingthe formation of deposits in PFIs. The test method includes abench test procedure that has been shown to rapid
20、ly formdeposits in fuel injectors and a procedure for determiningresultant flow loss.4.2 This test method uses a simulated fuel system consistingof a fuel pump, filter, pressure regulator, fuel rail, and fuelinjectors. A heat source is applied to the fuel injectors tosimulate the hot-soak portion of
21、 the vehicle test (see TestMethod D5598).4.3 Each test begins with screened injectors that are knownto foul. The tips of these four clean fuel injectors are placed inan aluminum block. A stainless-steel internal reservoir is filledwith 2 L of the test fuel.4.4 During one 60-min test cycle, the fuel
22、injectors arepulsed for 15 s, followed by a 50-min hot-soak interval inwhich the injector aluminum block temperature controller is setat a temperature of 160C (320F) and the fuel pressure isregulated to 263 kPa (38 psig), followed by a 10-min cool-down period. Flow measurements for each of the injec
23、tors aretaken at the beginning of the test, after 22 cycles, and at the endof the test at 44 cycles.4.5 The change in the rate of flow for each injector from thestart to the end of the test is used to determine the foulingpercentage of each injector.5. Significance and Use5.1 Driveability problems i
24、n PFI automobiles were firstreported in 1984. Deposits are prone to form on the meteringsurfaces of pintle-type electronic fuel injectors. These depositsreduce fuel flow through the metering orifices. Reductions inmetered fuel flow result in an upset in the air-fuel ratio, whichcan affect emissions
25、and driveability. When heavy enough,these deposits can lead to driveability symptoms, such ashesitation, hard starting, or loss of power, or a combinationthereof, that are easily noticed by the average driver and thatlead to customer complaints. The mechanism of the formationof deposits is not compl
26、etely understood. It is believed to beinfluenced by many factors, including driving cycle, engineand injector design, and composition of the fuel.The procedurein this test method has been found to build deposits in PFIs ona consistent basis. This procedure can be used to evaluatedifferences in base
27、fuels and fuel additives. A study of PFIfouling was conducted in both the bench test and the vehicletest procedures to obtain a correlation. The vehicle tests wereconducted as described in Test Method D5598. The tests wereconducted on several base gasolines, with and without addi-tives blended into
28、these base fuels. The PFI bench test provedto be reliable, repeatable, and a good predictor of PFI foulingin test vehicles.5.1.1 State and Federal Legislative and RegulatoryActionLegislative and regulatory activity, primarily by thestate of California (see 2.3) and the federal government (see2.4), n
29、ecessitate the acceptance of a standard test method toevaluate the PFI deposit-forming tendency of an automotivespark-ignition engine fuel.5.1.2 Relevance of ResultsThe operating conditions anddesign of the laboratory apparatus used in this test method maynot be representative of a current vehicle f
30、uel system. Thesefactors must be considered when interpreting results.5.2 Test Validity:5.2.1 Procedural ComplianceThe test results are not con-sidered valid unless the test is completed in compliance with allrequirements of this test method. Deviations from the param-eter limits presented in Sectio
31、n 10 will result in an invalid test.Engineering judgment shall be applied during conduct of thetest method when assessing any anomalies to ensure validity ofthe test results.6. Apparatus6.1 Automatic Electronic PFI Bench Test Apparatus7,8This apparatus is composed of two units, a fuel handling unita
32、nd a controller.6.1.1 Fuel Handling UnitThis unit houses a machinedaluminum fuel rail and a heated aluminum block designed toaccommodate four PFIs. Heaters and thermocouples aremounted in the heated aluminum block. This unit also housesa 2.25-L stainless steel reservoir, an electric fuel pump, a fue
33、lregulator, and a variety of valves used to transfer fuel to andfrom the reservoir and to deliver fuel under pressure to theinjectors (see Annex A1).6.1.2 Programmable Microprocessor Controller or OtherControllerThe controller is used to fill the fuel reservoir,control and measure the temperature of
34、 the heated block, pulse7The following instrument has been found suitable by interlaboratory coopera-tive testing: Port Fuel Injector Bench Test Apparatus. Available from SouthwestResearch Institute, San Antonio, TX.8If you are aware of alternative suppliers, please provide this information toASTM I
35、nternational Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.D6421 99a (2014)2the injectors, control the soak period, count the number of testcycles, and control the flow period for the measuring of theflow rat
36、e. The unit is programmed to shut down automaticallyat the end of each 22-cycle period.6.1.3 External Pressure Regulator This regulator is usedto adjust the pressure of the nitrogen gas on the fuel system.This ensures that the pressure of the fuel in the fuel rail ismaintained with an accuracy of 66
37、.8 kPa (61.0 psi) during thetest.6.1.4 Electronic PFIsOnly Bosch EV1.1A (Part Number0280150360) pintle-style injectors shall be used.8,9The corre-sponding Chrysler Corp. part number is 4306024 and is clearlymarked on the injector. The protective cap shall be removedfrom the injector by cutting the p
38、lastic cap with a razor bladeand gently heating with a heat gun. The rubber o-rings andspacers shall be removed to expose the bare metal injector tip.Each injector shall be screened for fouling capability prior touse in the procedure. The screening procedure is found inAnnex A2.6.2 Testing AreaThe a
39、mbient atmosphere of the testingarea shall be reasonably free of contaminants. The temperatureshould be maintained at 24 6 5C (75 6 9F). Uniformtemperature is necessary to ensure repeatable injector flowmeasurements. The specific humidity shall be maintained at auniform comfortable level. (Warning P
40、rovide adequateventilation and fire protection in areas where flammable orvolatile liquids and solvents, or both, are used. Suitableprotective clothing is recommended.)6.3 Laboratory Equipment:6.3.1 Analytical BalanceAn analytical balance capable of0.01 g resolution with a maximum capacity of at lea
41、st 200 g isrecommended. The balance should be calibrated following themanufacturers procedure and frequency recommendations.6.3.2 Graduated CylindersFour graduated cylinders of 50or 100-mL capacity, accurate to the nearest millilitre arerecommended for use in flow testing.6.3.3 Low Voltage Power Sup
42、plyA 12 V, variable, directcurrent power source should be used in cleaning of theinjectors.6.3.4 Ultrasonic BathAn ultrasonic bath with heatingcapabilities should be used for the cleaning of the injectors.6.3.5 Pipette BulbA pipette bulb should be used to drawinjector cleaning solution into the inje
43、ctor for cleaning.6.3.6 PipetteA disposable transfer pipette should be usedto fill injectors with the cleaning solution during the cleaningprocedure.6.3.7 Plastic Disposable BeakersDisposable plastic bea-kers of approximately 150 mLor other containers of equivalentsize should be used to contain the
44、injector cleaning fluid duringthe clean up of the injectors.6.4 Data AcquisitionA data acquisition device, capable ofcollecting the raw data in accordance with 10.4, shall berequired.7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused for all test procedures. Unless o
45、therwise noted, it isintended that all reagents conform to the specifications of theCommittee on Analytical Reagents of the American ChemicalSociety, where such specifications are available.10Other gradesmay be used provided it is first ascertained that the reagent isof sufficient purity to permit i
46、ts use without lessening theaccuracy of the determinations.7.2 Berryman Chem-Dip Carburetor and Parts Cleaner8,11This cleaner has been found effective in removing thedeposits built up in the injectors. This cleaner or any othercarburetor or engine parts cleaner that is proven effective inremoving su
47、ch deposits shall be used to clean the injectors.(WarningBerryman Chem-Dip contains methylenechloride, monochlorotoluene, xylene, ethyl phenols, and xyle-nols that are extremely dangerous if inhaled, are skin irritant oncontact, and are carcinogenic.)7.3 Rinsing SolventA1:1 mixture of isooctane and
48、xylene,or suitable mixture of solvents, shall be used to rinse the benchtest apparatus reservoir, injectors, and fuel lines between tests.Approximately 1 L is used.7.4 Test FuelA test fuel is either a base fuel or ahomogeneous blend of additives and base fuel. A single batchshall be blended before t
49、he start of the test.Approximately 8 L(2 gal) of fuel is needed for a single test.7.5 Additive/Base FuelSome test requestors may requirethat the test fuel be blended at the test laboratory and, therefore,will supply the deposit control additive and may, at their optionor if a suitable base fuel is not available at the test laboratory,supply untreated base fuel. The test requestor shall supply thedeposit control additive and, if supplied, the base fuel inappropriate volumes and packaging to ensure safe and efficienthandling. Blending inst
