1、Designation: D6421 99a (Reapproved 2014)D6421 18Standard 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 t
2、he year 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. Scope Scope*1.1 This test method covers a bench test proce
3、dure to evaluate the tendency of automotive spark-ignition engine fuel to foulelectronic port fuel injectors (PFI). The test method utilizes a bench apparatus equipped with Bosch injectors specified for use ina 1985-1987 Chrysler 2.2-L2.2 Lturbocharged engine.This test method is based on a test proc
4、edure developed by the CoordinatingResearch Council (CRC) for prediction of the tendency of spark-ignition engine fuel to form deposits in the small meteringclearances of injectors in a port fuel injection engine (see CRC Report No. 592).21.2 The test method is applicable to spark-ignition engine fu
5、els, which may contain antioxidants, corrosion inhibitors, metaldeactivators, dyes, deposit control additives, demulsifiers, or oxygenates, or a combination thereof.1.3 The values stated in SI units are to be regarded as the standard. Approximate inch-pound units are shown in parenthesesfor informat
6、ion purposes only.standard. The values given in parentheses after SI units are provided for information only and arenot considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard
7、to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. Specific precautionary statements are given throughout this test method.NOTE 1If there is any doubt as to the latest edition of Test Method D6421,
8、contactASTM International Headquarters. Other properties of significanceto spark-ignition engine fuel are described in Specification D4814.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principle
9、s for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and LubricantsD4814 Specification
10、for Automotive Spark-Ignition Engine FuelD5500 Test Method for Vehicle Evaluation of Unleaded Automotive Spark-Ignition Engine Fuel for Intake Valve DepositFormationD5598 Test Method for Evaluating Unleaded Automotive Spark-Ignition Engine Fuel for Electronic Port Fuel Injector Fouling2.2 ANSI Stand
11、ard:4MC 96.1 American National Standard for Temperature Measurement Thermocouples2.3 CARB Standard:5Test Method for Evaluating Port Fuel Injector (PFI) Deposits in Vehicle Engines1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and
12、 is the direct responsibility of SubcommitteeD02.A0.01 on Gasoline and Gasoline-Oxygenate Blends.Current edition approved Oct. 1, 2014Dec. 1, 2018. Published November 2014December 2018. Originally approved in 1999. Last previous edition approved in 20092014as D6421D6421 99a (2014).99a (2009). DOI: 1
13、0.1520/D6421-99AR14.10.1520/D6421-18.2 “AProgram to Evaluate a Bench Scale Test Method to Determine the Deposit Forming Tendencies of Port Fuel Injectors,” available from Coordinating Research Council,Inc., 219 Perimeter Ctr. Pkwy., Atlanta, GA 30346.5755 North Point Parkway, Suite 265, Alpharetta,
14、GA 30022, http:/www.crcao.org.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from American Natio
15、nal Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.5 Available from California Air Resources Board, P.O. Box 2815, Sacramento, CA 95815. (Incorporated by reference in California Code of Regulations, Title 13, Section2257.)This document is not an ASTM st
16、andard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all ca
17、ses only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.4 Clean Air
18、Act Amendment:6CleanAirActAmendments of 1990, Public Law 101549, Title 1 Provisions forAttainment and Maintenance of NationalAirQuality Standards3. Terminology3.1 For general terminology, refer to Terminology D4175.6 Available from U.S. Government Printing Office Superintendent of Documents, 732 N.
19、Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.D6421 1823.2 Definitions:3.2.1 base fuel, nin automotive spark-ignition engine fuels, a material composed primarily of hydrocarbons that may alsocontain oxygenates, anti-oxidants, corrosion inhibitors, metal deactivators
20、, and dyes but does not contain deposit control or leadadditives. D55003.2.1.1 DiscussionA jurisdiction may set limits on lead content from all sources.3.2.2 driveability, nin vehicles equipped with internal combustion engines, the quality of a vehicles performancecharacteristics under a range of co
21、nditions as perceived by the operator. D48143.2.2.1 DiscussionThe performance characteristics may include cold starting and warm-up, acceleration, idling, and hot starting.3.3 Definitions of Terms Specific to This Standard:3.1.1 base fuel, nunleaded automotive spark-ignition engine fuel that does no
22、t contain a deposit control additive but maycontain antioxidants, corrosion inhibitors, metal deactivators, dyes, or oxygenates, or a combination thereof.3.3.1 cycle, na 15-s15 s pulsing period, followed by a 50-min50 min heating period at 160C (320F),160 C (320 F),followed by a 10-min10 min cool-do
23、wn period.3.3.2 deposit control additive, nmaterial added to the base fuel to prevent or remove deposits in the entire engine intakesystem.3.3.2.1 DiscussionFor the purposes of this test method, the performance of a deposit control additive is limited to the electronic PFI tip areas.3.1.4 driveabili
24、ty, nthe quality of a vehicles performance characteristics as perceived by the operator in response to changesin throttle position.3.3.3 electronic port fuel injector (PFI), nan electromechanical device used to control fuel flow in an internal combustionengine.3.3.4 fouling, vformation of carbonaceo
25、us deposits on the pintle or metering surfaces of an electronic fuel injector, whichreduces fuel flow rate.3.3.5 pintle, na needle-like metering device extending beyond the electronic fuel injector body that is part of an electronic fuelinjector, which controls flow rate and spray pattern.3.3.6 test
26、 fuel, nbase fuel, with or without the addition of a deposit control additive, that is used for evaluation as describedin this test method.4. Summary of Test Method4.1 This test method describes a procedure for evaluating the formation of deposits in PFIs. The test method includes a benchtest proced
27、ure that has been shown to rapidly form deposits in fuel injectors and a procedure for determining resultant flow loss.4.2 This test method uses a simulated fuel system consisting of a fuel pump, filter, pressure regulator, fuel rail, and fuel injectors.A heat source is applied to the fuel injectors
28、 to simulate the hot-soak portion of the vehicle test (see Test Method D5598).4.3 Each test begins with screened injectors that are known to foul. The tips of these four clean fuel injectors are placed in analuminum block. A stainless-steel internal reservoir is filled with 2 L 2 L of the test fuel.
29、4.4 During one 60-min60 min test cycle, the fuel injectors are pulsed for 15 s, 15 s, followed by a 50-min50 min hot-soakinterval in which the injector aluminum block temperature controller is set at a temperature of 160C (320F)160 C (320 F) andthe fuel pressure is regulated to 263 kPa (38 psig), kP
30、a (38 psig), followed by a 10-min10 min cool-down period. Flowmeasurements for each of the injectors are taken at the beginning of the test, after 22 cycles, and at the end of the test at 44 cycles.4.5 The change in the rate of flow for each injector from the start to the end of the test is used to
31、determine the foulingpercentage of each injector.5. Significance and Use5.1 Driveability problems in PFI automobiles were first reported in 1984. Deposits are prone to form on the metering surfacesof pintle-type electronic fuel injectors. These deposits reduce fuel flow through the metering orifices
32、. Reductions in metered fuelflow result in an upset in the air-fuel ratio, which can affect emissions and driveability. When heavy enough, these deposits canD6421 183lead to driveability symptoms, such as hesitation, hard starting, or loss of power, or a combination thereof, that are easily noticedb
33、y the average driver and that lead to customer complaints. The mechanism of the formation of deposits is not completelyunderstood. It is believed to be influenced by many factors, including driving cycle, engine and injector design, and compositionof the fuel. The procedure in this test method has b
34、een found to build deposits in PFIs on a consistent basis. This procedure canbe used to evaluate differences in base fuels and fuel additives. A study of PFI fouling was conducted in both the bench test andthe vehicle test procedures to obtain a correlation. The vehicle tests were conducted as descr
35、ibed in Test Method D5598. The testswere conducted on several base gasolines, with and without additives blended into these base fuels. The PFI bench test proved tobe reliable, repeatable, and a good predictor of PFI fouling in test vehicles.5.1.1 State and Federal Legislative and Regulatory ActionL
36、egislative and regulatory activity, primarily by the state ofCalifornia (see 2.3) and the federal government (see 2.4), necessitate the acceptance of a standard test method to evaluate the PFIdeposit-forming tendency of an automotive spark-ignition engine fuel.5.1.2 Relevance of ResultsThe operating
37、 conditions and design of the laboratory apparatus used in this test method may notbe representative of a current vehicle fuel system. These factors must be considered when interpreting results.5.2 Test Validity:5.2.1 Procedural ComplianceThe test results are not considered valid unless the test is
38、completed in compliance with allrequirements of this test method. Deviations from the parameter limits presented in Section 10 will result in an invalid test.Engineering judgment shall be applied during conduct of the test method when assessing any anomalies to ensure validity of thetest results.6.
39、Apparatus6.1 Automatic Electronic PFI Bench Test Apparatus7,8This apparatus is composed of two units, a fuel handling unit and acontroller.6.1.1 Fuel Handling UnitThis unit houses a machined aluminum fuel rail and a heated aluminum block designed toaccommodate four PFIs. Heaters and thermocouples ar
40、e mounted in the heated aluminum block. This unit also houses a2.25-L2.25 L stainless steel reservoir, an electric fuel pump, a fuel regulator, and a variety of valves used to transfer fuel to andfrom the reservoir and to deliver fuel under pressure to the injectors (see Annex A1).6.1.2 Programmable
41、 Microprocessor Controller or Other ControllerThe controller is used to fill the fuel reservoir, controland measure the temperature of the heated block, pulse the injectors, control the soak period, count the number of test cycles, andcontrol the flow period for the measuring of the flow rate. The u
42、nit is programmed to shut down automatically at the end of each22-cycle period.6.1.3 External Pressure Regulator RegulatorThis regulator is used to adjust the pressure of the nitrogen gas on the fuelsystem. This ensures that the pressure of the fuel in the fuel rail is maintained with an accuracy of
43、 66.8 kPa (61.0 psi) 66.8 kPa(61.0 psi) during the test.6.1.4 Electronic PFIsOnly Bosch EV1.1A(Part Number 0280150360) pintle-style injectors shall be used.8,9 The correspond-ing Chrysler Corp. part number is 4306024 and is clearly marked on the injector. The protective cap shall be removed from the
44、injector by cutting the plastic cap with a razor blade and gently heating with a heat gun. The rubber o-rings and spacers shall beremoved to expose the bare metal injector tip. Each injector shall be screened for fouling capability prior to use in the procedure.The screening procedure is found in An
45、nex A2.6.2 Testing AreaThe ambient atmosphere of the testing area shall be reasonably free of contaminants. The temperature shouldbe maintained at 2424 C65C (755 C (75 F69F).9 F). Uniform temperature is necessary to ensure repeatable injector flowmeasurements. The specific humidity shall be maintain
46、ed at a uniform comfortable level. (WarningWarningProvide Provideadequate ventilation and fire protection in areas where flammable or volatile liquids and solvents, or both, are used. Suitableprotective clothing is recommended.)6.3 Laboratory Equipment:6.3.1 Analytical BalanceAn analytical balance c
47、apable of 0.01 g 0.01 g resolution with a maximum capacity of at least 200g 200 g is recommended. The balance should be calibrated following the manufacturers procedure and frequency recommenda-tions.6.3.2 Graduated CylindersFour graduated cylinders of 5050 mL or 100-mL100 mL capacity, accurate to t
48、he nearest millilitreare recommended for use in flow testing.6.3.3 Low Voltage Power SupplyA12V, 12 V, variable, direct current power source should be used in cleaning of the injectors.6.3.4 Ultrasonic BathAn ultrasonic bath with heating capabilities should be used for the cleaning of the injectors.
49、6.3.5 Pipette BulbA pipette bulb should be used to draw injector cleaning solution into the injector for cleaning.7 The following instrument has been found suitable by interlaboratory cooperative testing: Port Fuel Injector Bench Test Apparatus. Available from Southwest ResearchInstitute, San Antonio, TX.8 If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1 which you
