1、Designation: D4858 13Standard Test Method forDetermination of the Tendency of Lubricants to PromotePreignition in Two-Stroke-Cycle Gasoline Engines1This standard is issued under the fixed designation D4858; the number immediately following the designation indicates the year oforiginal adoption or, i
2、n 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1
3、This test method2evaluates the performance of lubri-cants intended for use in two-stroke-cycle spark-ignition gaso-line engines that are prone to preignition.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard
4、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.2. Referenced Documents2.1 ASTM S
5、tandards:3B152/B152M Specification for Copper Sheet, Strip, Plate,and Rolled BarD439 Specification for Automotive Gasoline (Withdrawn1990)4D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids (and Calculation of Dynamic Viscos-ity)D664 Test Method for Acid Number of Petroleum Pr
6、oductsby Potentiometric TitrationD874 Test Method for Sulfated Ash from Lubricating Oilsand AdditivesD910 Specification for Aviation GasolinesD2270 Practice for Calculating Viscosity Index from Kine-matic Viscosity at 40 and 100CD2699 Test Method for Research Octane Number of Spark-Ignition Engine F
7、uelD2700 Test Method for Motor Octane Number of Spark-Ignition Engine FuelD2885 Test Method for Determination of Octane Number ofSpark-Ignition Engine Fuels by On-Line Direct Compari-son TechniqueD2896 Test Method for Base Number of Petroleum Productsby Potentiometric Perchloric Acid TitrationD4857
8、Test Method for Determination of the Ability ofLubricants to Minimize Ring Sticking and Piston Depositsin Two-Stroke-Cycle Gasoline Engines Other Than Out-boardsD4863 Test Method for Determination of Lubricity of Two-Stroke-Cycle Gasoline Engine LubricantsE230 Specification and Temperature-Electromo
9、tive Force(EMF) Tables for Standardized Thermocouples2.2 ANSI Standard:ANSI MC 96.1 American National Standard for Tempera-ture Measurement Thermocouples53. Terminology3.1 Definitions:3.1.1 combustion chamberin reciprocating internal com-bustion engines, the volume bounded by the piston crown andany
10、 portion of the cylinder walls extending above the pistoncrown when in the top dead center position, and the innersurface of the cylinder head including any spark plugs andother inserted components.3.1.2 preignitionin a spark-ignition engine, ignition of themixture of fuel and air in the combustion
11、chamber before thepassage of the spark.3.1.3 scuff, scuffngin lubrication , damage caused byinstantaneous localized welding between surfaces in relative1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of Subcommitt
12、eeD02.B0.06 on Two-Stroke Cycle Gasoline.Current edition approved June 15, 2013. Published July 2013. Originallyapproved in 1988. Last previous edition approved in 2008 as D4858 08. DOI:10.1520/D4858-13.2Until the next revision of this test method, the ASTM Test Monitoring Centerwill update changes
13、in this test method by means of Information Letters. These canbe obtained from theASTM Test Monitoring Center, 6555 PennAve., Pittsburgh, PA15206-4489. Attention: Administrator. This edition incorporates revisions in allInformation Letters through No. 013.3For referenced ASTM standards, visit the AS
14、TM 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.4The last approved version of this historical standard is referenced onwww.astm.org.5Available from Ameri
15、can National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.*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 States1motion that doe
16、s not result in immobilization of the parts.D48633.1.4 spark plug foulingdeposition of essentially noncon-ducting material onto the electrodes of a spark plug that may,but will not necessarily, prevent the plug from operating.D48573.1.5 spark plug whiskering, also spark plug bridgingadeposit of cond
17、uctive material on the spark plug electrodeswhich tends to form a bridge between them, thus shorting outthe plug. D48573.2 Definitions of Terms Specific to This Standard:3.2.1 major preignitionpreignition that causes a tempera-ture increase of 10C or more measured at the inner surface ofthe cylinder
18、 head.3.2.2 minor preignitionpreignition that causes a tempera-ture increase of more than 7C and less than 10C measured atthe inner surface of the cylinder head.4. Summary of Test Method4.1 The test is run in a 49 cm3single-cylinder air-cooledengine operated under the conditions required by the spec
19、ifi-cation against which it is being run. These are typically4000 rpm wide open throttle (WOT) using a 20:1 ratio ofgasoline-to-oil by volume for a minimum of 50 h. The numberof incidences of preignition, as indicated by a rapid increase incombustion chamber temperature, is recorded.NOTE 1Pass-Fail
20、CriterionThe number of occurrences of preigni-tion during the test of a candidate oil shall not exceed that permitted by thespecification against which it is run.5. Significance and Use5.1 Two-stroke-cycle gasoline engines are generally moreprone to preignition than are four-stroke-cycle engines due
21、 tothe absence of the internal cooling that takes place during theinduction stroke of the four-stroke-cycle engines. Preignitioncan lead to major piston damage, either directly due tolocalized overheating or as the result of preignition-induceddetonation. Some lubricant additives that are widely use
22、d infour-stroke-cycle gasoline engine oils are known to increasethe probability of preignition in gasoline two-stroke-cycleengines. This procedure is used to determine the tendency of anoil to induce preignition in both water-cooled and air-cooledtwo-stroke-cycle gasoline engines.6. Apparatus6.1 Tes
23、t Engine and Stand:6.1.1 Test Engine ConfigurationA Yamaha CE-50 49 cm3loop-scavenged air-cooled two-stroke-cycle engine is used.6This has 40 mm bore, 39.2 mm stroke, with an aluminumpiston operating in a cast iron cylinder bore. The cylinder headis removable, with a hemispherical combustion chamber
24、. Forthe purposes of this test, modify the head as specified in6.3.1.1. Further details are given in Annex A1.NOTE 2The engine designation normally includes a final letterindicating the model, such as CE-50S, the model on which this test wasdeveloped. If this model is not available check the suitabi
25、lity for this testof available models with the manufacturer.66.1.2 Test StandThe dynamometer shall be able to absorb2.5 kW at (4000 to 6000) rpm with an inherent torquemeasurement accuracy of 60.5 % or better, and be capable ofmaintaining (4000 6 30) rpm with varying power input. Adirect shaft drive
26、 or a belt drive from the engine crankshaftmay be used. A complete test stand assembly, as shown in Fig.1, is available.76.1.3 Cooling BlowerRemove the original internal enginefan or have its blades machined off. A variable delivery blowerwith a free flow capacity of about 34 m3/min of air isrecomme
27、nded. Direct the flow from the blower toward theintake side of the engine. A suitable arrangement is shown inFig. 1.6The sole source of supply of the apparatus known to the committee at this timeis Engineering and Service Dept., Yamaha Motor Corp., 6555 Katella Ave Cypress,CA 90630. Parts, but not c
28、omplete engines, may be obtained from Yamahamotorcycle dealers. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.7Orde
29、r from Southwest Research Institute, Automotive Products and EmissionsResearch Division, 6220 Culebra Rd., San Antonio, TX 782385166.FIG. 1 Test StandD4858 1326.1.4 Fuel SystemMaintain fuel delivery pressure at (19 to21) kPa. The temperature of the fuel entering the carburetorshall not exceed 25 C,
30、and this might require cooling in hotclimates.6.2 Instrumentation:6.2.1 TachometerAn electronic tachometer accurate to625 rpm.6.2.2 Measurement of Ambient Conditions6.2.2 is writtenon the assumption that the engine draws ambient air from thetest room. If it is supplied with air from a controlled sou
31、rce,references to ambient temperature, pressure and humidityapply to the air from the controlled source.6.2.2.1 TemperatureProvide a thermocouple or thermom-eter to read air temperature in the range (10 to 50) C.6.2.2.2 Barometric PressureA barometer recording thepressure in the test room is require
32、d.6.2.2.3 HumidityA hygrometer or a wet and dry bulbthermometer is also required.6.2.2.4 RecorderContinuous recording of the ambientconditions is recommended.6.2.3 Calibration Calibrate the tachometer, ambienttemperature, and pressure measurement devices every 90 days.The calibration standard shall
33、be traceable to NIST.6.3 Engine and System Temperatures:6.3.1 Combustion Chamber Temperature:6.3.1.1 Modification of Cylinder HeadFit the cylinderhead with a shielded thermocouple. A thermocouple of theiron-constantan type meeting the requirements of ANSI 91.6Type J (summarized very briefly in Speci
34、fication E230)isrecommended, but any thermocouple capable of performingsatisfactorily under the conditions of the test can be used.8Thegeneral dimensions and machining requirements are shown inFig. 2. The through hole, in which the thermocouple is requiredto fit closely, is about 3 mm diameter, and
35、the counterbore shallnot extend closer than 4 mm to the combustion chambersurface. The dimensions of the counterbore and thread are notcritical, being suitable to available thermocouples, but thethread diameter shall be less than 14 mm.A18 27-NPTF threadis recommended. Make the thermocouple so that
36、the last (3 to4) mm of its tip is a snug fit into the 3 mm diameter portion ofthe hole, and be mounted in the head so that its tip protrudessufficiently to allow it to be ground flush with the internalsurface of the head without penetrating the shield. When a headhas been newly fitted with a thermoc
37、ouple, run a break-in inaccordance with 10.2 and Table 1. The thermocouple readingnormally requires about 90 min to stabilize.6.3.1.2 Shutdown ProvisionMake provision for shutdownof the engine in the case of a rapid (1 min or less) combustionchamber temperature increase of 10 C or more. This normall
38、yindicates an incidence of major preignition, and is required tominimize the risk of damage to the engine. An automatic shutdown when such an increase is experienced is recommended.At the least, provide an alarm to operate after a temperatureincrease of (6 to 7) C to allow manual shut down by theope
39、rator if the 10 C limit is exceeded.6.3.2 Exhaust TemperatureA thermocouple is required inthe exhaust elbow within about 65 mm of the cylinder exhaustport to monitor exhaust temperature.7Locate the thermocouplejunction within 63 mm of the center of the pipe.6.3.3 Spark Plug Gasket Temperature The sp
40、ark pluggasket may be fitted with one or two thermocouples, thenumber depending on the instrumentation used. A design thathas been found satisfactory is described in Appendix X1.96.3.4 Combustion Chamber and Spark Plug Gasket Tem-perature RecordersRecord these temperatures using a systemcapable of s
41、toring the data for later retrieval. Maximuminterval between successive recordings of the combustionchamber temperature is 2 s. A system with a range from (40 to750) C and an overall accuracy of 62 C is suitable.6.3.5 Calibration Calibrate the combustion chamber, ex-haust and spark plug gasket tempe
42、rature measurement devicesevery 90 days. The calibration standard shall be traceable toNIST.6.4 Fuel System:6.4.1 Flow MeterAny type accurate to 60.01 kg/h atabout 1 kg/h flow rate can be used. Instruments measuringmass directly are preferred. If a volumetric measurement meteris used, determine the
43、temperature-density relationship overthe operating range for the actual fuel-non-reference oil mix-ture used. Employ that relationship in the volume-mass con-version.8A suitable instrument is available from Omega Engineering Inc., P.O. Box4047, One Omega Dr., Stanford, CT 069070047.9A thermocouple b
44、asket that has been found satisfactory may be obtained fromThe Lewis Engineering Company, 238 Water St., Naugatuck, CT 06770.FIG. 2 Machining of Cylinder HeadD4858 1336.4.2 A temperature measuring device reading to at least40 C to an accuracy of 61 C and a pressure gauge ortransducer reading up to a
45、bout 35 kPa to an accuracy of 62%are required to monitor the temperature and pressure of the fuelentering the carburetor.7. Materials and Reagents7.1 Test FuelThe test fuel is a leaded gasoline consistingessentially of hydrocarbons, except for conventional leadantiknock, anticorrosion, anti-icing, e
46、tc. additives in normalconcentration, and containing no non-lead metallic antiknockcompounds or oxygenated blending compounds such as alco-hols or ethers. It contains (0.4 to 0.6) g/L of lead as lead alkylswith conventional motor mix or aviation mix scavengers, andshall have a minimum motor octane n
47、umber of 83, a maximumsensitivity (research octane number minus motor number) of12 as determined by Test Methods D2699, D2700,orD2885,as applicable, and shall otherwise meet the requirements ofSpecification D439 volatility grade A or B. Aviation gasolinemeeting these requirements and otherwise confo
48、rming toSpecification D910 Grade 100 or 100LL may be used. Use fuelfrom the same batch for calibration running and for any othertests referenced to that calibration. About 40 L of fuel arerequired for a test, plus 12 L for the break-in.7.2 Reference OilsASTM 601 and 605 reference oils areused for ca
49、libration purposes.10ASTM 600 reference oil isused for break-in and as an assembly lubricant.10About 4 L ofreference oil is required to run a calibration test, and 0.4 L ofASTM 600 for a break-in. The properties of these oils aresummarized in Annex A2.7.3 Non-Reference OilAbout 4 L are required for a 50 htest, varying according to the number of test hours specified. Itis recommended that at least twice this amount be provided incase the test is rerun.7.4 GreaseOMC needle bearing grease or petroleum jelly.8. Calibration8.1 After 30
