1、Designation: D56 16aStandard Test Method forFlash Point by Tag Closed Cup Tester1This standard is issued under the fixed designation D56; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in parent
2、heses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.INTRODUCTIONTo ensure an acceptable precision, this dynamic flash point test
3、method employs a prescribed rateof temperature rise for the material under test. The rate of heating may not in all cases give theprecision quoted in the test method because of the low thermal conductivity of certain materials. Toimprove the prediction of flammability, Test Method D3941, which utili
4、zes a slower heating rate, wasdeveloped. Test Method D3941 provides conditions closer to equilibrium where the vapor above theliquid and the liquid are at about the same temperature. If a specification requires Test Method D56,do not change to Test Method D3941 or other test method without permissio
5、n from the specifier.Flash point values are a function of the apparatus design, the condition of the apparatus used, andthe operational procedure carried out. Flash point can therefore only be defined in terms of a standardtest method, and no general valid correlation can be guaranteed between resul
6、ts obtained by differenttest methods, or with test apparatus different from that specified.1. Scope*1.1 This test method covers the determination of the flashpoint, by tag manual and automated closed testers, of liquidswith a viscosity below 5.5 mm2/s (cSt) at 40 C (104 F), orbelow 9.5 mm2/s (cSt) a
7、t 25 C (77 F), and a flash point below93 C (200 F).1.1.1 For the closed-cup flash point of liquids with thefollowing properties: a viscosity of 5.5 mm2/s (cSt) or more at40 C (104 F); a viscosity of 9.5 mm2/s (cSt) or more at 25 C(77 F); a flash point of 93 C (200 F) or higher; a tendency toform a s
8、urface film under test conditions; or containingsuspended solids, Test Method D93 can be used.1.1.2 For cut-back asphalts refer to Test Methods D1310and D3143.NOTE 1The U.S. Department of Transportation (RSTA)2and U.S.Department of Labor (OSHA) have established that liquids with a flashpoint under 3
9、7.8 C (100 F) are flammable as determined by this testmethod for those liquids that have a viscosity less than 5.5 mm2/s (cSt) at40 C (104 F) or 9.5 mm2/s (cSt) or less at 25 C (77 F), or do notcontain suspended solids or do not have a tendency to form a surface filmwhile under test. Other flash poi
10、nt classifications have been established bythese departments for liquids using this test method.1.2 This test method can be used to measure and describethe properties of materials, products, or assemblies in responseto heat and flame under controlled laboratory conditions andcannot be used to descri
11、be or appraise the fire hazard or firerisk of materials, products, or assemblies under actual fireconditions. However, results of this test method can be used aselements of fire risk assessment that takes into account all ofthe factors that are pertinent to an assessment of the fire hazardof a parti
12、cular end use.1.3 Related standards are Test Methods D93, D1310,D3828, D3278, and D3941.1.4 The values stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly.1.5 WARNINGMercury has been designated by manyregulatory agencies as a hazardous material t
13、hat can causecentral 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 EPAswe
14、bsitehttp:/www.epa.gov/mercury/faq.htmfor addi-tional information. Users should be aware that selling mercury1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.08 on Volatility.Curre
15、nt edition approved Oct. 1, 2016. Published October 2016. Originallyapproved in 1918. Last previous edition approved in 2016 as D56 16. DOI:10.1520/D0056-16A.2For information on United States Department of Transportation regulations, seeCodes of United States Regulation 49 CFR Chapter 1 and for info
16、rmation on UnitedStates Department of Labor regulations, see Code of United States Regulation 29CFR Chapter XVII. Each of these items are revised annually and may be procuredfrom the Superintendent of Documents, Government Printing Office, Washington,DC 20402.*A Summary of Changes section appears at
17、 the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1and/or mercury containing products into your state or countrymay be prohibited by law.1.6 This standard does not purport to address all of thesafety concerns, if
18、 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. For specificwarning statements see 8.2, 8.3, 9.5, 12.5, and refer to MaterialSafety Data
19、Sheets.2. Referenced Documents2.1 ASTM Standards:3D93 Test Methods for Flash Point by Pensky-MartensClosed Cup TesterD1310 Test Method for Flash Point and Fire Point of Liquidsby Tag Open-Cup ApparatusD3143 Test Method for Flash Point of Cutback Asphalt withTag Open-Cup ApparatusD3278 Test Methods f
20、or Flash Point of Liquids by SmallScale Closed-Cup ApparatusD3828 Test Methods for Flash Point by Small Scale ClosedCup TesterD3941 Test Method for Flash Point by the EquilibriumMethod With a Closed-Cup ApparatusD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD6299 Practice for
21、Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsE1 Specification for ASTM Liquid-in-Glass ThermometersE502
22、Test Method for Selection and Use of ASTM Stan-dards for the Determination of Flash Point of Chemicalsby Closed Cup Methods2.2 Federal Test Method Standards:4Method 1101, Federal Test Method Standard No. 791bMethod 4291, Federal Test Method Standard No. 141A2.3 ISO Standards:5Guide 34 General requir
23、ements for the competence of refer-ence material producersGuide 35 Reference materialsGeneral and statistical prin-ciples for certification3. Terminology3.1 Definitions:3.1.1 flash point, nin flash point test methods, the lowesttemperature of the test specimen, adjusted to account forvariations in a
24、tmospheric pressure from 101.3 kPa, at whichapplication of an ignition source causes the vapors of the testspecimen to ignite under specified conditions of test.3.1.1.1 DiscussionThe specimen is deemed to haveflashed when a flame appears and instantaneously propagatesitself over the entire surface o
25、f the fluid.3.1.1.2 DiscussionWhen the ignition source is a testflame, the application of the test flame may cause a blue haloor an enlarged flame prior to the actual flash point. This is nota flash and should be ignored.3.2 Definitions of Terms Specific to This Standard:3.2.1 dynamic (non-equilibri
26、um)in this type of flash pointapparatus, the condition of the vapor above the specimen andthe specimen are not at the same temperature at the time thatthe ignition source is applied.3.2.1.1 DiscussionThis is primarily caused by the heatingof the specimen at the constant prescribed rate with the vapo
27、rtemperature lagging behind the specimen temperature. Theresultant flash point temperature is generally within the repro-ducibility of the test method.3.2.2 equilibriumin that type of flash point apparatus ortest method, the vapor above the specimen and the specimenare at the same temperature at the
28、 time the ignition source isapplied.3.2.2.1 DiscussionThis condition may not be fullyachieved in practice, since the temperature is not uniformthroughout the specimen and the test cover and shutter aregenerally cooler.4. Summary of Test Method4.1 The specimen is placed in the cup of the tester and,
29、withthe lid closed, heated at a slow constant rate.An ignition sourceis directed into the cup at regular intervals. The flash point istaken as the lowest temperature at which application of theignition source causes the vapor above the specimen to ignite.5. Significance and Use5.1 Flash point measur
30、es the tendency of the specimen toform a flammable mixture with air under controlled laboratoryconditions. It is only one of a number of properties that shall beconsidered in assessing the overall flammability hazard of amaterial.5.2 Flash point is used in shipping and safety regulations todefine fl
31、ammable and combustible materials. One shouldconsult the particular regulation involved for precise defini-tions of these classes.5.3 Flash point can indicate the possible presence of highlyvolatile and flammable materials in a relatively nonvolatile ornonflammable material. For example, an abnormal
32、ly low flashpoint on a sample of kerosene can indicate gasoline contami-nation.6. Apparatus (Manual Instrument)6.1 Tag Closed TesterThe apparatus is shown in Fig. 1 anddescribed in detail in Annex A1.6.2 ShieldA shield 460 mm (18 in.) square and 610 mm(24 in.) high, open in front, is recommended.3Fo
33、r 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.4Available from Superintendent of Documents, U.S. Government Pri
34、ntingOffice, Washington, DC 20402.5Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.D56 16a26.3 Temperature Measuring DeviceA liquid-in-glassthermometer, as prescribed in Table 1, or an electronic tem-perature measuring dev
35、ice such as a resistance device orthermocouple. The device shall exhibit the same temperatureresponse as the liquid-in-glass thermometer.NOTE 2Whenever thermometers complying withASTM requirementsare not available, thermometers complying with the requirements for TheInstitute of Petroleum thermomete
36、r IP 15C PM-Low can be used.7. Sampling7.1 Erroneously high flash points will be obtained whenprecautions are not taken to avoid the loss of volatile material.Containers should not be opened unnecessarily to prevent lossof volatile material and possible introduction of moisture.Transfers should not
37、be made unless the sample temperature isat least 10 C (18 F) below the expected flash point. Whenpossible, flash point shall be the first test performed on asample and the sample must be stored at low temperature.7.2 Do not store samples in gas-permeable containers sincevolatile materials may diffus
38、e through the walls of the enclo-sure. Samples in leaky containers are suspect and not a sourceof valid results.7.3 At least 50 mL of sample is required for each test. Referto sampling information in Practice D4057.8. Preparation of Apparatus (Manual)8.1 Support the manual apparatus on a level stead
39、y surface,such as a table. Unless tests are made in a draft-free room orcompartment, surround the tester on three sides by the shieldfor protection from drafts. Tests are not to be made in alaboratory draft hood or near ventilators.8.2 Natural gas and bottled gas flame and electric ignitorshave been
40、 found acceptable for use as the ignition source.(WarningGas pressure supplied to the apparatus must not beallowed to exceed 3 kPa (12 in.) of water pressure.)8.3 For flash points below 13 C (55 F) or above 60 C(140 F), use as a bath liquid a 1 + 1 mixture of water andethylene glycol (WarningEthylen
41、e GlycolPoison. Harm-ful or fatal if swallowed. Vapor harmful. Avoid contact withskin.) For flash points between 13 C (55 F) and 60 C(140 F), either water or a water-glycol mixture can be used asbath liquid. The temperature of the liquid in the bath shall beat least 10 C (18 F) below the expected fl
42、ash point at the timeof introduction of the sample into the test cup. Do not cool bathliquid by direct contact with dry ice (solid carbon dioxide).NOTE 3Due to possible difficulty in maintaining the prescribed rate oftemperature rise and due to the formation of ice on the lid, results by thistest me
43、thod for samples having flash points below 0 C (32 F) may beunreliable. Trouble due to ice formation on the slide can be minimized bycarefully lubricating the slide shutter with high-vacuum silicone lubricant.8.4 Verify the performance of the manual apparatus (or in11.2.3, the automated apparatus) a
44、t least once per year bydetermining the flash point of a certified reference material(CRM), such as those listed in Annex A2, which is reasonablyclose to the expected temperature range of the samples to betested. The material shall be tested according to the procedureof this test method and the obse
45、rved flash point obtained in 9.5shall be corrected for barometric pressure (see Section 13). Theflash point obtained shall be within the limits stated in TableA2.1 for the identified CRM or within the limits calculated foran unlisted CRM (see Annex A2).8.5 Once the performance of the apparatus has b
46、eenverified, the flash point of secondary working standards(SWSs) can be determined along with their control limits.FIG. 1 Tag Closed Flash Tester (Manual)TABLE 1 ThermometersFor testsBelow 4 C(40 F)At4Cto49C(40 F to120 F)Above 49 C(120 F)Use ASTMThermometerA57C or (57F) 9C or (9F)57C or (57F)9C or
47、(9F)AComplete specifications for these thermometers are given in Specification E1.D56 16a3These secondary materials can then be utilized for morefrequent performance checks (see Annex A2).8.6 When the flash point obtained is not within the limitsstated in 8.4 or 8.5, check the condition and operatio
48、n of theapparatus to ensure conformity with the details listed in AnnexA1, especially with regard to tightness of the lid (see A1.1.3),the action of the shutter, the position of the ignition source (seeA1.1.3.3), and the angle and position of the temperaturemeasuring device (see A1.1.3.4). After any
49、 adjustment, repeatthe test in 8.4 using fresh test specimen, with special attentionto the procedural details prescribed in the test method.9. Procedure (Manual)9.1 Using a graduated cylinder and taking care to avoidwetting the cup above the final liquid level, measure50 mL 6 0.5 mL of the sample into the cup, both the sampleand graduated cylinder being precooled, when necessary, sothat the specimen temperature at the time of measurement willbe 27 C 6 5 C (80 F 6 10 F) or at least 10 C (18 F)below the expected fl
