ASTM D7094-17a Standard Test Method for Flash Point by Modified Continuously Closed Cup (MCCCFP) Tester.pdf

1、Designation: D7094 17aStandard Test Method forFlash Point by Modified Continuously Closed Cup(MCCCFP) Tester1This standard is issued under the fixed designation D7094; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las

2、t 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*1.1 This test method covers the determination of the flashpoint of fuels including diesel/biodiesel blends, lube oils,solven

3、ts, and other liquids by a continuously closed cup testerutilizing a specimen size of 2 mL, cup size of 7 mL, with aheating rate of 2.5 C per minute.1.1.1 Apparatus requiring a specimen size of 1 mL, cup sizeof 4 mL, and a heating rate of 5.5 C per minute must be runaccording to Test Method D6450.1.

4、2 This flash point test method is a dynamic method anddepends on definite rates of temperature increase. It is one ofthe many flash point test methods available and every flashpoint test method, including this one, is an empirical method.NOTE 1Flash point values are not a constant physical chemicalp

5、roperty of materials tested. They are a function of the apparatus design,the condition of the apparatus used, and the operational procedure carriedout. Flash point can, therefore, only be defined in terms of a standard testmethod and no general valid correlation can be guaranteed between resultsobta

6、ined by different test methods or where different test apparatus isspecified.1.3 This test method utilizes a closed but unsealed cup withair injected into the test chamber.1.4 This test method is suitable for testing samples with aflash point from 35 C to 225 C.NOTE 2Flash point determinations below

7、 35 C and above 225 Cmay be performed; however, the precision has not been determined belowand above these temperatures.1.5 If the users specification requires a defined flash pointmethod other than this method, neither this method nor anyother test method should be substituted for the prescribed te

8、stmethod without obtaining comparative data and an agreementfrom the specifier.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard. Temperatures are in degrees Celsius, pressure inkilo-Pascals.1.7 This standard does not purport

9、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, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.For specific warning statements, s

10、ee 7.2, 8.5, and 10.1.2.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organizat

11、ion TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D93 Test Methods for Flash Point by Pensky-MartensClosed Cup TesterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD6

12、450 Test Method for Flash Point by Continuously ClosedCup (CCCFP) TesterD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialE300 Practice for Sampling Industrial Chemicals2.2 ISO Standards:3ISO

13、Guide 34 Quality Systems Guidelines for the Produc-tion of Reference MaterialsISO Guide 35 Certification of Reference MaterialsGeneraland Statistical Principles3. Terminology3.1 Definitions:1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubr

14、icants and is the direct responsibility ofSubcommittee D02.08 on Volatility.Current edition approved Dec. 1, 2017. Published February 2018. Originallyapproved in 2004. Last previous edition approved in 2017 as D7094 17. DOI:10.1520/D7094-17A.2For referenced ASTM standards, visit the ASTM website, ww

15、w.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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.a

16、nsi.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 StatesThis international standard was developed in accordance with internationally recognized principles on standardizat

17、ion established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.1.1 dynamic, adjthe condition where the vapor abovethe test specimen and the test specimen are

18、 not in temperatureequilibrium at the time at which the ignition source is applied.3.1.2 flash point, nin flash point test methods, the lowesttemperature of the test specimen, adjusted to account forvariations in atmospheric pressure from 101.3 kPa, at whichapplication of an ignition source causes t

19、he vapors of the testspecimen to ignite under specified conditions of test.3.1.2.1 DiscussionFor the purpose of this test method, thetest specimen is deemed to have flashed when the hot flame ofthe ignited vapor causes an instantaneous pressure increase ofat least 20 kPa inside the closed measuring

20、chamber.4. Summary of Test Method4.1 The lid of the test chamber is regulated to a temperatureat least 18 C below the expected flash point.A2 mL 6 0.2 mLtest specimen of a sample is introduced into the sample cup.Both specimen and cup are at a temperature at least 18 Cbelow the expected flash point;

21、 cooled if necessary. The cup isthen raised and pressed onto the lid of specified dimensions toform the continuously closed but unsealed test chamber with anoverall volume of 7.0 mL 6 0.3 mL.4.2 After closing the test chamber, the temperatures of thetest specimen and the regulated lid are allowed to

22、 equilibrate towithin 1 C. Then the lid is heated at a prescribed, constantrate. For the flash tests, a high voltage arc of defined energy isdischarged inside the test chamber at regular intervals. Aftereach ignition, a variable amount of air (see Table 1)isintroduced into the test chamber to provid

23、e the necessaryoxygen for the next flash test. The pressure inside the continu-ously closed but unsealed test chamber remains at ambientbarometric pressure except for the short time during the airintroduction and at a flash point.4.3 After each arc application, the instantaneous pressureincrease abo

24、ve the ambient barometric pressure inside the testchamber is monitored. When the pressure increase exceeds20 kPa, the temperature at that point is recorded as theuncorrected flash point, which is then corrected to barometricpressure.5. Significance and Use5.1 The flash point temperature is one measu

25、re of thetendency of the test specimen to form a flammable mixturewith air under controlled laboratory conditions. It is only oneof a number of properties which must be considered inassessing the overall flammability hazard of a material.5.2 Flash point is used in shipping and safety regulations tod

26、efine flammable and combustible materials and for classifica-tion purposes. This definition may vary from regulation toregulation. Consult the particular regulation involved for pre-cise definitions of these classifications.5.3 This test method can be used to measure and describethe properties of ma

27、terials in response to heat and an ignitionsource under controlled laboratory conditions and shall not beused to describe or appraise the fire hazard or fire risk ofmaterials under actual fire conditions. However, results of thistest method may be used as elements of a fire risk assessment,which tak

28、es into account all of the factors which are pertinentto an assessment of the fire hazard of a particular end use.5.4 Flash point can also indicate the possible presence ofhighly volatile and flammable materials in a relatively non-volatile or nonflammable material, such as the contaminationof lubri

29、cating oils by small amounts of diesel fuel or gasoline.This test method was designed to be more sensitive to potentialcontamination than Test Method D6450.6. Apparatus6.1 Flash Point Apparatus, Continuously Closed CupOperationThe type of apparatus suitable for use in this testmethod employs a lid o

30、f solid brass, the temperature of whichis controlled electrically. Two temperature sensors for thespecimen and the lid temperatures, respectively, two arc pinsfor a high voltage arc, and a connecting tube for the pressuremonitoring and the air introduction are incorporated in the lid.Associated equi

31、pment for electrically controlling the chambertemperature is used, and a digital readout of the specimentemperature is provided. The apparatus and its critical elementsare shown in Figs. A1.1 and A1.2.6.1.1 Test ChamberThe test chamber is formed by thesample cup and the temperature-controlled lid, a

32、nd shall havean overall volume of 7 mL 6 0.3 mL.Ametal-to-metal contactbetween the lid and the sample cup shall provide good heatcontact but allow ambient barometric pressure to be maintainedinside the test chamber during the test. Critical dimensions areshown in Fig. A1.2. The pressure inside the m

33、easuring cham-ber during the temperature increase is monitored. A seal that istoo tight results in a pressure increase above ambient due to thetemperature and the vapor pressure of the sample. A poor heatcontact results in a bigger temperature difference between thesample and the heated lid.6.1.2 Sa

34、mple CupThe sample cup shall be made ofnickel-plated aluminum or other material with similar heatconductivity. It shall have an overall volume of7mL6 0.3 mL and shall be capable of containing2mL6 0.2 mL of sample. The critical dimensions and re-quirements are shown in Fig. A1.2.6.1.3 Specimen Temper

35、ature SensorThe specimen tem-perature sensor (Fig. A1.1) shall be a thermocouple (NiCr-Nior similar) in stainless steel of 1 mm diameter with a responsetime of t(90) = 3 s. It shall be immersed to a depth of at least2 mm into the specimen. It shall have a resolution of 0.1 C anda minimum accuracy of

36、 60.2 C, preferably with a digitalreadout.TABLE 1 Volume of Introduced Air as a Function ofSample TemperatureSample TemperatureRange (C)Introduced Volumeof Air (mL)below 80 080 to below 150 0.5 0.15150 to below 200 1 0.2200 to below 300 1.5 0.3300 and above 2 0.4D7094 17a26.1.4 Magnetic StirringThe

37、apparatus shall have provi-sions for stirring of the sample. A rotating magnet outside thesample cup shall drive a small stirring magnet which is insertedinto the sample cup after sample introduction. The stirringmagnet shall have a diameter of 3 mm 6 0.2 mm and a lengthof 12 mm 6 1 mm. The rotation

38、 speed of the driving magnetshall be between 250 r min and 270 r min.6.1.5 Air IntroductionThe apparatus shall have provisionsfor introduction of air immediately after each flash test. The airshall be introduced by a short air pulse from a small membranecompressor by means of a T-inlet in the connec

39、ting tube to thepressure transducer. The volume of the introduced air, from0.5 mL to 2 mL, is dependent on the sample temperature (seeTable 1).6.1.6 Electrical heating and thermoelectric cooling of the lid(see the Peltier element shown in Fig. A1.1) shall be used toregulate the temperature of the te

40、st chamber for the duration ofthe test. The temperature regulation shall have a minimumaccuracy of 60.2 C.6.1.7 A high voltage electric arc shall be used for theignition of the flammable vapor. The energy of the arc shall be1.3 J 6 0.3 J (1.3 Ws 6 0.3 Ws) per arc and the energy shall beapplied withi

41、n 19 m s 6 2 m s. (WarningBecause samplescontaining low flash material or having a flash point below thepreset initial temperature can oversaturate the vapor inside thechamber and hence prohibit the detection of a flash point in thechosen range, a precautionary arc set at 5 C intervals isrequired wh

42、ile the lid and sample cup temperatures areequalizing.)6.1.8 The pressure transducer for the flash point detectionshall be connected to the connecting tube in the lid and shallhave a minimum operational range from 80 kPa to 177 kPawith a minimum resolution of 0.1 kPa and a minimum accu-racy of 60.5

43、kPa. It shall be capable of detecting an instanta-neous pressure increase above barometric pressure of a mini-mum of 20 kPa within 100 m s.NOTE 3The monitoring of the instantaneous pressure increase abovebarometric pressure is one of several methods to determine a flash insidethe test chamber. A pre

44、ssure increase of 20 kPa corresponds to a flamevolume of approximately 2.5 mL.NOTE 4An automatic barometric correction, which is performedaccording to the procedure described in 12.1, can be installed in the tester.The absolute pressure reading of the pressure transducer described in 6.1.8may be use

45、d for the correction.6.1.9 The introduction of a test specimen of 2.0 mL 60.2 mL shall be accomplished by the use of a pipette or syringeof the required accuracy.7. Reagents and Materials7.1 Purity of ReagentsUse only chemicals of purity speci-fied in Table X1.1. Unless otherwise indicated, it is in

46、tendedthat all reagents conform to the specifications of the Committeeon Analytical Reagents of the American Chemical Societywhere such specifications are available.4Other grades may beused, provided it is first ascertained that the reagent is ofsufficient purity to permit its use without lessening

47、the accu-racy of the determination.7.1.1 Anisole(WarningSee 7.2.)7.1.2 Dodecane(WarningSee 7.2.)7.2 Cleaning SolventsUse only noncorrosive solvents ca-pable of cleaning the sample cup and the lid. Two commonlyused solvents are toluene and acetone. (WarningAnisole,dodecane, toluene, acetone, and many

48、 solvents are flammableand are health hazards. Dispose of solvents and waste materialin accordance with local regulations.)8. Sampling8.1 Obtain at least a 50 mL sample from a bulk test site inaccordance with the instructions given in Practice D4057,D4177,orE300. Store the sample in a clean, tightly

49、 sealedcontainer at a low temperature.8.2 Do not store samples for an extended period of time ingas-permeable containers such as plastic, because volatilematerial may diffuse through the walls of the container.Discard samples in leaky containers and obtain new samples.8.3 Erroneously high flash points can be obtained whenprecautions are not taken to avoid loss of volatile material. Donot open containers unnecessarily. Do not make a transferunless the sample temperature is at least 18 C below theexpected flash point. When