1、Designation: D7094 16Standard 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 last
2、 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, lube oils, solvents and other liquids by acontinuou
3、sly closed cup tester utilizing a specimen size of2 mL, cup size of 7 mL, with a heating rate of 2.5 C perminute.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 D6450.1.2 This flash point test method is a
4、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 chemicalproperty of materials tested. They ar
5、e 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 resultsobtained by different test methods or wh
6、ere 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 35 C and above 225 Cmay be performe
7、d; 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 testmethod without obtaining comparati
8、ve 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 to address all of thesafety concerns
9、, 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. For specificwarning statements, see 7.2, 8.5, and 10.1.2.2. Referenced Documents2.1 A
10、STM 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 ProductsD6450 Test Method for Flash Point by Continuously ClosedCup (CCCFP) TesterD67
11、08 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 Guide 34 Quality Systems Guidelines for the Produc-tion of Reference Materi
12、alsISO Guide 35 Certification of Reference MaterialsGeneraland Statistical Principles3. Terminology3.1 Definitions:3.1.1 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 whichapplicatio
13、n of an ignition source causes the vapors of the testspecimen to ignite under specified conditions of test.3.1.1.1 DiscussionFor the purpose of this test method, thetest specimen is deemed to have flashed when the hot flame of1This test method is under the jurisdiction of ASTM Committee D02 onPetrol
14、eum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.08 on Volatility.Current edition approved June 1, 2016. Published July 2016. Originally approvedin 2004. Last previous edition approved in 2012 as D7094 20121. DOI:10.1520/D7094-16.2For referenced ASTM sta
15、ndards, 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.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floo
16、r, 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 States1the ignited vapor causes an instantaneous pressure increase ofat least 20 kPa i
17、nside the closed measuring chamber.3.1.2 dynamic, adjthe condition where the vapor abovethe test specimen and the test specimen are not in temperatureequilibrium at the time at which the ignition source is applied.4. Summary of Test Method4.1 The lid of the test chamber is regulated to a temperature
18、at 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; cooled if necessary. The cup isthen raised and pressed onto the lid of specified dimensions t
19、oform 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 equilibrate towithin 1 C. Then the lid is heated at a prescribed, constantrate. For the flash
20、 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 provide the necessaryoxygen for the next flash test. The pressure inside the continu-ously closed bu
21、t 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 above the ambient barometric pressure inside the testchamber is monitored. When the pressure incr
22、ease 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 measure of thetendency of the test specimen to form a flammable mixturewith air under controlled la
23、boratory 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 todefine flammable and combustible materials and for classifica-tion purposes. This definition ma
24、y 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 materials in response to heat and an ignitionsource under controlled laboratory conditions and s
25、hall 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 takes into account all of the factors which are pertinentto an assessment of the fire hazard of a
26、 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 lubricating oils by small amounts of diesel fuel or gasoline.This test method was designed to be mo
27、re 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 of solid brass, the temperature of whichis controlled electrically. Two temperature sensors for
28、 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 equipment for electrically controlling the chambertemperature is used, and a digital readout of th
29、e 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 and shall have anoverall volume of 7 mL 6 0.3 mL. A metal to metal contactbetween the lid and th
30、e 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 measuring cham-ber during the temperature increase is monitored. A seal that istoo tight resul
31、ts 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 Sample CupThe sample cup shall be made ofnickel-plated aluminum or other material with similar
32、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 Temperature SensorThe specimen tem-perature sensor (Fig. A1.1) shall be a thermocouple (NiCr-Nior s
33、imilar) 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 60.2 C, preferably with a digitalreadout.6.1.4 Magnetic StirringThe apparatus shall have pro
34、vi-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 speed of the driving ma
35、gnetshall 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 airTABLE 1 Volume of Introduced Air as a Function ofSample TemperatureSample TemperatureRange (C)Introduced Volumeof Air (mL)below 80 0
36、80 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 162shall be introduced by a short air pulse from a small membranecompressor by means of a T-inlet in the connecting tube to thepressure transducer. The volume of the introduced air, from0.5 mL to 2 mL, is
37、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 test chamber for the duration ofthe test. The temperature regulation shall have a minimumaccurac
38、y of 6 0.2C.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 within 19 m s 6 2 m s. (WarningBecause samplescontaining low flash material or having a flash point
39、 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 while the lid and sample cup temperatures areequalizing.)6.1.8 The pressure transducer for the f
40、lash 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 kPa. It shall be capable of detecting an instanta-neous pressure increase above barometric pre
41、ssure 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 pressure increase of 20 kPa corresponds to a flamevolume of approximately 2.5 mL.NOTE 4An automat
42、ic 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 used for the correction.6.1.9 The introduction of a test specimen of 2.0 mL 60.2 mL shall be acco
43、mplished 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 intendedthat all reagents conform to the specifications of the Committeeon Analytical Reagents o
44、f 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 the accu-racy of the determination.7.1.1 Anisole(WarningSee 7.2.)7.1.2 Dodecane(WarningSee 7.2
45、.)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 solvents are flammableand are health hazards. Dispose of solvents and waste materialin accord
46、ance with local regulations.)8. Sampling8.1 Obtain at least a 50 mL sample from a bulk test site inaccordance with the instructions given in Practices D4057,D4177,orE300. Store the sample in a clean, tightly sealedcontainer at a low temperature.8.2 Do not store samples for an extended period of time
47、 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 o
48、pen containers unnecessarily. Do not make a transferunless the sample temperature is at least 18 C below theexpected flash point. When possible, perform the flash point asthe first test.8.4 Samples of very viscous materials may be warmed untilthey are reasonably fluid before they are tested. However
49、, donot heat the unsealed sample above a temperature of 18 Cbelow its expected flash point.8.5 Samples containing dissolved or free water may bedehydrated with calcium chloride or by filtering through aqualitative filter paper or a loose plug of dry absorbent cotton.Warming the sample is permitted, but it should not be heatedabove a temperature of 18 C below its expected flash point.(WarningBecause samples containing volatile material willlose volatiles and then yield incorrectly high flash points, thetreatment described in 8.4
