1、Designation: D7094 17D7094 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 yea
2、r 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*1.1 This test method covers the determination of the flash point of fuels, fuels including diesel/biodiesel blends,
3、lube oils,solvents, and other liquids by a continuously closed cup tester utilizing a specimen size of 2 mL, cup size of 7 mL, with a heatingrate of 2.5 C per minute.1.1.1 Apparatus requiring a specimen size of 1 mL, cup size of 4 mL, and a heating rate of 5.5 C per minute must be runaccording to Te
4、st Method D6450.1.2 This flash point test method is a dynamic method and depends on definite rates of temperature increase. It is one of the manyflash point test methods available and every flash point test method, including this one, is an empirical method.NOTE 1Flash point values are not a constan
5、t physical chemical property of materials tested. They are a function of the apparatus design, the conditionof the apparatus used, and the operational procedure carried out. Flash point can, therefore, only be defined in terms of a standard test method and nogeneral valid correlation can be guarante
6、ed between results obtained by different test methods or where different test apparatus is specified.1.3 This test method utilizes a closed but unsealed cup with air injected into the test chamber.1.4 This test method is suitable for testing samples with a flash point from 35 C to 225 C.NOTE 2Flash
7、point determinations below 35 C and above 225 C may be performed; however, the precision has not been determined below andabove these temperatures.1.5 If the users specification requires a defined flash point method other than this method, neither this method nor any othertest method should be subst
8、ituted for the prescribed test method without obtaining comparative data and an agreement from thespecifier.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.Temperatures are in degrees Celsius, pressure in kilo-Pascals.1.7
9、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 to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior
10、 to use. For specific warning statements, see 7.2, 8.5, and 10.1.2.1.8 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendat
11、ions issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D93 Test Methods for Flash Point by Pensky-Martens Closed Cup TesterD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177 Practice for Automatic Sam
12、pling of Petroleum and Petroleum ProductsD6450 Test Method for Flash Point by Continuously Closed Cup (CCCFP) TesterD6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property of a MaterialE300 Practice for Samplin
13、g Industrial Chemicals1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.08 on Volatility.Current edition approved May 1, 2017Dec. 1, 2017. Published June 2017February 2018. Origina
14、lly approved in 2004. Last previous edition approved in 20162017 asD7094 16.D7094 17. DOI: 10.1520/D7094-17.10.1520/D7094-17A.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information,
15、refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard 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
16、 changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases 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, 10
17、0 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ISO Standards:3ISO Guide 34 Quality Systems Guidelines for the Production of Reference MaterialsISO Guide 35 Certification of Reference MaterialsGeneral and Statistical Principles3. Terminology3.1 Definitions:3.1.1
18、 dynamic, adjthe condition where the vapor above the test specimen and the test specimen are not in temperatureequilibrium at the time at which the ignition source is applied.3.1.2 flash point, nin flash point test methods, the lowest temperature of the test specimen, adjusted to account for variati
19、onsin atmospheric pressure from 101.3 kPa, at which application of an ignition source causes the vapors of the test specimen to igniteunder specified conditions of test.3.1.2.1 DiscussionFor the purpose of this test method, the test specimen is deemed to have flashed when the hot flame of the ignite
20、d vapor causesan instantaneous pressure increase of at least 20 kPa inside the closed measuring chamber.4. Summary of Test Method4.1 The lid of the test chamber is regulated to a temperature at least 18 C below the expected flash point. A 2 mL 6 0.2 mLtest specimen of a sample is introduced into the
21、 sample cup. Both specimen and cup are at a temperature at least 18 C below theexpected flash point; cooled if necessary. The cup is then raised and pressed onto the lid of specified dimensions to form thecontinuously closed but unsealed test chamber with an overall volume of 7.0 mL 6 0.3 mL.4.2 Aft
22、er closing the test chamber, the temperatures of the test specimen and the regulated lid are allowed to equilibrate to within1 C. Then the lid is heated at a prescribed, constant rate. For the flash tests, a high voltage arc of defined energy is dischargedinside the test chamber at regular intervals
23、. After each ignition, a variable amount of air (see Table 1) is introduced into the testchamber to provide the necessary oxygen for the next flash test. The pressure inside the continuously closed but unsealed testchamber remains at ambient barometric pressure except for the short time during the a
24、ir introduction and at a flash point.4.3 After each arc application, the instantaneous pressure increase above the ambient barometric pressure inside the testchamber is monitored.When the pressure increase exceeds 20 kPa, the temperature at that point is recorded as the uncorrected flashpoint, which
25、 is then corrected to barometric pressure.5. Significance and Use5.1 The flash point temperature is one measure of the tendency of the test specimen to form a flammable mixture with air undercontrolled laboratory conditions. It is only one of a number of properties which must be considered in assess
26、ing the overallflammability hazard of a material.5.2 Flash point is used in shipping and safety regulations to define flammable and combustible materials and for classificationpurposes. This definition may vary from regulation to regulation. Consult the particular regulation involved for precise def
27、initionsof these classifications.5.3 This test method can be used to measure and describe the properties of materials in response to heat and an ignition sourceunder controlled laboratory conditions and shall not be used to describe or appraise the fire hazard or fire risk of materials underactual f
28、ire conditions. However, results of this test method may be used as elements of a fire risk assessment, which takes intoaccount all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.3 Available from American National Standards Institute (ANSI), 25 W. 43rd
29、 St., 4th Floor, New York, NY 10036, http:/www.ansi.org.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 17a25.4 Flash poi
30、nt can also indicate the possible presence of highly volatile and flammable materials in a relatively nonvolatile ornonflammable material, such as the contamination of lubricating oils by small amounts of diesel fuel or gasoline. This test methodwas designed to be more sensitive to potential contami
31、nation than Test Method D6450.6. Apparatus6.1 Flash Point Apparatus, Continuously Closed Cup OperationThe type of apparatus suitable for use in this test methodemploys a lid of solid brass, the temperature of which is controlled electrically. Two temperature sensors for the specimen and thelid tempe
32、ratures, respectively, two arc pins for a high voltage arc, and a connecting tube for the pressure monitoring and the airintroduction are incorporated in the lid. Associated equipment for electrically controlling the chamber temperature is used, and adigital readout of the specimen temperature is pr
33、ovided. The apparatus and its critical elements are shown in Figs.A1.1 and A1.2.6.1.1 Test ChamberThe test chamber is formed by the sample cup and the temperature-controlled lid, and shall have an overallvolume of 7 mL 6 0.3 mL.Ametal-to-metal contact between the lid and the sample cup shall provide
34、 good heat contact but allowambient barometric pressure to be maintained inside the test chamber during the test. Critical dimensions are shown in Fig. A1.2.The pressure inside the measuring chamber during the temperature increase is monitored. A seal that is too tight results in apressure increase
35、above ambient due to the temperature and the vapor pressure of the sample.Apoor heat contact results in a biggertemperature difference between the sample and the heated lid.6.1.2 Sample CupThe sample cup shall be made of nickel-plated aluminum or other material with similar heat conductivity.It shal
36、l have an overall volume of 7 mL 6 0.3 mL and shall be capable of containing 2 mL 6 0.2 mL of sample. The criticaldimensions and requirements are shown in Fig. A1.2.6.1.3 Specimen Temperature SensorThe specimen temperature sensor (Fig.A1.1) shall be a thermocouple (NiCr-Ni or similar)in stainless st
37、eel of 1 mm diameter with a response time of t(90) = 3 s. It shall be immersed to a depth of at least 2 mm into thespecimen. It shall have a resolution of 0.1 C and a minimum accuracy of 60.2 C, preferably with a digital readout.6.1.4 Magnetic StirringThe apparatus shall have provisions for stirring
38、 of the sample. A rotating magnet outside the samplecup shall drive a small stirring magnet which is inserted into the sample cup after sample introduction. The stirring magnet shallhave a diameter of 3 mm 6 0.2 mm and a length of 12 mm 6 1 mm. The rotation speed of the driving magnet shall be betwe
39、en250 rmin and 270 rmin.6.1.5 Air IntroductionThe apparatus shall have provisions for introduction of air immediately after each flash test. The airshall be introduced by a short air pulse from a small membrane compressor by means of a T-inlet in the connecting tube to thepressure transducer. The vo
40、lume of the introduced air, from 0.5 mL to 2 mL, is dependent on the sample temperature (see Table1).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 of the test.
41、The temperature regulation shall have a minimum accuracyof 60.2 C.6.1.7 A high voltage electric arc shall be used for the ignition of the flammable vapor. The energy of the arc shall be 1.3 J 60.3 J (1.3 Ws 6 0.3 Ws) per arc and the energy shall be applied within 19 ms 6 2 ms. (WarningBecause sample
42、s containinglow flash material or having a flash point below the preset initial temperature can oversaturate the vapor inside the chamber andhence prohibit the detection of a flash point in the chosen range, a precautionary arc set at 5 C intervals is required while the lidand sample cup temperature
43、s are equalizing.)6.1.8 The pressure transducer for the flash point detection shall be connected to the connecting tube in the lid and shall havea minimum operational range from 80 kPa to 177 kPa with a minimum resolution of 0.1 kPa and a minimum accuracy of60.5 kPa.It shall be capable of detecting
44、an instantaneous pressure increase above barometric pressure of a minimum of 20 kPa within100 ms.NOTE 3The monitoring of the instantaneous pressure increase above barometric pressure is one of several methods to determine a flash inside thetest chamber. A pressure increase of 20 kPa corresponds to a
45、 flame volume of approximately 2.5 mL.NOTE 4An automatic barometric correction, which is performed according to the procedure described in 12.1, can be installed in the tester. Theabsolute pressure reading of the pressure transducer described in 6.1.8 may be used for the correction.6.1.9 The introdu
46、ction of a test specimen of 2.0 mL 6 0.2 mL shall be accomplished by the use of a pipette or syringe of therequired accuracy.7. Reagents and Materials7.1 Purity of ReagentsUse only chemicals of purity specified in Table X1.1. Unless otherwise indicated, it is intended that allreagents conform to the
47、 specifications of the Committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.4 Other grades may be used, provided it is first ascertained that the reagent is of sufficient purity topermit its use without lessening the accuracy of the determination.4
48、 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmaco
49、peia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.D7094 17a37.1.1 Anisole(WarningSee 7.2.)7.1.2 Dodecane(WarningSee 7.2.)7.2 Cleaning SolventsUse only noncorrosive solvents capable of cleaning the sample cup and the lid. Two commonly usedsolvents are toluene and acetone. (WarningAnisole, dodecane, toluene, acetone, and many solvents are flammable and are healthhazards. Dispose of solvents and waste material in accordance with local regulations.)8. Sampling8.1 Obtain at least a 50 mL sample f
