1、Designation: D7094 16D7094 17Standard 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
2、 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, lube oils, solvents, and other liquids by
3、a continuouslyclosed cup tester utilizing a specimen size of 2 mL, cup size of 7 mL, with a heating rate 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 Test Method D6450.1.2 This flash point test
4、 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 constant physical chemical property of materials
5、 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 guaranteed between results obtained by different
6、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 point determinations below 35 C and above
7、 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 substituted for the prescribed test method wit
8、hout 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 This standard does not purport to address
9、 all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific warning statements, see 7.2, 8.5, and 10.1.2.1.8
10、 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 Recommendations issuedby the World Trade Organization Technical Barriers to Trade
11、 (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 Sampling of Petroleum and Petroleum ProductsD6450 Test Method for Flash P
12、oint 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 Sampling Industrial Chemicals1 This test method is under the jurisdiction ofA
13、STM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.08 on Volatility.Current edition approved June 1, 2016May 1, 2017. Published July 2016June 2017. Originally approved in 2004. Last previous edition approved in 20122016 asD7094 2
14、012D7094 16.1. DOI: 10.1520/D7094-16.10.1520/D7094-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This do
15、cument 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 changes accurately, ASTM recommends that users consult prior editions a
16、s 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, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. Unit
17、ed 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 dynamic, adjthe condition where the vapor above the test specimen and t
18、he 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 variationsin atmospheric pressure from 101.3 kPa, at which application of an ig
19、nition 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 ignited vapor causesan instantaneous pressure increase of at least 20 kPa insi
20、de the closed measuring chamber.3.1.2 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.4. Summary of Test Method4.1 The lid of the test chamber is regulated to a temperature a
21、t least 18 C below the expected flash point. A 2 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 C below theexpected flash point; cooled if necessary. The cup is then raised and pressed onto the lid of specified dimension
22、s to form thecontinuously closed but unsealed test chamber with an overall volume of 7.0 mL 6 0.3 mL.4.2 After 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
23、 flash tests, a high voltage arc of defined energy is dischargedinside the test chamber at regular intervals. 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 c
24、losed but unsealed testchamber remains at ambient barometric pressure except for the short time during the air 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 pres
25、sure increase exceeds 20 kPa, the temperature at that point is recorded as the uncorrected flashpoint, which 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 underc
26、ontrolled laboratory conditions. It is only one of a number of properties which must be considered in assessing 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 d
27、efinition may vary from regulation to regulation. Consult the particular regulation involved for precise definitionsof 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 cond
28、itions and shall not be used to describe or appraise the fire hazard or fire risk of materials underactual fire 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 f
29、ire hazard of a particular end use.3 Available from American National Standards Institute (ANSI), 25 W. 43rd 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 t
30、o below 150 0.5 0.15150 to below 200 1 0.2200 to below 300 1.5 0.3300 and above 2 0.4D7094 1725.4 Flash point 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
31、 amounts of diesel fuel or gasoline. This test methodwas designed to be more sensitive to potential contamination 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
32、 temperature of which is controlled electrically. Two temperature sensors for the specimen and thelid temperatures, 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 elect
33、rically controlling the chamber temperature is used, and adigital readout of the specimen temperature is provided. 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 temperature-con
34、trolledlid, and shall have an overall volume of 7 mL 6 0.3 mL. A metal to metal metal-to-metal contact between the lid and the samplecup shall provide good heat contact but allow ambient barometric pressure to be maintained inside the test chamber during the test.Critical dimensions are shown in Fig
35、. A1.2. The pressure inside the measuring chamber during the temperature increase ismonitored. A seal that is too tight results in a pressure increase above ambient due to the temperature and the vapor pressure ofthe sample. A poor heat contact results in a bigger temperature difference between the
36、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 shall 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 s
37、hown 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 steel 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 resolu
38、tion 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 of the sample. A rotating magnet outside the samplecup shall drive a small stirring magnet which is inserted into the sample cup after sample intr
39、oduction. 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 between250 rmin and 270 rmin.6.1.5 Air IntroductionThe apparatus shall have provisions for introduction of air immediately after each flash test. The ai
40、rshall 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 volume 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 co
41、oling 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. The temperature regulation shall have a minimum accuracyof 6 0.2C.60.2 C.6.1.7 A high voltage electric arc shall be used for the ignition of the fl
42、ammable 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 samples containinglow flash material or having a flash point below the preset initial temperature can oversaturate the vapor inside the chamber an
43、dhence 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 temperatures 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
44、 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 an instantaneous pressure increase above barometric pressure of a minimum of 20 kPa within100 ms.NOTE 3The monitoring of the instantaneous p
45、ressure 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 flame volume of approximately 2.5 mL.NOTE 4An automatic barometric correction, which is performed according to the procedure described in 1
46、2.1, 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 introduction 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
47、 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 specifications of the Committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.4 Other grad
48、es 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 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of r
49、eagents not listed bythe American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.D7094 1737.1.1 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
