1、Designation: D61 15Standard Test Method forSoftening Point of Pitches (Cube-in-Water Method)1This standard is issued under the fixed designation D61; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A numb
2、er in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of the soft-ening point of pitches below 176 F (80 C). Pitches of highersoftening point should b
3、e tested by Test Method D2319 or TestMethod D3104.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport
4、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 and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D140 Pr
5、actice for Sampling Bituminous MaterialsD2319 Test Method for Softening Point of Pitch (Cube-in-Air Method)D3104 Test Method for Softening Point of Pitches (MettlerSoftening Point Method)E1 Specification for ASTM Liquid-in-Glass ThermometersE563 Practice for Preparation and Use of an Ice-Point Batha
6、s a Reference TemperatureE1137 Specification for Industrial Platinum Resistance Ther-mometersE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision LiquidsE2877 Guide for Digital Contact Thermometers3. Terminology3.1 Definitions:3.1.1 Digital Contact Thermometer (DCT),
7、nan electronicdevice consisting of a digital display and associated tempera-ture sensing probe.3.1.1.1 DiscussionThis device consists of a temperaturesensor connected to a measuring instrument; this instrumentmeasures the temperature-dependent quantity of the sensor,computes the temperature from the
8、 measured quantity, andprovides a digital output or display, or both, of the temperature.The temperature sensing probe is in contact with the materialwhose temperature is being measured. This device is some-times referred to as a digital thermometer.NOTE 1Portable electronic thermometers (PET) is an
9、 acronym some-times used to refer to a subset of the devices covered by this definition.4. Summary of Test Method4.1 Two cubes of pitch, supported on wire hooks, are heatedat a controlled rate in water in a glass container. The softeningpoint is defined as the mean of the temperatures at which thecu
10、bes sag downwards a distance of 25 mm.5. Significance and Use5.1 Pitch does not go through a solid-liquid phase changewhen heated, and therefore it does not have a true meltingpoint. As the temperature rises, pitch softens and becomes lessviscous. The softening point is arbitrarily defined and shall
11、 beestablished by a closely controlled method which shall becarefully followed if test results are to be reproducible.5.2 This test is useful in determining the consistency ofpitch as one element in establishing the uniformity of ship-ments or sources of supply.6. Apparatus6.1 MoldA mold suitable fo
12、r forming two12 in.(12.7 mm) cubes of pitch, having cylindrical core pins 12gauge (2.05 mm) in diameter located in the base plate of theassembly to produce accurately centered suspension holes inthe cubes. (See Fig. 1.)6.2 HooksTwo L-shaped hooks, made of 12 gauge(2.05 mm) copper wire. The foot of t
13、he hook shall be 1 in.(25 mm) long and at a right angle to the upright portion forinsertion into the center hole of the pitch cube.6.3 ContainerA glass vessel that can be heated, not lessthan 85 mm in diameter and 105 mm deep. (Astandard 600 mLlow-form beaker meets these requirements).1This test met
14、hod is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricantsand is the direct responsibility ofSubcommittee D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.Current edition approved July 1, 2015. Published July 2015. Originally approvedin 19
15、19. Last previous edition approved in 2010 as D61 75 (2010). DOI:10.1520/D0061-15.2For 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 pag
16、e onthe ASTM website.*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 States16.4 Temperature Measuring DeviceUse either a calibratedDCT meeting the requirements described in 6.4
17、.1 or liquid-in-glass thermometers described in 6.4.2. A DCT or calibratedliquid-in-glass thermometer shall be used as the thermometerfor temperature measurement independent of the instrumentstemperature control, and shall be located in the thermowell.NOTE 2The display device and sensor must be corr
18、ectly paired.Incorrect pairing will result in temperature measurement errors andpossibly irreversible damage to the electronics of the display.FIG. 1 Apparatus for Cube-in-Water MethodD611526.4.1 Digital Contact Thermometer Requirements:Criteria RequirementsDCT E2877 Class E, MinimumTemperature rang
19、e 2 C to 80 CDisplay resolution 0.1 CSensor type PRT, thermistor, Type E or T thermocoupleSensor, sheath Metal or glassSensor length Less than 12 mm in lengthImmersion depth 76 mmDisplay accuracy 0.2 C for combined probe and sensorResponse time Less than or equal to 30 s as defined in Specifica-tion
20、 E1137Drift Less than 0.2 C per yearCalibration error Less than 0.2 C over the range of intended useCalibration range 2 C to 80 CCalibration data 4 data points evenly distributed over the rangeand included in calibration reportCalibration report From a calibration laboratory with demonstratedcompete
21、ncy in temperature calibration which istraceable to a national calibration laboratory ormetrology standards body6.4.1.1 The DCT calibration drift shall be checked at leastannually by either measuring the ice point or against areference thermometer in a constant temperature bath at theprescribed imme
22、rsion depth to ensure compliance with 6.4.1.With respect to an ice bath, Practice E563 provides guidanceon the preparation and use of an ice bath. However, for this use,variance from the specific steps, such as water source, ispermitted provided preparation is consistent. The basis for thevariance i
23、s due to the ice bath reference being used for trackingchange in calibration not verification.NOTE 3When a DCTs calibration drifts in one direction over severalcalibration checks, that is, ice point, it may be an indication of deteriora-tion of the DCT.6.4.2 An ASTM Low Softening Point Thermometer h
24、avinga range from 2 C to 80 C and conforming to therequirements for Thermometer 15 as described in SpecificationE1 or E2251.6.4.2.1 Calibration CheckVerify thermometer at least an-nually against a reference thermometer in a constant tempera-ture bath or an ice bath. The thermometer is to be inserted
25、 to itsimmersion depth. If using an ice bath, the ice point reading isto be taken within 60 min after the thermometer has been at testtemperature for at least 3 min. If the corrected temperaturereading deviates from the reference thermometer or the icepoint, then repeat this calibration check. If th
26、e thermometerdeviates from the reference value on two successive checks,then a full thermometer recalibration is needed.6.4.2.2 RecalibrationA complete recalibration of theliquid-in-glass thermometer, while permitted, is not necessaryin order to meet the accuracy ascribed to liquid-in-glassthermomet
27、ers design until the thermometers corrected mea-sured temperature deviates from the reference thermometer orice point by one scale division, or until five years has elapsedsince the last full calibration.6.5 Heat Source:6.5.1 Electric HeaterA hot plate or immersion heaterprovided with a variable tra
28、nsformer or other device suitablefor regulating the temperature of the heating element.6.5.2 Gas HeaterA bunsen-type burner, fitted with achimney.7. Sampling7.1 Samples from shipments shall be taken in accordancewith Practice D140 and shall be free of foreign substances.Thoroughly mix the sample bef
29、ore removing a representativeportion for the determination or for dehydration.7.2 If the presence of water is indicated by surface foam onheating, maintain the sample at a temperature of about 260 F(125 C) in an open container until the surface is free of foam.Take care not to overheat, and remove f
30、rom the heat source assoon as the foam has subsided.8. Test Specimens8.1 Coat the inner surfaces and core pins of the mold verylightly with silicone oil or silicone grease. Form the pitch intotruly shaped cubes either by pressing (8.2) or by pouring (8.4),the latter being preceded by melting (8.3) i
31、f the sample is solid.Use an excess of pitch in either case. Cool until firm andremove the surplus material by drawing the heated blade of aputty knife or spatula across the surface of the mold so that thecubes are pressed into the cavities. Then open the mold andremove the cubes carefully to avoid
32、distortion. Inspect eachspecimen for possible cracks or bubbles and reject any whichare not perfect.8.2 Pitches with softening points up to about 140 F (60 C)can usually be pressed into the mold by hand at, or slightlyabove, room temperature. If too soft, they may be pressedunder water at about 40 F
33、 (5 C).8.3 To melt a dry pitch sample, add the material to acontainer having a height equal to or exceeding its width anda volume of not less than 50 mL, until it is about half full. Placethe container on a hot plate, or in an oven or bath. Do not usean open flame for melting pitch. After melting is
34、 complete, stirgently but thoroughly, avoiding the incorporation of airbubbles. The maximum temperature should not exceed theexpected softening point by more than 90 F (50 C). Anyfoam that forms shall be skimmed off.8.4 Pour a slight excess of the liquid pitch into the moldwith the lip of the contai
35、ner close to the surface so as tominimize the entrainment of air bubbles. Underpouring pastthe blade of a spatula is helpful in this respect. Even smallbubbles markedly affect the weight of the cube and theobserved softening point. Cool the specimens in the mold untilfirm, under cold water if necess
36、ary; then trim and inspect thecubes as directed in 8.1.9. Procedure9.1 Pitches Having Softening Points Between 110 F and176 F (43 C and 80 C):D611539.1.1 Assemble the apparatus as shown in Fig. 1. Fill thecontainer to a depth of about 100 mm with freshly boileddistilled water cooled to 60 F (15 C) (
37、Notes 4 and 5). Placetwo cubes of pitch on hooks as shown in Fig. 1, warming thehooks slightly before inserting them in the center holes ifnecessary. Suspend the specimens in the bath so that the loweredges are 1 in. (25 mm) above the bottom of the container.Position the thermometer so that the bulb
38、 is between the cubesand within 6 mm, but not touching either cube. The bottom ofthe bulb should be level with the bottom of the cubes. Allowthe specimens to remain in the bath at 60 F (15 C) for 15 minbefore applying heat.NOTE 4The use of freshly boiled water is essential to prevent theformation of
39、 air bubbles on its surface which may retard the sinking of thecube.NOTE 5A sheet of filter paper that will sink when wet may be placedon the bottom of the container to prevent the pitch from sticking to theglass.9.1.2 Apply heat in such a manner that the temperature ofthe water is raised 9 F (5 C)
40、min. The rate shall be uniformand shall not be averaged over the period of the test. Themaximum permissible variation for any 1 min period, after thefirst three, shall be 61 F (0.5 C). Reject all tests in which therate of rise is outside these limits.9.1.3 The softening point is the average of the t
41、emperaturesat which the two cubes touch the bottom of the container.Estimate individual readings to the nearest 0.5 F (0.2 C).Repeat the determination if the individual values differ by morethan 2 F (1 C).9.2 Pitches Having Softening Points Below 110 F(43 C)Follow the procedures described in 9.1, bu
42、t cool thewater bath to 40 F (5 C). After immersing the specimens inthe bath, maintain the temperature for at least 15 min beforeapplying heat.10. Report10.1 Report the average value found in 9.1.3, rounded to thenearest 1 F (0.5 C) as the softening point (cube-in-water).11. Precision and Bias11.1 T
43、he following criteria shall be used for judging theacceptability of the results (95 % confidence level):11.1.1 RepeatabilityDuplicate values by the same opera-tor shall not be considered suspect unless they differ by morethan 3 F (1.5 C).11.1.2 ReproducibilityThe values reported by each of twolabora
44、tories shall not be considered suspect unless they differby more than 5 F (3 C).11.1.3 BiasThe procedure in Test Method D61 for soften-ing point has no bias because the value of softening point isdefined only in the terms of this test method.12. Keywords12.1 cube-in-water; pitch; softening pointSUMM
45、ARY OF CHANGESSubcommittee D02.05 has identified the location of selected changes to this standard since the last issue(D61 75 (2010) that may impact the use of this standard. (Approved July 1, 2015.)(1) Revised Section 2.(2) Added new Terminology Section 3.(3) Revised 6.4.ASTM International takes n
46、o position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own respon
47、sibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed
48、to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the ad
49、dress shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Dri
