1、Designation: D1937 12Standard Test Method forCarbon Black, PelletedMass Strength1This standard is issued under the fixed designation D1937; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the massstrength of pelleted carbon black. It is designed to determinethe force required to pack a cylin
3、drical column with pelletedcarbon black. The results of this test are believed to relate to theability of the carbon black to flow in bulk handling systems.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard d
4、oes not purport 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 St
5、andards:2D1799 Practice for Carbon BlackSampling PackagedShipmentsD1900 Practice for Carbon BlackSampling Bulk Ship-mentsD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries3. Summary of Test Method3.1 A sample of carbon black is pla
6、ced in a vertical cylinderand pressed with a plunger for 10 s after which the bottom ofthe cylinder is opened, whereupon all of the carbon black eitherfalls out the bottom or forms a ring or bridge in the cylinder.The process is repeated with a new sample until the minimumforce required for the carb
7、on black to form a ring or bridge isfound. The resultant force is called mass strength and isreported in Newtons (lbf).4. Significance and Use4.1 Mass strength gives an indication of the flowability inbulk handling. It is affected by pellet properties such ashardness, size, shape, and especially fin
8、es content. Due to theinfluence of other variables, the user and the producer mustdetermine an acceptable mass strength level.5. Apparatus5.1 Mass Strength Tester,3with a flat compression cylinderof 50.8 mm (2 in.) diameter.5.2 Calibrating Block, made from a cylindrical woodenshaft, 47 mm (1.8 in.)
9、in diameter and 250 mm (10 in.) long.5.3 Platform Scale,4to 50-kg (100 lb) capacity with asensitivity of 0.1 kg (0.02 lb) for air pressure gage calibration.5.4 Overflow Cup to Fit Around Cylinder, normally part ofthe apparatus delivery.5.5 Spatula, with a straight edge of at least 55 mm (2.2 in.).6.
10、 Sampling6.1 Samples shall be taken in accordance with PracticesD1799 or D1900.7. Calibration7.1 Remove the original faceplate from the pressure gageand replace with a blank plate made from aluminum or othersuitable material.7.2 Place the platform scale under the cylinder. With thesliding door in an
11、 open position, pass the calibrating blockthrough the cylinder so it will rest on the platform of theplatform scale. The top of the calibrating block shall be nearthe cylinder top. The calibrating block must fit freely in thecylinder and not bind against any inside surface. Adjust theplatform scale
12、for zero position with the calibrating block inplace. Mark the zero position on the blank plate.1This test method is under the jurisdiction of ASTM Committee D24 on CarbonBlack and is the direct responsibility of Subcommittee D24.51 on Carbon BlackPellet Properties.Current edition approved June 1, 2
13、012. Published August 2012. Originallyapproved in 1962. Last previous edition approved in 2010 as D1937 10. DOI:10.1520/D1937-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informati
14、on, refer to the standards Document Summary page onthe ASTM website.3The sole source of supply of the mass strength tester known to the committeeat this time is Titan Specialties, Inc., P.O. Box 2316, Pampa, TX 79066-2316. TestMethod D1937 84 contains details for the construction of this apparatus.
15、If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.4AFairbanks Morse platform scale, Model 411000 (beam suffix FM) is
16、suitablefor this purpose.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States17.3 Adjust the air-flow regulator until the needle on the airpressure gage has moved from rest or zero position, toone-third or more of total gage capacity.7.4 A
17、ctivate the timer, allowing the plunger to press againstthe calibrating block. Measure the equivalent mass producedby the plunger with the platform scale.7.5 Repeat 7.4, adjusting the regulator until even multiplesof 50 N or 10 lbf are obtained. Mark the plate at these values.7.6 Between each 50 N o
18、r 10 lbf mark on the plate, placegraduations representing each 10 N or 2 lbf. This may be donefrom measurement, since the gage should be linear in calibra-tion. Check these marks for accuracy with the platform scale.7.7 From this calibrated gage plate, another gage plate maybe prepared by making the
19、 graduations coincide with thosemeasured on the calibrated plate. All graduations shall bechecked with the platform scale for accuracy.7.8 The calibrated air pressure gage shall be recalibrated atleast once a month, or more frequently as deemed necessary.8. Procedure8.1 Clean the cylinder with a bru
20、sh to remove any adheringcarbon black. With the sliding door closed and the overflowcup in position, pour carbon black pellets into the cylinder untilan excess of pellets forms a cone above the rim. Level thesurface with a single sweep of a straightedge or spatula heldperpendicular to, and in firm c
21、ontact with the top of thecylinder. The top surface of the carbon black column shall belevel to prevent unequal pressure on the column.8.2 Select the force to be applied by adjusting the air-flowregulator until the calibrated gage indicates the desired value.The setting for the initial press is disc
22、retionary and is basedusually on lab experience.NOTE 1Soft pellets with irregular shape and high fines tend to havelow mass strength. For these materials an initial setting of 100 N or 20 lbfis suggested. More spherical pellets with higher pellet hardness and lowfines tend to have high mass strength
23、. For these materials an initial settingof 250 N or 50 lbf is suggested.8.3 Press the timer switch activating the mechanism, allow-ing air flow to the air cylinder. The timer shall be set to allowa total plunger application time of 10 s on the sample.8.4 After the plunger returns to the rest positio
24、n above thesample, open the sliding door and observe the inside of thecylinder. If no black remains in the cylinder, the end point hasnot been reached. The test is then repeated on untested portionsof the sample using successively higher pressures following thetest sequence in 8.1-8.4NOTE 2The incre
25、ments of increased force are discretionary. Steps of50 or 100 N (10 or 20 lbf) are appropriate.8.5 Once a bridge of pressed carbon black is formed, the endpoint has been reached or exceeded. An additional test shouldbe performed at a lower pressure to confirm the end point hasnot been exceeded. The
26、end point is the lowest number ofnewtons (pounds-force) required to produce a ring or bridge ofpressed carbon black in the cylinder.9. Report9.1 Report the following information:9.1.1 Proper identification of the sample and,9.1.2 Result obtained from an individual determinationreported to the neares
27、t 25 N (5 lbf).10. Precision and Bias10.1 These precision statements have been prepared inaccordance with Practice D4483. Refer to this practice forterminology and other statistical details.10.2 The precision results in this precision and bias sectiongive an estimate of the precision of this test me
28、thod with thematerials used in the particular interlaboratory program de-scribed below. The precision parameters should not be used foracceptance or rejection testing of any group of materialswithout documentation that they are applicable to those par-ticular materials and the specific testing proto
29、cols of the testmethod. Any appropriate value may be used from Table 1.10.3 A type 1 inter-laboratory precision program was con-ducted as detailed in Table 1. Both repeatability and reproduc-ibility represent short-term (daily) testing conditions. Thetesting was performed using two operators in each
30、 laboratoryperforming the test once on each material on each of two days(total of four tests).TABLE 1 Precision Parameters for ASTM D1937, Carbon Black, PelletedMass Strength (Type 1 Precision)NOTEUNITS =N(LBF)MATERIAL PERIOD NUMBER OF LABORATORIES MEAN LEVEL SRRSR RLS CARCASS SPRING 2004 30 4.4(9.6
31、)0.39(0.86)1.10(2.43)2.52(5.54)7.13(15.68)N774 FALL 2002 17 6.4(14.0)0.51(1.12)1.44(3.17)4.04(8.89)11.44(25.16)HS TREAD FALL 2003 30 10.5(23.0)0.66(1.46)1.87(4.12)5.63(12.40)15.95(35.10)SRB C6 (N326) SPRING 2003 29 10.6(23.3)0.70(1.54)1.98(4.36)4.71(10.37)13.34(29.34)SRB A6 (N134) FALL 2004 37 36.9(
32、81.2)1.05(2.32)2.98(6.56)3.37(7.42)9.55(21.00)AVERAGE 13.7(30.2)POOLED VALUES 0.70(1.54)2.00(4.36)4.20(9.23)11.88(26.13)D1937 12210.4 The results of the precision calculations for this test aregiven in Table 1. The materials are arranged in ascending“mean level” order.10.5 RepeatabilityThe pooled ab
33、solute repeatability, r,ofthis test has been established as 2.00 N (4.36 lbf). Any othervalue in Table 1 may be used as an estimate of repeatability, asappropriate. The difference between two single test results (ordeterminations) found on identical test material under therepeatability conditions pr
34、escribed for this test will exceed therepeatability on an average of not more than once in 20 casesin the normal and correct operation of the method. Two singletest results that differ by more than the appropriate value fromTable 1 must be suspected of being from different populationsand some approp
35、riate action taken.NOTE 3Appropriate action may be an investigation of the test methodprocedure or apparatus for faulty operation or the declaration of asignificant difference in the two materials, samples, and so forth, whichgenerated the two test results.10.6 ReproducibilityThe pooled absolute rep
36、roducibility,R, of this test has been established as 11.88 N (26.13 lbf). Anyother value in Table 1 may be used as an estimate ofreproducibility, as appropriate. The difference between twosingle and independent test results found by two operatorsworking under the prescribed reproducibility condition
37、s indifferent laboratories on identical test material will exceed thereproducibility on an average of not more than once in 20 casesin the normal and correct operation of the method. Two singletest results produced in different laboratories that differ bymore than the appropriate value from Table 1
38、must besuspected of being from different populations and some appro-priate investigative or technical/commercial action taken.10.7 BiasIn test method terminology, bias is the differencebetween an average test value and the reference (true) testproperty value. Reference values do not exist for this t
39、estmethod since the value or level of the test property isexclusively defined by the test method. Bias, therefore, cannotbe determined.11. Keywords11.1 bulk handling systems; carbon black; flow in bulkhandling systems; mass strength; pelleted carbon blackASTM International takes no position respecti
40、ng 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 responsibility.This stand
41、ard 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 to ASTM Internation
42、al 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 address shown below.T
43、his 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 ASTM website (www.astm.org/COPYRIGHT/).D1937 123
