1、Designation: D6915 12D6915 17Standard Practice forCarbon BlackEvaluation of Standard Reference Blacks1This standard is issued under the fixed designation D6915; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers guidelines for the production and testing for uniformity of a set of carbon blacks to be used as StandardRe
3、ference Blacks (SRBs).1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 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
4、standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for t
5、he Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1510 Test Method for Carbon BlackIodine Adsorption NumberD2414 Test Method for Carbon BlackOil Absorptio
6、n Number (OAN)D3265 Test Method for Carbon BlackTint StrengthD3493 Test Method for Carbon BlackOil Absorption Number of Compressed Sample (COAN)D4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufacturing IndustriesD4821 Guide for Carbon BlackValidat
7、ion of Test Method Precision and BiasD6556 Test Method for Carbon BlackTotal and External Surface Area by Nitrogen AdsorptionD8043 Guide for Carbon BlackShelf Life3. Significance and Use3.1 This practice is intended to ensure that SRBs are produced and evaluated by a standard procedure.3.2 This prac
8、tice is to be used to establish the average physicochemical properties of a set of carbon blacks to be used as SRBs.3.3 The carbon black grades to be used as SRBs should be selected to give as much coverage of the typical usage range for eachtest and as nearly evenly spaced across the range as possi
9、ble. Typically, the carbon black grades selected consist of three tread(hard) type furnace grades (designated A, B, and C), three carcass (soft) type furnace grades (designated D, E, and F), and onethermal type grade (designated G). Subcommittee D24.61 may elect to carry one or more of the existing
10、SRBs into the next setprovided there is enough remaining material at the rate of usage to last through the expected life of the next set. Limiting the choiceof grades to be used means that not all tests will have an SRB set that is evenly spaced across the range of interest. All the SRBcandidates ar
11、e produced at approximately the same time by the various producers. They are used as a set once they are approved.The sets are consecutively numbered. Values and identification for the current set are given in Guide D4821. Any SRBs carriedforward will be renumbered for the new set.1 This practice is
12、 under the jurisdiction of ASTM Committee D24 on Carbon Black and is the direct responsibility of Subcommittee D24.61 on Carbon Black Samplingand Statistical Analysis.Current edition approved June 1, 2012May 1, 2017. Published August 2012May 2017. Originally approved in 2003. Last previous edition a
13、pproved in 20072012 asD6915 07.D6915 12. DOI: 10.1520/D6915-12.10.1520/D6915-17.2 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 o
14、n 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 changes accurately, ASTM recommends that user
15、s 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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Production, Packaging, Qua
16、lity Control, and Quality Assurance4.1 It is assumed that manufacturers of the SRBs will use state-of-the-art techniques to ensure maximum uniformity throughoutthe entire production run. The production should be made in one continuous production and packaging lot run. The testing calledfor in this p
17、ractice is not intended to be a substitute for in-process quality control. This interlaboratory study is only adequate toverify the quality of a homogeneous lot.4.2 The size of the lot for each SRB is determined by historical records on the rate of use. The lot should have an expected lifeof about f
18、ive years at the most recent rate of use. Historically, the lot size has usually been 10 000 lb.4.2.1 The actual usage rate of any reference material may result in one or more SRB material being depleted before theremaining materials in a given SRB set. When this happens, Subcommittee D24.61 may ele
19、ct to have a supplemental lot producedfor the needed SRB(s).4.2.2 It is preferred that any supplemental SRB lots be produced at the same location, on the same production equipment, underthe same production conditions as reasonably possible, and using the same production targets and specifications as
20、 was used toproduce the initial SRB lot in order to minimize variation between the two lots.4.2.3 The supplemental lot size must be large enough to meet the expected life of the remaining materials in the SRB set andwithout a prohibitively large quantity remaining for disposal after the remainder of
21、 the set is depleted. Multiples of typical palletquantities of 1134 kg (2500 lb) are preferred. The total quantity produced must be enough to meet the needed supplemental lotsize and have sufficient material to flush the packaging equipment as described in 5.4.4.2.4 The supplemental SRB lot shall ca
22、rry the same reference designation as the SRB material it is replacing with the additionof another digit numbering the lot, beginning with the digit “2”. For example, a supplemental lot for the reference material SRB8Awould be designated SRB8A2. If the conditions of 4.2.3 are met, there will not be
23、a need for another supplemental lot of any givenSRB material.4.3 The SRB material should be bagged in 22.7 kg (50-lb) polyethylene bags to reduce moisture incursion. Each pallet shouldhave a nominal 50 bags. Each pallet of bagged material should be wrapped in plastic to reduce environmental exposure
24、.5. Uniformity Sampling and Testing5.1 It is the producers responsibility to ensure the SRB is produced under stable conditions using good statistical processcontrol techniques. Such control techniques include but are not limited to:5.1.1 Stable statistical process control for at least 24 h prior to
25、 isolating the candidate SRB material.5.1.2 Stable statistical process control during the entire period the candidate SRB material is being produced. If there is anoccurrence of instability (process not in statistical control) while the candidate SRB material is being produced, the isolatedmaterial
26、must be discarded and a new period of stability demonstrated per 5.1.1.5.1.3 The storage vessel used to hold the candidate SRB material must be emptied and reasonably cleaned prior to being usedto isolate the candidate SRB material. The emptying and cleaning is particularly important if the storage
27、previously held a materialof a different grade than the candidate SRB material.5.2 The producer shall maintain all test equipment in proper calibration and be able to supply proof of calibration records, ifrequested. It is preferred that the testing laboratory for the production facility be an activ
28、e participant in D24s LaboratoryProficiency Rating System (LPRS) program. Active participation shall be demonstrated by submitting test results for at least theprevious three LPRS samples.5.3 The producer of the SRB shall be responsible for performing all testing to demonstrate lot uniformity, and t
29、he producer mustsubmit the uniformity data to subcommittee D24.61. The tests to be performed as a minimum are those listed in Section 6.All testresults must be 62 repeatability standard deviations as determined for each test using any one of the following means ofdetermining Sr:(1) Any appropriate S
30、RB materials Sr listed in the precision table for a given test.(2) The average pooled value Sr listed in the precision table for a given test.(3) Determine a tests Sr using a linear regression from existing precision data for a given test as defined in Annex A1.5.4 The packaging equipment used to pa
31、ckage the SRB lot must be flushed to remove any possible contamination from othermaterials that may remain in the packaging system. This flushing shall be accomplished by packaging at least 10 000 kg (22 000lb) of the SRB material before isolating the packages to be used for the SRB lot. This flushi
32、ng is especially critical if the samepackaging equipment is used to package other grades of carbon black.5.5 The samples for determining lot uniformity shall be taken at the same time as when the SRB is packaged. The number ofsamples and sampling location needed to demonstrate uniformity shall be:5.
33、5.1 Typically a bag is removed from the packaging stream at the designated sample location without reducing the total bagcount on the pallet (nominally 50) so that the total number of bags pulled is the sum of bags on the pallet and bags needed forsamples. It may be necessary to remove more than one
34、 bag at each sampling event to provide a sufficient quantity for subsequentuniformity testing per 5.6.D6915 1725.5.2 If just one pallet of material is being packaged, take a sample at the beginning (bottom layer), middle, and end (top layer)of the pallet.5.5.3 If more than one pallet of material is
35、being packaged, take a sample at the beginning (bottom layer) and middle of eachpallet and the end (top layer) of the last pallet.5.6 The number of samples taken and the quantity collected for each sample shall be adequate to perform all uniformity testingand have sufficient material, such that when
36、 all sample material is combined and blended, there will be enough material that allthe laboratories participating in the determination of the mean and control limit testing can perform the test protocol and havematerial left if additional testing is subsequently needed.6. Procedure6.1 Each laborato
37、ry will use the current SRBs to verify that all test methods are in calibration.6.2 Each sample is tested once on each of two days by two different technicians (total of four test results).6.3 Physicochemical Tests:6.3.1 Perform the following physicochemical tests on the new SRB (this does not apply
38、 to the testing of the Heat Treated (HT)SRBs):6.3.1.1 Iodine Adsorption Number (Test Method D1510)Report the result obtained from an individual determination in gramsof iodine per kilogram to the nearest 0.1 unit.6.3.1.2 Multipoint B.E.T. NSA (Test Method D6556)Report a single determination in 103 m
39、2/kg (m2/g) to the nearest 0.1 unit.6.3.1.3 Oil Absorption Number (Test Method D2414)Report the result obtained from an individual determination in 10-5m3/kg (cm3/100 g) to the nearest 0.1 unit.NOTE 1Each participating laboratory must ensure that the absorptometer has been properly calibrated. Repor
40、ted OAN values must be regressed tothe previous SRB set.6.3.1.4 Oil Absorption Number of Compressed Sample (Test Method D3493)Report the result obtained from an individualdetermination in 10-5 m3/kg (cm3/100 g) to the nearest 0.1 unit.NOTE 2Each participating laboratory must ensure that the absorpto
41、meter has been properly calibrated. Reported COAN values must be regressed tothe previous SRB set.6.3.1.5 Tint Strength (Test Method D3265)Report the result obtained from an individual determination in percent of ITRB tothe nearest 0.1 unit.6.3.1.6 Statistical Thickness Surface Area (STSA) (Test Met
42、hod D6556)Report single determination in 103 m2/kg (m2/g) to thenearest 0.1 unit.6.4 For the HT SRBs, perform the Iodine Adsorption Number Test (Test Method D1510). Report the result obtained from anindividual determination in grams of iodine per kilogram to the nearest 0.1 unit.7. Statistical Analy
43、sis7.1 The uniformity sample material collected by the producer shall be blended, apportioned, and sent to each participant in theinterlaboratory study to evaluate the new SRB.7.2 To achieve statistical validity and allow for the removal of outliers, at least 20 laboratories should participate in th
44、eevaluation for each test method.7.3 Each participating laboratory shall maintain all test equipment in proper calibration and be able to supply proof ofcalibration and calibration records, if requested.7.4 The interlaboratory study protocol shall be determined by subcommittee D24.61 prior to the pr
45、oduction of the SRB(s).7.5 The mean and control limit values of the SRBs for each test shall be determined using the methodology of Practice D4483,including the removal of outlier values.7.6 When calibration data is collected along with the test results for a new SRB and an analysis of the calibrati
46、on data showsthat any given laboratory is not in a state of calibration, the data from that laboratory may be removed from the data set even thoughthe data is not flagged as being an outlier by the techniques of Practice D4483.7.7 After eliminating the outliers and any laboratories not in a state of
47、 calibration, the remaining data for each test method willbe used to provide mean and control limit values for tabulation in Guide D4821. This information may also be placed in each testmethod, if desired. The analysis could be used to develop new precision and bias values for each test method.8. Ac
48、ceptance8.1 Subcommittee D24.61 may reject all or part of a candidate SRB lot as not uniform. All SRB lots tested as homogeneousby this practice will be considered acceptable by Committee D24 for use as a new SRB. The mean values and control limits willbe published in Guide D4821.D6915 1739. Shelf L
49、ife9.1 The shelf life of the Standard Reference Black (SRB) carbon blacks is indefinite when properly stored in a manner thatprotects it from exposure to sources of moisture, such as precipitation, other sources of liquid water, or high humidityenvironments. Iodine number is the only property known to change over an extended period (years). This is due to a slow increasein the oxygen content and is primarily observed with tread blacks and other high surface area carbon blacks. Steps are being takenwithin ASTM Committee D24 to develop standards that are more
