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ASTM_D_2449_-_88_2015.pdf

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1、Designation:D244988(Reapproved 2015)Standard Specification forRubber Bales From Natural SourcesLimit on Coating1This standard is issued under the fixed designation D2449;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of las

2、t revision.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 specification covers bale coating on bales of naturalrubber(that have rubber wrapper sheets on the bales)andincludes test

3、 method description.It specifies the maximumpermissible amount of such coating.1.2 This specification is not applicable to natural rubber thatis packaged with plastic wrappers,as no bale coating is used.1.3 The following safety hazards caveat pertains only to thetest method portion,Section 5,of this

4、 specification:Thisstandard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.2.Referen

5、ced Documents2.1 ASTM Standards:2D1278 Test Methods for Rubber from Natural SourcesChemical AnalysisD1485 Practice for Rubber from Natural SourcesSampling and Sample Preparation3.Requirements3.1 The average amount of bale coating on the bales in thesample should not exceed 4 6 0.1 g/kg of rubber.Lot

6、s may berejected if the bale coating exceeds this amount.NOTE1Four grams per kilogram of rubber is equivalent to amaximum of 1 lb/250 lb-bale.4.Sampling4.1 Carefully remove portions at random from the outsidewrapper sheets from any three sides of the bale so as to lose aminimum of bale coating.Handl

7、e and store the sampledportions so as to lose a minimum of bale coating.The numberof bales sampled from a lot shall be in accordance with PracticeD1485,or as agreed upon between the purchaser and the seller.5.Test Methods5.1 Summary of Methods:5.1.1 Method AThe amount of mineral filler from balecoat

8、ing present on the outside wrapper sheets of the bales isdetermined using an ashing procedure.5.1.2 Method BThe amount of bale coating on the outsidewrapper sheets of all grades of smoked sheet rubbers only isdetermined by a brushing or scraping procedure.5.1.3 The brushing or scraping procedure,whi

9、le muchfaster,is not suitable for use on crepe sheet rubbers because ofpenetration through holes in the outside wrapper sheet anddifficulties of removal from between wrapper sheets.Thisnecessitates the use of the ash procedure on crepe sheetrubbers.5.2 Significance and UseThe rubber bale coating is

10、usefulfor eliminating the adhesion or sticking together of bales whenin contact with each other during transportation and/or storage.Excessive coating may result in reduced compounded physicalproperties.5.3 Procedure:5.3.1 Method A(Ash Method)Die out or cut two 50 by50-mm test specimens,within a tol

11、erance of 61 mm,fromeach of three portions removed from the bale,taking care notto lose the bale coating.Test each specimen separately.Anybale coating falling from the test specimen should be added tothe ash crucible together with the test specimen.Ash inaccordance with Test Methods D1278,with the e

12、xception ofthe weight of the 50-mm square specimen to the nearest 0.01 grather than a 5 to 6-g specimen of homogenized rubber.5.3.2 Method B(Brushing or Scraping Method)Die out orcut out a test specimen 150 by 150-mm,within a tolerance of61 mm,from each of the three portions removed from thebale,fol

13、lowing the precautions given in 4.1.Weigh the testspecimen to the nearest 0.01 g before and after removal of balecoating.Remove the bale coating,using a stiff wire brush or byscraping,taking care not to abrade rubber from the wrappersheet while thoroughly removing as much of the bale coatingas possi

14、ble.5.4 Calculations:1This specification is under the jurisdiction ofASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.22 on Natural Rubber.Current edition approved Sept.1,2015.Published December 2015.Originallyapproved in 1965.Last previous edition approved in 2011 as

15、 D2449 88(2011).DOI:10.1520/D2449-88R15.2For 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 page onthe ASTM website.Copyright ASTM Internation

16、al,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.4.1 Method A(Ash Method)Calculate the amount ofbale coating per bale as follows:A 5 BC/SW(1)where:A=amount of bale coating,g/kg rubber,B=nominal surface area of bale,mm2,C=average amount of ash for the six test specimens,g,S=surface area of test specimen,mm2,andW=nominal weight of bale,kg.5.4.2 Method B(Brushing or Scraping Method)Calculatethe amount of bale coating per bale as follows:A 5 BC/SW(2)where:A=amoun

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