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ASTM_D_2449_-_88_2020.pdf

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1、Designation:D244988(Reapproved 2020)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,health,andenvironmental practices and determine the applicability ofregulatory limitations prior to u

5、se.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers

6、to Trade(TBT)Committee.2.Referenced 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 e

7、xceed 4 6 0.1 g/kg of rubber.Lots 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 los

8、e aminimum of bale coating.Handle 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

9、 of mineral filler from balecoating 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 br

10、ushing or scraping procedure,while 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 an

11、d UseThe rubber bale coating is 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 by5

12、0-mm test specimens,within a tolerance 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 wi

13、th Test Methods D1278,with the exception 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 p

14、ortions removed from thebale,following the precautions given in 4.1.Weigh the testspecimen to the nearest 0.01 g before and after removal of bale1This specification is under the jurisdiction ofASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.

15、22on Natural Rubber.Current edition approved June 1,2020.Published July 2020.Originally approvedin 1965.Last previous edition approved in 2015 as D2449 88(2015).DOI:10.1520/D2449-88R20.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.o

16、rg.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization T

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