1、Designation:D429618Standard Practice forSampling Pitch1This standard is issued under the fixed designation D4296;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 parentheses indicates the year of
2、last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers procedures for sampling pitch atpoints of manufacture,storage,and delivery.1.2 The values stated in SI units are to be regarded asstandard.The values in parenthe
3、ses are for information only.1.3 This standard does 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,health,and environmental practices and deter-mine the applicability of regulatory
4、limitations prior to use.Specific warning statements are given in Section 11.1.4 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
5、Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 bulk sample,na large sample,either from one placeor made up of several incremental samples of the samematerial.2.1.2 composite sample
6、,na thoroughly mixed grosssample.2.1.3 gross sample,na large sample made up of severalportions(increments)of a mass of material.2.1.4 increment,na portion of a material to be combinedwith other portions of the same material to provide a largersample which will represent the whole material.2.1.5 repr
7、esentative sample,na part of a homogeneousmaterial,or a part of the composited and mixed portions of amaterial,which carries all the true properties and physicalcharacteristics of the whole material.2.1.6 sample,na part taken as representative of a wholematerial.3.Summary of Practice3.1 Samples of l
8、iquid pitches are taken from process lines,storage,and shipment containers in increments required toprepare a representative sample for testing.3.2 Samples of solid pitches are taken from loadingsystems,storage,and shipment containers in increments re-quired to prepare a representative sample for te
9、sting.4.Significance and Use4.1 Sampling is as important as testing.If the sampling isimproperly done,the sample of the material will be in error,and the analysis will not represent the true properties of thematerial,and it may be impossible or impracticable to takeanother sample;whereas,if the samp
10、le is properly taken andthe analysis is in error,another analysis can readily be made ofthe original sample.4.2 Samples may be taken for either of the following twopurposes:4.2.1 To represent as nearly as possible an average of thebulk of the materials sampled,or4.2.2 To ascertain the maximum variat
11、ion in characteristicswhich the material possesses.4.3 A good sampling plan has the following characteristics:4.3.1 It protects the consumer against the acceptance of abad batch of material.4.3.2 It protects the producer against the rejection of a goodbatch of material.4.3.3 It gives long-range prot
12、ection to the consumer.4.3.4 It encourages the producer to keep his process incontrol.4.3.5 It minimizes the cost of sampling,inspection oftesting,and administration.4.3.6 It provides information concerning the quality of theproduct.4.4 Sampling IntegrityWhen one takes a sample,one isattempting to r
13、epresent a batch or lot of material with thatsample.Different forms of pitch,and pitch in different types ofcontainers,need to have different sampling plans and appro-priate sampling equipment.Each sampling plan should bedesigned so that it accomplishes its objective,which is toascertain the charact
14、eristics or quality of a batch or lot ofmaterial.1This practice is under the jurisdiction of ASTM Committee D02 on PetroleumProducts,Liquid Fuels,and Lubricants and is the direct responsibility of Subcom-mittee D02.05 on Properties of Fuels,Petroleum Coke and Carbon Material.Current edition approved
15、 Dec.1,2018.Published December 2018.Originallyapproved in 1983.Last previous edition approved in 2015 as D4296 83(2015)1.DOI:10.1520/D4296-18.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-295
16、9.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 Technical Barriers to Trade(TBT)Committee.1 5.Selection of Samples5.1 Pitches shall be sampled by the producer at the point ofmanufacture or storage,and at such time as to allow the testscontrolling acceptance or