1、Designation:D2234/D2234M10Standard Practice forCollection of a Gross Sample of Coal1This standard is issued under the fixed designation D2234/D2234M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number i
2、n parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONData obtained from coal samples are used in establishing price,controlling mine and cleaning plantoperations,allocating production costs,and deter
3、mining plant or component efficiency.The task ofobtaining a sample of reasonable weight to represent an entire lot presents a number of problems andemphasizes the necessity for using standard sampling procedures.Coal is one of the most difficult of materials to sample,varying in composition from non
4、combus-tible particles to those which can be burned completely,with all gradations in between.The task isfurther complicated by the use of the analytical results,the sampling equipment available,the quantityto be represented by the sample,and the degree of precision required.This practice gives the
5、overall requirements for the collection of coal samples.The wide varietiesof coal-handling facilities preclude the publication of detailed procedures for every sampling situation.The proper collection of the sample involves an understanding and consideration of the physicalcharacter of the coal,the
6、number and weight of increments,and the overall precision required.1.Scope1.1 This practice covers procedures for the collection of asample under various conditions of sampling.The sample is tobe crushed and further prepared for analysis in accordance withPractice D2013.However,the procedures for di
7、viding largesamples before any crushing are given in this practice.For thesampling of coal using mechanical sampling systems seeD7430 Practice for the Mechanical Sampling of Coal.1.2 This practice describes general and special purposesampling procedures for coals(1)by size and condition ofpreparatio
8、n(for example,mechanically cleaned coal or rawcoal)and(2)by sampling characteristics.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of
9、the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 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 and health practi
10、ces and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D2013 Practice for Preparing Coal Samples for AnalysisD7430 Practice for Mechanical Sampling of Coal3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 accuracy:3.1
11、.1.1 generallya term used to indicate the reliability of asample,a measurement,or an observation.3.1.1.2 specificallya measure of closeness of agreementbetween an experimental result and the true value.Example:the observed and true sulfur content of a coal consignment.This measure is affected by cha
12、nce errors as well as by bias.3.1.2 gross samplea sample representing one lot of coaland composed of a number of increments on which neitherreduction nor division has been performed.3.1.3 incrementa small portion of the lot collected by oneoperation of a sampling device and normally combined withoth
13、er increments from the lot to make a gross sample.1This practice is under the jurisdiction of ASTM Committee D05 on Coal andCoke and are the direct responsibility of Subcommittee D05.23 on Sampling.Current edition approved Jan.1,2010.Published February 2010.Originallyapproved in 1963.Last previous e
14、dition approved in 2009 as D2234_D2234 09a.DOI:10.1520/D2234_D2234M-10.2For 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 web
15、site.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.4 probability samplea sample collected using a sam-pling process such that at each stage of the process,a specifiednon-zero probability of being selected for the sample can beattach
16、ed to every sampling unit in the lot to be sampled.Givenadequate information about the sample results obtained usingprobability sampling,the probability distribution of samplingerrors can be estimated.3.1.5 samplea quantity of material taken from a largerquantity for the purpose of estimating properties or composi-tion of the larger quantity.3.1.6 size consistthe particle size distribution of a coal.4.Summary of Practice4.1 The general-purpose sampling procedures are intendedto provide,in 19 of