1、Designation:D 4702 07Standard Practice forQuality Management of Mechanical Coal Sampling Systems1This standard is issued under the fixed designation D 4702;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A n
2、umber 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 is applicable to cross-belt,falling-stream,and auger sampling systems.1.2 Spacing of increments pertains to the kind of interv
3、albetween increments.Intervals can be defined in quantitativeterms,such as units of time or mass,or in terms of positionover the lot.1.2.1 Spacing of Increments for Cross-Belt and Falling-Stream SamplersCross-belt and falling-stream type me-chanical sampling systems take increments based on time,eit
4、her at fixed time intervals or at random times during a fixedtime strata.Some falling-stream samplers can take incrementsbased on equal mass of coal sampled as determined by scales.The sections of this practice that pertain to cross-belt andfalling-stream samplers describe procedures for only time-b
5、ased sampling systems.This time-based inspection guidelinewill satisfy most criteria for mass-based or combinationmass-based and time-based sampling systems.If there areitems that are not covered,the inspector should refer to themanufacturers literature.1.2.2 Spacing of Increments for Auger Sampling
6、Thespacing of increments collected by auger sampling systems isdefined in terms of position over the lot.1.3 It is essential that the inspector have the documentationlisted in Section 2 of this practice when conducting aninspection.1.4 The values stated in SI units are to be regarded as thestandard.
7、The values given in parentheses are for informationonly.1.5 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 practices and determine the applica-bility o
8、f regulatory limitations prior to use.For a specifichazard statement,see Section 5.2.Referenced Documents2.1 ASTM Standards:2D 121 Terminology of Coal and CokeD 2013 Practice for Preparing Coal Samples for AnalysisD 4749 Test Method for Performing the Sieve Analysis ofCoal and Designating Coal SizeD
9、 4916 Practice for Mechanical Auger SamplingD 7256/D 7256M Practice for Mechanical Collection andWithin-System Preparation of a Gross Sample of Coalfrom Moving Streams3.Terminology3.1 DefinitionsDefinitions applicable to this practice arelisted in Terminology D 121 and Practices D 2013,D 7256/D 7256
10、M and D 4916.4.Significance and Use4.1 This practice addresses quality assurance criteria foroperation of a mechanical coal-sampling system in accordancewith Practice D 7256/D 7256M,Practice D 2013,and PracticeD 4916.It provides recommendations for performance moni-toring,inspection,and maintenance,
11、which are necessary inmaintaining a sampling systems capability to consistentlyobtain a representative sample.5.Hazards5.1 PrecautionsIn addition to other precautions,person-nel visiting facilities for observation of mechanical samplingsystem performance should immediately upon arrival report tothe
12、facility management to inform them of their presence andthe purpose of their visit.The inspector should ask for1This practice is under the jurisdiction of ASTM Committee D05 on Coal andCoke and is the direct responsibility of Subcommittee D05.23 on Sampling.Current edition approved May 1,2007.Publis
13、hed May 2007.Originallyapproved in 1987.Last previous edition approved in 2006 as D 4702 06.2For 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 Summar
14、y page onthe ASTM website.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.NOTICE:This standard has either been superseded and replaced by a new version or withdrawn.Contact ASTM International(www.astm.org)for the latest informationdrawing
15、s,specifications,and instructions on the applicablesafety practices and regulations to be followed on the site.6.Assessing the Organization and Planning of SamplingOperations6.1 It is recommended that inspection personnel meet withthe appropriate personnel responsible for the mechanical sam-pling sy
16、stem,on all visits,to discuss the organization andplanning of sampling operations.ASTM standards provide forthe use of various options.Examples and references are givenin 6.1.1 and 6.1.2 as follows:6.1.1 Cross-Belt and Falling-Stream SamplersThe num-ber of primary increments for the gross sample collected bycross-belt and falling-stream systems can be determined fromsections 8.1.1.4 and 8.1.1.5 of Practice D 7256/D 7256M.6.1.2 Auger SamplingConsiderations for the number ofauger increments per lo