1、Designation: D 4749 87 (Reapproved 2007)Standard Test Method forPerforming the Sieve Analysis of Coal and Designating CoalSize1This standard is issued under the fixed designation D 4749; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method cov
3、ers procedures for determining thesieve analysis of coal and designating the size of coal fromsieve analysis data. Raw as well as prepared (crushed, cleanedor screened) coals can be tested by this test method.1.2 This test method explains how to designate coal sizesfrom the results of sieve analysis
4、 data in order to represent thecondition of the coal as sold. In the case of special mixtures orcoals with noncontinuous ranges of sizes, a sufficiently com-plete sieve analysis must be made to properly describe the sizedistribution.1.3 This test method is not applicable for determining thesieve ana
5、lysis nor for designating the size of pulverized coal.(See Note 1.) Size fractions down to and including 38 m (No.400 U.S.A. Standard Series) can be treated by the methodsdiscussed in this test method. Methods for handling sizefractions below 38 m (No. 400) will be developed by thiscommittee.NOTE 1F
6、or powdered or pulverized coal as is fired into steam boilers,refer to Test Method D 197.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly. The values stated in each system may not be exactequivalents; therefore, each system
7、must be used indepen-dently of the other, without combining values in any way.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 deter
8、mine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 197 Test Method for Sampling and Fineness Test ofPulverized CoalD 346 Practice for Collection and Preparation of CokeSamples for Laboratory AnalysisD 388 Classification of Coals by RankD 2013
9、Practice for Preparing Coal Samples for AnalysisD 2234/D 2234M Practice for Collection of a Gross Sampleof CoalD 3302 Test Method for Total Moisture in CoalD 4371 Test Method for Determining the Washability Char-acteristics of CoalE11 Specification for Wire Cloth and Sieves for TestingPurposesE 323
10、Specification for Perforated-Plate Sieves for TestingPurposes2.2 Other Document:Specification C-80 Commonwealth of Pennsylvania, De-partment of General Services, Bureau of Purchases, Speci-fication for Coal:Anthracite33. Descriptions of Terms Specific to this Standard3.1 as-mined coalsame as ROM coa
11、l (3.8).3.2 as-shipped or produced coalraw or prepared coal inany state or condition at which it leaves the mine property orloading facility.3.3 bottomsize, nominalthe sieve designating the lowerlimit or bottomsize shall be that sieve of the series given inSection 6 with the largest openings through
12、 which passes atotal of less than 15 % of the sample. This defined bottomsizeis not to be confused with the size of the smallest particles inthe lot. (WarningIn the case of a commercial, double-screened product, for example, 37.5 by 9.5 mm (112 by38 in.),1This test method is under the jurisdiction o
13、f ASTM Committee D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.07 on PhysicalCharacteristics of Coal.Current edition approved Oct. 1, 2007. Published October 2007. Originallyapproved in 1987. Last previous edition approved in 2002 as D 474987 (2002)e1.2For referenced ASTM
14、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.3Available from Commonwealth of Pennsylvania, Dept. of General Services,Bureau of
15、Purchases, 414 N. Office Building, Harrisburg, PA 17125.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.this designation may not be valid. In such commercial orcontractual situations, the amount of allowable materialsmaller than the
16、bottomsize (for example, 9.5 mm) must bespecified by the contract under which the coal is bought andsold.)3.4 dry sievingfor the purposes of this test method, thetest method for the sieving of coal after the sample has beenair-dried under prescribed conditions; this is generally usedwhen testing wit
17、h coal particles larger than 600 m. (No. 30U.S.A. Standard Sieve Series.)3.5 openingfor the purpose of this test method, openingsand apertures shall be regarded as synonomous terms. Dimen-sions for round and square openings shall be determined asfollows: for round holes, dimensions shall refer to th
18、e openingdiameter; for square holes, dimensions shall refer to thedistance between parallel wires.3.6 prepared coalany coal, regardless of its topsize, thathas been manually or mechanically cleaned. This includes coalthat has been processed over a picking table or air tables,through a breaker, jig,
19、or other device which segregatesaccording to size or density (specific gravity).3.7 raw coalany coal, regardless of its topsize, that hasnot been manually or mechanically cleaned. Crushed coal thathas not been mechanically cleaned (including coal that has notbeen through a breaker which normally rej
20、ects oversize) isconsidered to be raw coal. Coal delivered to the surface froman underground mine is considered to be raw coal even whencrushing and grinding is done underground. Coal removedfrom the pit of a surface mine is considered to be raw coal evenwhen breaking and crushing facilities are pro
21、vided in the pit.3.8 run-of-mine (ROM) coalin the case of an undergroundmine, it is that coal delivered to the surface by a slope belt,hoist, etc. In the case of a surface mine, it is that coal as it existsafter it has been removed from the pit and placed into the initialmeans of transportation whet
22、her it be an on-the-road oroff-the-road haul truck, dump hopper which feeds a pit-to-plantconveyor, etc. For both underground and surface mines, ROMcoal is as-mined and has not been exposed to any treatmentsuch as breaking, crushing, or cleaning except for that done bythe normal operations used to e
23、xtract the coal from the ground,that is, blasting, ripping, loading, cutting, etc.3.9 topsize, nominalthe sieve designating the upper limitor topsize shall be that sieve of the series given in Section 6with the smallest openings upon which is cumulatively retaineda total of less than 5 % of the samp
24、le. This defined topsize isnot to be confused with the size of the largest particle in the lot.3.10 wet sievingfor the purposes of this test method, thetest method for the sieving of coal that uses water as a mediumfor facilitating the segregation of the sample into particle sizes;this is generally
25、used when testing coal particles 600 m (No.30 U.S.A. Standard Series) or smaller.4. Significance and Use4.1 This test method concerns the sieving of coal intodesignated size fractions for the purpose of characterizing thematerial as to its particle size distribution for further processingor for comm
26、ercial purposes. This is covered in Part A of thisstandard. Raw, as well as prepared (crushed, cleaned, orscreened), coals can be tested by this test method.4.2 This test method is applicable for all types of coals,except for pulverized coals (see Method D 197) such as fedinto steam boilers. Low ran
27、k coals, that is, lignites, subbitu-minous, and high volatile bituminous C, must be dried withcaution and handled with care to minimize deterioration or sizedegradation during sieving.4.3 This test method is applicable for the wet or dry-sievingof coal at sizes from 200 mm (8 in.) to 38 m (No. 400 U
28、.S.A.Standard). Methods for sizing materials below 38 m areoutside the scope of this test method.NOTE 2The sizing of material that passes the 38 m sieve is normallyperformed by optical microscopy, sedimentation, centrifugation, lightscattering or obfuscation, surface area measurement, or other suchm
29、ethods. Subsieve techniques are also used sometimes.4.4 This test method also concerns the designation of a coalsample as to its upper (nominal top-size) and lower (nominalbottom-size) limiting sizes for the purpose of characterizing thematerial for further processing or for commercial purposes.This
30、 is covered in Part B of this test method.Anthracite coal isfurther designated by a one word descriptive term (see 14.4).4.5 Enough material may not be collected by this testmethod to meet subsequent test procedures, such as washabil-ity analyses (Test Method D 4371).PART A. SIEVE ANALYSIS OF COAL5.
31、 Apparatus5.1 Sieves:5.1.1 Wire Cloth Sieves:5.1.1.1 Standard test sieves that conform to SpecificationE11shall always be used.5.1.1.2 For most sieve tests, where the largest particle in thesample does not exceed 25 mm (1 in.), standard 203-mm(8-in.) diameter, 50-mm (2-in.) deep sieves or sieves wit
32、hlarger diameters (for example 300 mm (12 in.) or 450 mm (18in.) are recommended. For special cases, and with smallsamples, 75-mm (3-in.) and 150-mm (6-in.) diameter sieves areavailable.5.1.1.3 Standard test sieves shall be made from either brassor stainless steel frames and either brass, phosphor b
33、ronze, orstainless steel cloth.5.1.1.4 In general, these square mesh sieves are used whensizing with sieves with openings smaller than 6.3 mm (14 in.).U.S.A. Standard Sieve Designations shall be used.5.1.1.5 For more complete details of standard test sieves,including methods of checking and calibrat
34、ing the sieves, seeSpecification E11.5.1.2 Perforated Plate Sieves:5.1.2.1 Perforated plate sieves, made to conform to Speci-fication E 323, are available with square apertures from 125mm (5 in.) to 3.36 mm (0.132 in.) and with staggered roundapertures from 125 mm (5 in.) to 1 mm (0.038 in.). The si
35、zesof successive apertures in the series follow the same ratio as inSpecification E11for sieves.5.1.2.2 Standard frames for perforated plate sieves withapertures 4.00 mm and larger are made of hardwood or steel tohold 300-mm (12-in.), 400-mm (16-in.), or 450-mm (18-in.)square sieve plates. For apert
36、ures smaller than 4.00 mm,D 4749 87 (2007)2203-mm (8-in.) circular frames as well as the above largersquare frames may be used.5.1.2.3 In general, round hole sieves with staggered open-ings are used when sizing with sieves with opening diametersof 6.3 mm (14 in.) or larger.5.1.2.4 Where perforated s
37、ieves and wire cloth sieves areused in the same test (for example, in an analysis from 125 mm(5 in.) to 250 m (No. 60) or where results with perforatedsieves are to be compared with results with wire cloth sieves,it is better to use only square aperture sieves.NOTE 3This action should be taken prima
38、rily while performingsieving analyses on noncommercial samples, as, for instance, in prepara-tion plant component studies (see 6.5.1). In commerce, mixed series arestill customary (see 6.1.1 and 6.3.1).5.1.2.5 Results with a given square aperture and with thesame diameter round aperture are not comp
39、atible. Therefore,all reports of sieve analysis data are incomplete withoutdesignation as to the type of sieves employed (round or squareopenings).5.1.2.6 Aperture sizes of some sieves for anthracitic coal(6.3.2.1) do not conform to Specification E 323.5.2 Mechanical Sieve Shaker:5.2.1 Mechanical si
40、eve shakers are used in practically alllaboratories where frequent tests are made. They not onlyeliminate tedious hand labor, but, when properly used, willproduce more consistent results than hand sieving. They can,however, result in excessive sample degradation when properprecautions are not taken.
41、 Therefore it is important to establishand to monitor the sieving amplitude and the sieving time.5.2.2 There are several general types of mechanical sieveshakers. One type is designed to simulate hand sieving byusing a circular motion combined with a tapping action. Thistype of mechanical sieve shak
42、er is acceptable.5.2.3 A type of sieve shaker which will handle a stack ofeither round or rectangularly framed sieves and produces avigorous agitation is especially suitable for handling largesamples of coarse material. This type of mechanical sieveshaker is acceptable for handling large samples pro
43、vided it isnot overloaded and provided agitation time is limited so thatdegradation of the coal being sieved does not occur (see11.3.5).NOTE 4Some manufacturers can supply machines with reducedamplitude of vibration or variable speeds, or both, for soft materials.5.2.4 Mechanical sieve shakers can g
44、enerally be classifiedinto two types: batch (acceptable) and continuous (unaccept-able).5.2.4.1 BatchBatch mechanical sieve shakers are those inwhich a controlled quantity of coal is placed into the apparatusand mechanical action is initiated. After a controlled timeperiod, mechanical action is comp
45、leted and the size fractionsare removed from the horizontal sieves. These types ofmechanical sieve shakers are acceptable.5.2.4.2 ContinuousContinuous mechanical sieve shakersare unacceptable for the purpose of this test method. Continu-ous mechanical sieve shakers are those in which a continuousstr
46、eam of coal is fed into the apparatus and over a set ofinclined sieves. The retention time on these sieves dependsupon the degree of inclination, the throw of the sieves, and thefrequency of mechanical action. The various size fractions arecollected in individual containers in a continuous stream.6.
47、 Standard Series of Sieves6.1 Crushed Bituminous, Subbituminous, and LigniticCoals:6.1.1 For crushed bituminous, subbituminous, and ligniticcoals, the standard series of sieves shall utilize round-holeperforated plate sieves for sieves with opening diameters of 6.3mm (14 in.) or larger and wire-clot
48、h (U.S.A. Standard) sieveswith square openings for sieves with openings smaller than 6.3mm (14 in.).6.1.2 For the purpose of simplifying communication be-tween concerned parties, the following series of sieves shall beconsidered as the standard series for crushed bituminous,subbituminous and ligniti
49、c coals:Round Hole Perforated Plate Sieves200 mm (8 in.) 37.5 mm (112 in.)150 mm (6 in.) 31.5 mm (114 in.)125 mm (5 in.) 25.0 mm (1 in.)100 mm (4 in.) 19.0 mm (34 in.)75 mm (3 in.) 12.5 mm (12 in.)63 mm (212 in.) 9.5 mm (38 in.)50 mm (2 in.) 6.3 mm (14 in.)Wire Cloth (U.S.A. Standard) Sieves with Square Openings4.75 mm (No. 4) 300 m (No. 50)2.36 mm (No. 8) 150 m (No. 100)1.18 mm (No. 16) 75 m (No. 200)600 m (No. 30) 38 m (No. 400)6.1.3 For crushed bituminous, subbituminous, and ligniticcoals, an alternate standard series of sieves can utili
