1、Designation: D4749 87 (Reapproved 2012)Standard Test Method forPerforming the Sieve Analysis of Coal and Designating CoalSize1This standard is issued under the fixed designation D4749; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 covers
3、 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 da
4、ta 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 analys
5、is 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 1For
6、powdered or pulverized coal as is fired into steam boilers,refer to Test Method D197.1.4 The values stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly. The values stated in each system may not be exactequivalents; therefore, each system must be
7、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 determine the
8、 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D197 Test Method for Sampling and Fineness Test ofPulverized CoalD346 Practice for Collection and Preparation of CokeSamples for Laboratory AnalysisD388 Classification of Coals by RankD2013 Practice for
9、 Preparing Coal Samples for AnalysisD2234/D2234M Practice for Collection of a Gross Sampleof CoalD3302 Test Method for Total Moisture in CoalD4371 Test Method for Determining the Washability Char-acteristics of CoalE11 Specification for Woven Wire Test Sieve Cloth and TestSievesE323 Specification fo
10、r Perforated-Plate Sieves for TestingPurposes2.2 Other Document:Specification C-80 Commonwealth of Pennsylvania, Depart-ment of General Services, Bureau of Purchases, Specifi-cation for Coal:Anthracite33. Descriptions of Terms Specific to this Standard3.1 as-mined coalsame as ROM coal (3.8).3.2 as-s
11、hipped 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 which passes at
12、otal 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 of ASTM Committee
13、 D05 on Coaland Coke and is the direct responsibility of Subcommittee D05.07 on PhysicalCharacteristics of Coal.Current edition approved Sept. 1, 2012. Published November 2012. Originallyapproved in 1987. Last previous edition approved in 2007 as D474987 (2007).DOI: 10.1520/D4749-87R12.2For referenc
14、ed 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 website.3Available from Commonwealth of Pennsylvania, Dept. of General Services,Bu
15、reau of Purchases, 414 N. Office Building, Harrisburg, PA 17125.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1this designation may not be valid. In such commercial orcontractual situations, the amount of allowable materialsmaller th
16、an the 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, the testmethod for the sieving of coal after the sample has beenair-dried under prescribed conditions; this is generally usedwhen test
17、ing with 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 refe
18、r to the 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
19、, jig, 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 norma
20、lly rejects 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
21、are provided 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 transportati
22、on whether 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 us
23、ed to extract 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 t
24、he sample. 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 gen
25、erally 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 f
26、or commercial 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 D197) such as fed intosteam boilers. L
27、ow rank coals, that is, lignites, subbituminous,and high volatile bituminous C, must be dried with caution andhandled with care to minimize deterioration or size degradationduring 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. 4
28、00 U.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 s
29、uchmethods. 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.
30、This 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 D4371).PART A. SIEVE ANALYSIS OF COA
31、L5. Apparatus5.1 Sieves:5.1.1 Wire Cloth Sieves:5.1.1.1 Standard test sieves that conform to SpecificationE11 shall 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
32、 withlarger 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, phosph
33、or bronze, 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 cali
34、brating the sieves, seeSpecification E11.5.1.2 Perforated Plate Sieves:5.1.2.1 Perforated plate sieves, made to conform to Speci-fication E323, 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
35、 sizesof successive apertures in the series follow the same ratio as inSpecification E11 for sieves.D4749 87 (2012)25.1.2.2 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 sie
36、ve plates. For apertures smaller than 4.00 mm,203-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 perforate
37、d sieves 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 pr
38、imarily 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 c
39、ompatible. 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 E323.5.2 Mechanical Sieve Shaker:5.2.1 Mechanical
40、sieve 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 take
41、n. 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 sh
42、aker 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 p
43、rovided 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
44、 generally 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 co
45、mpleted 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 continuouss
46、tream 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.
47、6. 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-cl
48、oth (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 ligni
49、tic 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 ut
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