1、Designation: E 276 03 (Reapproved 2008)1Standard Test Method forParticle Size or Screen Analysis at No. 4 (4.75-mm) Sieveand Finer for Metal-Bearing Ores and Related Materials1This standard is issued under the fixed designation E 276; the number immediately following the designation indicates the ye
2、ar oforiginal adoption or, in the case of revision, 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.1NOTEEditorial corrections were made throughout in September 2008.
3、1. Scope1.1 This test method covers the determination of the sizedistribution by screen analysis, dry or wet, of metal-bearingores and related materials at No. 4 (4.75-mm) sieve and finer.1.2 The values stated in inch-pound units are to be regardedas standard. The SI values given in parentheses are
4、providedfor information only and are not considered standard.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 and health practices and determine the applica-
5、bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E11 Specification for Wire Cloth and Sieves for TestingPurposesE 135 Terminology Relating to Analytical Chemistry forMetals, Ores, and Related MaterialsE 882 Guide for Accountability and Quality Control in theCh
6、emical Analysis Laboratory3. Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method, referto Terminology E 135.4. Summary of Test Method4.1 The sample is passed through a bank of standard sievesby agitation. The dry screening technique described in this testmethod may be
7、used on any solid particles that can be dried sothat sieve blinding does not occur. The wet screening techniqueusing liquid media may be used on any insoluble solids.5. Significance and Use5.1 This test method is intended to be used for compliancewith compositional specifications for particle size d
8、istribution.It is assumed that all who use this procedure will be trainedanalysts capable of performing common laboratory practicesskillfully and safely. It is expected that work will be performedin a properly equipped laboratory and that proper wastedisposal procedures will be followed. Follow appr
9、opriatequality control practices such as those described in GuideE 882.6. Apparatus and Materials6.1 U.S. Standard Sieves, conforming to the requirements ofSpecification E11.6.2 Mechanical Sieve Shaker.6.3 Drying Oven, of appropriate size and capable of main-taining a uniform temperature at 110 C 6
10、5 C.6.4 Sample Splitter or Riffle with 1-in. (25.4-mm) opening.6.5 Scales and Weights, of adequate accuracy.6.6 Pans, for holding samples.6.7 Brass and Fiber Bristle Brushes, for cleaning sieves andpans.6.8 Special Apparatus, for wet screening, including deep-frame sieves.6.9 Water or other liquid,
11、for wet screening.7. Sample Preparation7.1 If necessary, reduce the sample by riffling or othersuitable means to obtain a test sample that will not overload thesieves, and dry at 110 C 6 5 C to constant weight.NOTE 1The size of the sample is very important in sieve analysisbecause the number of part
12、icles on a sieve surface affects the probabilityof any one particle passing through the sieve at a given time. The moreparticles there are on a sieve, the greater probability that any one particleis hindered from getting into a position to pass through the opening.Avoidoverloading the sieves.1This t
13、est method is under the jurisdiction of ASTM Committee E01 onAnalytical Chemistry for Metals, Ores, and Related Materials and is the directresponsibility of Subcommittee E01.02 on Ores, Concentrates, and Related Metal-lurgical Materials.Current edition approved Sept. 1, 2008. Published September 200
14、8. Originallyapproved in 1965. Last previous edition approved in 2003 as E 276 03.2For 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 pag
15、e onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.2 Screen the test sample from 7.1 on a No. 4 (4.75-mm)sieve. Weigh the material retained on the No. 4 sieve.8. Preparation of Apparatus8.1 Clean coarse sieves up
16、to No. 80 (180 m) with a softbrass wire brush and clean the finer sieves with a fiber brush.Clean by brushing the under side of the sieves. Gently tap thebrass frame to aid in freeing trapped particles. At times, it maybe necessary to wash the sieves in a warm soap and watersolution. After washing,
17、dry the sieves thoroughly. If wetscreening is to be used, nest selected special deep-frame sievesafter cleaning as described.NOTE 2As an alternative, ultrasonic cleaning of sieves is recom-mended.9. Standardization of Sieves9.1 Calibrate the sieves by use of calibrated glass spheres.Standard glass s
18、pheres are available through the NationalInstitute of Standards and Technology (NIST) and otherinternational standardization organizations.9.2 Use of the microscopic method in the appendix ofSpecification E11is also permissible to assure that the sievesmeet specification.10. Procedure10.1 Dry Screen
19、ing:10.1.1 For Samples Containing Less than 10 % Passing aNo. 200 (75-m) SieveNest the selected sieves and fit a panbelow the bottom sieve. Place the material which passed theNo. 4 (4.75-mm) sieve from 7.2, in the top sieve. Cover andclamp the nested sieves in the mechanical shaker and shake forthe
20、time interval specified in 10.1.3.10.1.2 For Samples Containing More than 10 % Passing aNo. 200 (75-m) SieveWash the material which passed theNo. 4 (4.75-mm) sieve from 7.2 on a No. 200 (75-m) sieveuntil the solution passing through the sieve is clear (see 10.2).Save the material passing the sieve.
21、Dry the sieve fractions inaccordance with 10.2.4.2 and process the retained fraction inaccordance with 10.1.1.10.1.3 Length of Screening Time or End PointThe screen-ing time or end point is when additional periods of shaking failto change the results on any sieve used in the test by more than0.3 %.
22、The screening time may vary from 3 to 30 min or moredepending on the type of material. Determine the exact time foreach material experimentally.10.1.4 WeighingRemove the clamp and cover. Transferthe contents of each sieve to a tared pan, tapping and brushingthe sieves to remove any lodged particles.
23、 Record the weight ofeach sieve fraction.10.1.4.1 Weigh and record material washed on a No. 200(75-m) sieve, as described in 10.1.2 and submitted to wetscreening as described in 10.2, the same as in the other sieves.10.1.5 CalculationSum the weights of each of the sievefractions. The total shall be
24、within 1 % of the weight of theoriginal test sample or the analysis must be repeated from 7.1with another test sample. The weight of the test sample used forcalculation is the total of the sieve fractions. Calculate thepercent retained on each sieve as follows:Material retained, % 5 Wr/Wt! 3 100 (1)
25、where:Wr= mass retained on each sieve, andWt= total mass of all sieve fractions.Calculate the percent passing the finest sieve as follows:Material passing, % 5 Wp/Wt! 3 100 (2)where:Wp= mass passing the finest sieve, retained on a pan orfilter, andWt= total mass of all sieve fractions.Obtain the per
26、cent cumulative by adding each percentretained on each sieve as the series progresses.10.1.6 Report:10.1.6.1 Report the following data: sieve size, weight re-tained on or passing through sieve, percent retained on sieve,and percent cumulative.10.1.6.2 Present the data of a screen analysis graphicall
27、y asa cumulative direct plot or a cumulative logarithmic plot. Fromthe plots, the percentages remaining on any set of openingsother than those of the testing sieves used, can be found byinterpolation and in this way the redistribution of the samematerial by any assumed set of openings can be determi
28、ned.10.2 Wet Screening:10.2.1 Wet screening can be carried out on a single sieve byhand washing or through use of a mechanical shaker. Similarly,a nest of screens can be used preferably through use of aspecially adapted mechanical shaker.10.2.2 Washing of a sample on a single sieve causes thefinest
29、particles to be removed quickly from the larger or coarserparticles. It also has the advantage of breaking up aggregates offine particles and removing the slime coatings from coarseparticles, making a product more amenable to dry sieveanalysis. The liquid used for washing is generally water, but for
30、specific cases some other nonreacting liquid can be used. Drythe retained fraction and return to the sieve or nest of sieves fordry screening as described in 10.1.10.2.3 For more accuracy or reproducibility of tests, use acontrolled volume of liquid. To accomplish the results re-quired, a set volume
31、 of liquid cannot be determined to meet allconditions, but through experimentation for specific cases,such requirements can be accomplished.10.2.4 Single Screen Testing:10.2.4.1 Place the material which passed the No. 4 (4.75-mm) sieve from 7.2 in a deep-frame sieve. Wash the materialon the screen i
32、n accordance with 10.2. Continue washing untilthe liquid passing the sieve is clear.10.2.4.2 DryingWash the material on the sieve into adrying pan. Dry in an oven at 110 C 6 5 C. Recover thematerial from the retained washings by using a filter press or byevaporation, then dry in an oven at 110 C 6 5
33、 C.10.2.4.3 Weighing, Calculation, and ReportTransfer thecontents of the sieve to a tared pan as described in 10.1.4 andweigh. Calculate and report the data as described in 10.1.5 and10.1.6.10.2.5 Multiple Screen Testing:10.2.5.1 Nest the selected deep-frame sieves and fit a pancontaining a drain pi
34、pe to the bottom sieve. Place the materialE 276 03 (2008)12passing the No. 4 (4.75-mm) sieve from 7.2 into the top sieve.Place a sieve cover equipped with two inlet pipes on the topsieve and clamp the nested sieves in the mechanical shaker.Connect the inlet pipe to the liquid supply and the drain pi
35、pe toa collection container. Start the mechanical shaker and turn onthe liquid supply. Continue the washing until the dischargeliquid is clear. Turn off the liquid supply and allow the shakerto continue operation for a few minutes.10.2.5.2 Remove the sieves from the shaker, and dry thesieve fraction
36、s in accordance with 10.2.4.2.10.2.5.3 Weighing, Calculation, and ReportTransfer thecontents of the sieves to tared pans as described in 10.1.4 andweigh. Calculate and report the data as described in 10.1.5 and10.1.6.11. Precision and Bias11.1 PrecisionIt is generally agreed that errors in screen-in
37、g arise from the way in which screening is done. Selection ofthe sample loading of the sieves, sieves themselves, and thefinal weighing, all influence the reproducibility or accuracy ofscreening. Some particle wear occurs, but for the No. 4 andfiner sieves, this wear is usually insignificant. Brittl
38、eness,hardness, weight of charge, and the mode of operation of themechanical shaker influence slightly the results of the test. It isagreed, however, that normally any variations due to thesefactors would not effectively alter the results of the test. Thesize and shape of the particles significantly
39、 influence theprobability of passing when sizes of aperture and particle areclose. Screening time is important, but it cannot be said that aspecific time of screening should be used for all types ofmaterials. End point of time of screening for different materialsis to be established by experimentati
40、on.11.2 If the sample is known to contain naturally occurringferromagnetic material, it shall be demagnetized in a 60-Hzfield of not less than 300 Oe.11.3 It is not practicable to specify the precision of theprocedure in this test method because the precision is related tothe quantity of sample test
41、ed, the distribution of particles andthe shape of the particles, which vary for each type of materialtested.11.4 BiasNo information on the accuracy of this testmethod is known. The accuracy of this test method asmeasured by calibration of sieves using standard referencematerials, is not directly tra
42、nsferable to metal-bearing ores andrelated materials.12. Keywords12.1 analyzing; ores; particle size; related materials; screenanalysisAPPENDIX(Nonmandatory Information)X1. SUMMARY OF U.S. SIEVE, TYLER SCREEN, AND ISO EQUIVALENTSU.S. Standard Sieve No. Tyler Screen Number,meshISO Designation4 4 4.75
43、 mm5 5 4.00 mm6 6 3.35 mm7 7 2.80 mm8 8 2.36 mm10 9 2.00 mm12 10 1.70 mm14 12 1.40 mm16 14 1.18 mm18 16 1.00 mm20 20 850 m25 24 710 m30 28 600 m35 32 500 m40 35 425 m45 42 355 m50 48 300 m60 60 250 m70 65 212 m80 80 180 m100 100 150 m120 115 125 m140 150 106 m170 170 90 m200 200 75 m230 250 63 m270
44、270 53 mE 276 03 (2008)13U.S. Standard Sieve No. Tyler Screen Number,meshISO Designation325 325 45 m400 400 38 mASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advis
45、ed that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either r
46、eapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If
47、you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).E 276 03 (2008)14
