ASTM C429-21

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Designation: C429 − 16 C429 − 21
Standard Test Method for
Sieve Analysis of Raw Materials for Glass Manufacture
This standard is issued under the fixed designation C429; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the sieve analysis of common raw materials for glass manufacture, such as sand, soda-ash, limestone,
alkali-alumina silicates, and other granular materials used in glass batch.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.after
SI units are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C92 Test Methods for Sieve Analysis and Water Content of Refractory Materials
C325 Guide for Wet Sieve Analysis of Ceramic Whiteware Clays
C371 Test Method for Wire-Cloth Sieve Analysis of Nonplastic Ceramic Powders
D346D346/D346M Practice for Collection and Preparation of Coke Samples for Laboratory Analysis
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
E105 Guide for Probability Sampling of Materials
E122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or
Process
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 unit for sampling, n—a carload lot or truckload lot of bulk material, or the entire shipment of bagged material.
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3.1.2 sub lot, n—a fraction of a shipment of bagged material, such as ⁄10 or ⁄20 of the lot.
This test method is under the jurisdiction of ASTM Committee C14 on Glass and Glass Products and is the direct responsibility of Subcommittee C14.02 on Chemical
Properties and Analysis.
Current edition approved Oct. 1, 2016June 1, 2021. Published November 2016July 2021. Originally approved in 1959. Last previous edition approved in 20112016 as
C429 – 01 (2011).C429 – 16. DOI: 10.1520/C0429-16.10.1520/C0429-21.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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3.1.1 gross sample, n—the total number of sample increments taken from the lot.
3.1.2 laboratory sample, n—a 0.9 to 1.8 kg (2 to 4 lb) representative fraction of the gross sample.
3.1.3 sample increment, n—an individual portion of the gross sample taken from the lot at a definite time or location, or both;
increments shall be of nearly equal weight or volume, or both.
3.1.3.1 Discussion—
A 2.2 to 4.5-kg4.5 kg (5 to 10-lb) 10 lb) increment generally is satisfactory in sampling raw materials for glass manufacture, for
determining particle size distribution.
3.1.4 laboratory sample,sub lot, n—a 0.9 to 1.8-kg (2 to 4-lb) representative fraction offraction of a shipment of bagged material,
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such as ⁄10 or ⁄20 of the gross sample.lot.
3.1.5 test specimen, n—a 100 to 150-g 150 g representative fraction of the laboratory sample.
3.1.6 unit for sampling, n—a carload lot or truckload lot of bulk material, or the entire shipment of bagged material.
4. Significance and Use
4.1 The purpose of this test method is to determine the particle size distribution of the glass raw materials.
5. Apparatus
5.1 Testing Sieves:
5.1.1 Sieves shall conform to Specification E11 with particular reference to Table 1 and Section 4 on Frames. Sieves shall be
designated by the U. S. Standard Series of sieve numbers and shall vary in opening size by the ratio of the =2:1 in accordance
with frames 1 in. (25 mm) deep (half height) are recommended for mechanical shaking. The following sieves shall be provided:
Sieve Designation Opening Size
No. 8 2.36-mm
No. 8 2.36 mm
No. 12 1.70-mm
No. 12 1.70 mm
No. 16 1.18-mm
No. 16 1.18 mm
No. 20 850-μm
No. 20 850 μm
No. 30 600-μm
No. 30 600 μm
No. 40 425-μm
No. 40 425 μm
No. 50 300-μm
No. 50 300 μm
Sieve Designation Opening Size
No. 70 212-μm
No. 70 212 μm
No. 100 150-μm
No. 100 150 μm
No. 140 106-μm
No. 140 106 μm
No. 200 75-μm
No. 200 75 μm
5.1.2 Standard Matched Sieves—A reference set of standard matched sieves shall be provided for use in checking the set of sieves
used in the actual sieve analysis of samples. The sieves for use in sieve analysis of samples may also be standard matched sieves
or may be unmatched sieves conforming to 5.1.1, provided that such sieves will give results that differ by not more than 5 % from
those obtained with the reference set when the two sets are compared in accordance with Section 66.
5.2 Sieve Shaker—A mechanically operated sieve shaker that imparts to the set of sieves a rotary motion and tapping action of
uniform speed shall be provided. The number of taps per minute shall be between 140 and 150. The sieve shaker shall be fitted
with a wooden plug or rubber stopper to receive the impact of the tapper. Other types of mechanical shakers may be used, provided
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they can be adjusted to duplicate within 5 % results obtained by the type specified above, when tested with the same sample and
standard matched sieves. The shaker shall be equipped with an automatic timer accurate to 6 ⁄2 minutes. min.
5.3 Sample Splitters:
5.3.1 For the reduction of the gross sample to laboratory size, either a large riffle with 25-mm (1-in.) 25 mm (1 in.) openings or
a sample splitter of the type that cuts out a fractional part (for example, a twelfth or a sixteenth) of the gross sample may be used.
Sample splitters are available commercially or may be constructed by the user. The criterion for their use is that they shall produce
a representative sample.
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5.3.2 Riffles with openings of 6.4 to 13 mm ( ⁄4 to ⁄2 in.) are required for reducing the laboratory sample to test size. The riffle
opening must be at least three times the width of the largest particle diameter. This restricts use of a riffle with 6.4-mm6.4 mm
openings to materials passing a No. 8 sieve.
5.4 Balance—A suitable balance or scale capable of weighing accurately to 60.1 g shall be used. A more sensitive balance may
be used for weighing small fractions when they are considered critical.
6. Testing of Sieves and Sample Splitters
6.1 Since standard matched sieves are specified for the purpose of this test method, calibration as such by the tester is obviated.
However, the tester must have a method to check the precision of the sieves. This shall be accomplished by having available at
least two sets of sieves: a reference set and a working set. The reference set shall consist of standard matched sieves and shall be
reserved for testing the working set. The working set also may consist of standard matched sieves or of sieves the tester has proven
to be satisfactory (see 6.2). The testing of the working sieves is necessary because sieves will gradually change their characteristics
after long usage from clogging and wear. The working set should be tested after every 100 to 150 sieve analyses. The test shall
be made by sieving a suitable test sample through the working set as directed in Section 10, and then sieving the same test sample
through the reference set. The results shall be calculated and compared. All testing sieves of the working test set that give results
within 610 % of the reference set shall be considered satisfactory for use. (See Appendix X1 for an example of this test.)
6.2 A new unmatched sieve can be used if it is proven by testing that it will produce results within 65 % of a standard matched
sieve. To test an unmatched sieve, it should be substituted for the equivalent sieve in a standard matched set and a sieve analysis
made with a sample previously sieved with the complete matched set. If agreement is satisfactory, the new unmatched sieve can
be used as a working sieve.
6.3 A sample splitter for reducing a gross sample should be tested for reproducibility before it can be considered reliable. A
minimum test shall be to take three gross samples of materials, weighing 45 kg (100 lb) or more, with different particle size
distribution, and obtain four laboratory-size samples of each by repeated splitting. The laboratory samples shall be riffled to test
size and sieved. The same set of sieves shall be used for all tests. Duplication of results within each group should be within 65 %
or better.
7. Care and Cleaning of Testing Sieves
7.1 Testing sieves must be properly cared for if reproducible and reliable results are to be obtained from them. The life of a sieve
is materially lengthened by proper care and careful handling. It is inevitable that some particles will become fastened in the sieve
cloth, but excessive clogging can be controlled by brushing the underside of the wire cloth with a stiff bristle or bronze wire brush
every time the sieve is used in testing. A nylon bristle paint brush 51 mm (2 in.) in width, with the bristles cut back to about 25
mm (1 in.) long, is recommended for brushing, although any short-bristle brush that will not stick in the wire cloth is satisfactory.
A bronze wire brush should be used only for sieves No. 60 and coarser. Brushing shall be firm enough to remove the majority of
clogging particles but not so vigorous as to distort the sieve cloth. Sieves shall be washed periodically with a mild detergent or
soap, brushing on the underside of the cloth. They should be washed immediately after sieving hygroscopic materials, such as
alkali carbonates, and dried before storing. They may be dried in a drying oven at 105 to 110°C. 110 °C. A properly cared for sieve
will be clean and free of patina. It will have a minimum of clogged openings. The wire cloth will be taut in the frame and free
of distortion. The solder joint will be firm. A loosened joint on an otherwise satisfactory sieve may be repaired by carefully
soldering it with resin-core solder. Additional cleaning methods are contained in ASTM STP 447B.
ASTM STP 447B, Manual on Test Sieving Methods, ASTM STP 447B,, ASTM, ASTM International, 1985.
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8. Sampling
8.1 General Considerations—Follow the principles of probability sampling as given in Practice E105. To estimate the size (mass
and number of increments) of the gross sample, follow Practice E122. The methods used for other necessary statistical calculations
are given in ASTM STP 15D.
8.2 Sampling Plan—The sampling plan shall be such that the sample obtained will represent as nearly as practicable the average
particle size distribution of the lot. Sampling bulk material and bagged material will each present a different problem.
8.2.1 Some segregation or non-uniformity will always exist in a bulk lot of material. At rest, this non-uniformity can and probably
will be multidirectional, with some layers of segregation in the lot that are nearly perpendicular to each other. The exact degree
is never completely known. To obtain a representative cross section of the lot is difficult, if not impossible. In motion, however,
some mixing occurs, and segregation will tend to become unidirectional with layers of segregation generally parallel to the
direction of flow. Therefore, a sample increment taken by uniformly cutting across the flowing stream is generally much more
nearly representative than an increment taken with the material at rest. An entire lot should be sampled by taking a number of
increments spaced at nearly equal intervals during the whole time of loading or unloading of the car or truck. To take frequent cuts
(sample increments) of all of the stream part of the time reduces the danger of a biased sample. Furthermore, when sampling a
moving stream, the requirement for randomness is more nearly met at the time and place of sampling since the chance of taking
one grain instead of another is about equal. The total number of increments required for a desired precision can be estimated
statistically as in Practice E122. Some simple device is required to sample the stream. This may consist of a box-type cutter for
sampling the stream discharging from the end of a belt or spout, or a scoop for sampling the stream being transported on the belt.
(See Appendix X2 for illustrations of simple stream samplers.) For the purpose of this test method, a sampling plan that provides
for sampling the moving stream is recommended. The sampling of a car or truckload lot of material at rest, by shovel, scoop and
cylinder, or thief is not recommended.
8.2.2 In sampling bagged material, an added problem is presented—that of choosing which bags of the lot will be taken for
sampling and how the bags taken are to be sampled. A suitable plan for taking bags for sampling would be to divide the lot into
sub lots and then to take at random one bag from each sub lot. This would afford a simple cross section of the lot and a random
selection in each sub lot. The number of sub lots in which to divide the lot should be calculated using the same considerations as
for estimating the number of increments to be taken when sampling bulk material. The consideration of segregation within bags
must not be overlooked. If a suitable sample splitter is available, the entire contents of the bag can be taken and segregation
ignored. However, if the bag is sampled with a thief, or by some other method, it must be made certain that any segregation is
taken into account. A bag of granular material, particularly after shipping, can show visible evidence of segregation. If stratification
or segregation has occurred, care must be taken to sample so as not to obtain a biased or “weighted” sample. The samples obtained
from the bags are mixed to constitute the gross sample.
8.3 Gross Sample Requirement—Because of the many ways of handling materials and, in many cases, the limitations so imposed
on sampling, and because of the several kinds of materials used for glass making, a single sampling plan is not prescribed. Only
certain minimum considerations are presented and recommendations made. However, for the purpose of this test method, any plan
devised or used shall produce—or as near thereto as it is practicable to obtain—a gross sample that has a 99.7 % probability that
the minimum precision of the estimate will be 10 % relative for the critical particle size fraction (Note 1). (See Appendix X3 for
calculation and discussion of this requirement.)
NOTE 1—A critical particle size fraction is considered to be one upon which a specification for purchase or use is based.
9. Reduction of the Sample for Analysis
9.1 The gross sample obtained by combining all of the increments shall be reduced to laboratory sample size of 0.9 to 1.8 kg (2
to 4 lb) by use of a large riffle with 25-mm (1-in.) 25 mm (1 in.) openings or by a sample splitter. If the material is too moist to
flow freely in a small riffle, it shall be dried before further handling (9.1.2). The laboratory sample shall be reduced to test specimen
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size, using a riffle with 6.4 to 13-mm 13 mm ( ⁄4 to ⁄2-in.) in.) openings. It shall be divided until the fractional portion weighs
approximately 100 to 150 g. This whole fraction constitutes the test specimen. An exception to the above weight for the test
specimen is burned dolomite. Because of its light density, the dolomite shall be riffled to a test size weighing 50 to 75 g. The test
specimen shall be weighed to the nearest 0.1 g before sieving.
ASTM STP 15D, Manual on Presentation of Data and Control Chart Analysis, ASTM STP 15D, ASTM, ASTM International, 1986.
Taggart, A. F., Handbook of Mineral Dressing, Ores & Industrial Minerals, John Wilcox & Sons, New York, NY, 1945.
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9.1.1 When reduction of the gross sample or laboratory sample to test size by the means described in Section 8 is not feasible,
hand reduction by the cone and quarter method may be used. The applicable portions of this method as described in Test Method
D346D346/D346M shall be followed.
9.1.2 Most materials can be dried at 105 to 120°C. 120 °C. However, naturally hydrated materials such as gypsum, if dried, must
not be heated above the critical temperature of the hydrate. Gypsum would best be dried in a stream of dry air or a desiccator.
10. Procedure for Mechanical Sieving
10.1 Assemble in order the selected sieves, which shall vary in opening size by the ratio of =2:1, with the coarsest on top and
a pan on the bottom. Place the test specimen on the top sieve, close the nest of sieves with a cover, and place the entire assembly
on the shaker. Shake the sieves for the time specified in 10.2. After shaking for the specified time, stop the shaker, remove the
sieves, and weigh each separated fraction to the nearest 60.1 g.
10.2 Shaking Time—The shaking time for this test method is as follows:
Time, min
Sodium carbonate (soda ash) 10
A
Potassium carbonate (potash) 5
All other materials 10
—————
A
The finest sieve used shall be the No. 50.
11. Procedure for Burned Dolomite (Note 2)
11.1 Before shaking, mix 1 g of tri-calcium phosphate into the test specimen of burned dolomite by rolling back and forth on a
sheet of glazed paper. Sieve the specimen in the regular manner. Subtract the added gram from the pan for calculation. The addition
of tri-calcium phosphate imparts a free-flowing character to the burned dolomite, preventing balling and blinding of the sieve. This
additive will permit sieving through a No. 140 sieve. If sieving through a No. 200 sieve is desired, an additional 10 min of shaking
may be necessary. However it may be found that sieving through a No. 200 will not be successful. In any case, remove all fractions
except that remaining on the No. 200 sieve and weigh before continuing.
NOTE 2—Within the lime industry burned dolomite is classified also as ground, screened, or pulverized quicklime.
12. Procedure for Hand Sieving
12.1 Hand sieving is not a standard procedure for the purpose of this test method. However, if necessity requires hand sieving a
material, follow the procedure described in Section 8 on Hand Sieving in Test Methods C92.
13. Procedure for Wet Sieving
13.1 When the sizing of finely ground materials on sieves finer than No. 200 is required, they shall be wet sieved. For the purpose
of this test method the foll
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