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ASTM C285-10(R2020) pdf free download

ASTM C285-10(R2020) pdf free download.Standard Test Methods for Sieve Analysis of Wet-Milled and Dry-Milled Porcelain Enamel
1. Scope
1.1 These test methods cover the determination of the fineness of frit in wet- or dry-milled porcelain enamels and other ceramic coatings for metals by means of the No. 200 (75-µm) or No. 325 (45-µm) sieve.1.3 Method A is intended for use where a referee method of higher accuracy is required, while Method B is intended to meet the needs of normal enamel plant production control operations where a rapid, simplified method of sieve testing is required. The accuracy of the simplified method has proved to be entirely adequate for this use. The simplified test, however, is not recommended where high accuracy is required. 1.4 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.5 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
4. Apparatus
4.1 Balance—The balance or scale shall be of at least 500-g capacity, and accurate to 0.1 g. 4.2 Sieves—The sieves shall conform to Specification E11. They shall include the No. 40 (425-µm) sieve and also the No. 200 (75-µm) or the No. 325 (45-µm) sieve, or both. A No. 325 sieve shall be used when the fineness is such that, from a sample containing 100 g of dry solids, less than 2 g is retained on a No. 200 sieve. An 8-in. (203-mm) full-height sieve is recommended. This height is preferred because there is less tendency to flood or splash, and also because it fits commercial automatic tapping and shaking machines. All sieves used for testing shall be standardized initially and after every 50 tests against a reference sieve tested by the National Bureau of Standards and bearing its precision seal. The correction for the sieve used in this test shall be determined by sieving tests made in conformity with the procedure of this test method. Identical samples shall be sieved through the reference sieve and the test sieve. Test materials shall be chosen so that 5 to 10 % of the material will be retained on the reference sieve. The difference between the percentage residue on the reference sieve and that on the test sieve is the amount of correction which shall be algebraically added to, or subtracted from, the correction for the reference sieve to obtain the final correction (Note 1). The No. 40 sieve need not be calibrated. N OTE 1—For example, when comparing the reference sieve with a test sieve, should 8.5 g be retained on the reference sieve and 7.5 g on the test sieve, the total correction for the test sieve would then be 8.5 − 7.5, or + 1.0. 4.3 Dryer—A suitable means for drying the sieves and slip sample, without exceeding a temperature of 250 °F (122 °C), shall be provided. No dryer is needed for sieve tests of dry-milled enamel. 4.4 Mechanically Operated Sieve Shaker—The mechanical shaking device shall be such as to produce a lateral and vertical motion of the sieve, accompanied by a jarring action so as to keep the sample moving continuously over the surface of the sieve. If a machine shaker is to be used, the thoroughness of sieving shall be tested by comparing and calibrating with the hand method of sieving, as described in Section 6.

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