Реферат

This specification covers the requirements for design and construction of testing sieves using a medium of woven wire cloth mounted in a frame for use in testing for the classification of materials according to designated particle size and wire cloth meeting the specifications specified, to be designated test grade wire cloth. Frames for wire cloth sieves shall be constructed in such a manner as to be rigid. The wire cloth shall be mounted on the frame without distortion, looseness or waviness. To prevent the material being sieved from catching in the joint between the wire cloth and the frame, the joint shall be filled smoothly or constructed so that the material will not be trapped. Standard frames for the sieve frames shall be circular with specific nominal diameters. The dimensions shall conform to the specified requirements. These frames shall be made from non corrosive material such as brass or stainless steel and be of seamless construction. The nonstandard frames for sieve frames may be either square, rectangular, or circular. The frame may have the sieve cloth permanently installed, or may be designed to permit replacement. Pans and covers for use with sieves shall be made so as to nest with the sieves. Pans with extended rims (“stacking skirts”) shall be furnished when specified. The pans and covers shall conform to the specified dimensions.

Область применения

1.1 This specification covers the requirements for design and construction of testing sieves using a medium of woven wire cloth mounted in a frame for use in testing for the classification of materials according to designated particle size (See Note 1 and Note 2), and wire cloth, meeting the specifications of , to be designated test grade wire cloth. All subsequent references to wire cloth shall mean test grade wire cloth. Methods for checking testing sieves and wire cloth for conformance to this specification are included in the annex.

Note 1--Complete instructions and procedures on the use and calibration of testing sieves are contained in ASTM STP447B. Note that sieve analysis results from two testing sieves of the same sieve designation may not be the same because of the variances in sieve opening permitted by this specification. To minimize the differences in sieve analysis results, the use of testing sieves matched on a performance basis is suggested. ASTM STP447B also contains a list of all published ASTM standards on sieve analysis procedures for specific materials or industries. This list may be referenced to obtain statements of precision and bias for sieve analysis of specific materials.

Note 2--For other types of sieves, see Specification E323 and Specification E161.

1.2 The values stated in SI units shall be considered standard for the dimensions of the wire cloth openings and the diameter of the wires used in the wire cloth. The values stated in inch-pound units shall be considered standard with regard to the sieve frames.

1.3 The following precautionary statement refers only to the test method portion, Annex A1, of this specification: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 and health practices and determine the applicability of regulatory limitations prior to use.