【国外标准】 Standard Practices for Sampling Ferroalloys and Steel Additives for Determination of Chemical Composition

4.1 These practices for the sampling of ferroalloys and steel additives are intended for use with test methods used to demonstrate compliance with composition specifications. It is assumed that all who use these methods will be trained samplers capable of performing common sampling procedures skillfully and safely.1.1 These practices include procedures for the sampling of the various ferroalloys and steel additives, either before or after shipment from the plants of the manufacturers. They are designed to give results representative of each lot that will be comparable with the manufacturer's guaranteed analysis for the same lot. For check analysis, the purchaser may use any sampling procedure desired, but the analytical results obtained on such samples shall not be a basis for compliance or rejection, unless the procedure followed is of an accuracy equivalent to that prescribed in these methods.1.2 In sampling ferroalloys and steel additives, serious errors often occur from contamination of the samples by iron from the sampling appliances. Therefore, special precautions should be observed to avoid this source of error. Metallic iron may be removed with a magnet from nonmagnetic alloys; its estimation in other alloys requires special analytical procedures (Annex A1). To avoid this error, parts of crushers and pulverizing equipment contacting the samples shall be of steel or other material showing a high resistance to abrasion of the type involved.1.3 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 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.