【国外标准】 Standard Specification for Welded Brass Tube

19.1 For the purpose of determining compliance with the specified limits for requirements of the properties listed in the following table, an observed value or a calculated value shall be rounded as indicated in accordance with the rounding method of Practice E29:Property Rounded Unit for Observed or Calculated Value Chemical composition Hardness nearest unit in the last right-hand place of figures of the specified limitTensile strength nearest ksiGrain size up to 0.060  mm, incl nearest multiple of 0.005 mmAbstractThis specification establishes the requirements for round, rectangular, and square copper alloy welded tube for general engineering applications. The tubes are classified into four types: Type I tubes which are finished by passing through sizing and straightening rolls at ambient temperature; Type II tubes which are finished by sizing, straightening, and annealing; Type III tubes which are finished by cold reducing or cold drawing over a plug or mandrel; and Type IV tubes which are finished by cold drawing over a plug or mandrel and annealing, and redrawing and annealing when necessary to conform to a specified size and temper. Tubes shall be welded by any process which produces forged or fusion welds. Forged-welded tube shall be scarfed to remove both internal and external flash. Forged-welded tube to be drawn over a mandrel to produce Types III and IV may have the internal flash completely removed. Fusion-welded tube shall be mechanically worked to produce a smooth external and internal surface without the application of scarfing or other removal of the weld metal bead. Grain size and mechanical properties such as tensile strength and Rockwell hardness shall be determined. The tubes shall be subjected to mercury nitrate, expansion, flattening, and reverse bend tests for performance evaluation. Non-destructive tests such as eddy-current test, hydrostatic test, and pneumatic tests shall be done as well.1.1 This specification establishes the requirements for round, rectangular, and square copper alloy welded tube for general engineering applications.1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.3 The following safety hazard caveat pertains only to the test method(s) described in this specification:1.3.1 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 to 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.