【国外标准】 Standard Specification for U-Bend Seamless Copper and Copper Alloy Heat Exchanger and Condenser Tubes

18.1 For 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 orCalculated Value   Chemical composition    nearest unit in the last       right-hand significant     digit used in expressing     the limiting value  Tensile strength    nearest ksi [nearest 5 MPa]  Elongation    nearest 1 %  Expansion    nearest 1 %  Grain size    nearest multiple of 0.005 mmAbstractThis specification establishes the requirements for condenser, evaporator, and heat exchanger U-bends that are manufactured from seamless copper and copper alloy tube. The material of manufacture shall be of such quality and purity that the finished product shall have the properties and characteristics specified. The material shall conform to the chemical composition requirements specified. Tensile test, expansion test, flattening test, mercurous nitrate test or ammonia vapor test, nondestructive examination, hydrostatic test, and pneumatic test shall be made to conform to the requirements specified.1.1 This specification2 establishes the requirements for condenser, evaporator, and heat exchanger U-bend tubes that are manufactured from seamless copper and copper alloy tube.1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.3 This specification is applicable to product 2 in. [50 mm] or less, inclusive, in diameter.1.4 The product shall be produced from one of the following coppers or copper alloys, as specified in the ordering information:Copper orCopper AlloyUNS No. Previously UsedDesignation Type of Metal     C10200 OFA oxygen-free without residual deoxidantsC10300 ... oxygen-free, extra low phosphorusC10800 ... oxygen-free, low phosphorusC12000 DLPA phosphorized, low residual phosphorusC12200 DHPA phosphorized, high residual phosphorusC14200 DPAA phosphorized, arsenicalC19200 ... phosphorized, 1 % ironC23000 ... red brassC44300 Type B admiralty metalC44400 Type C admiralty metalC44500 Type D admiralty metalC60800 ... aluminum bronzeC68700 Type B aluminum brassC70400 ... 95-5 copper-nickelC70600 ... 90-10 copper-nickelC70620 ... 90-10 copper-nickel-(modified for welding)C71000 ... 80-20 copper-nickelC71500 ... 70-30 copper-nickelC71520 ... 70-30 copper-nickel-(modified for welding)C72200 ... copper-nickel(A) Designations listed in Classification B224.1.5 The following safety hazard caveat pertains only to the test methods described in this specification.1.5.1 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 determine the applicability of regulatory limitations prior to use. (Warning—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for additional information. Users should be aware that selling mercury and/or mercury containing products into your state or country may be prohibited by law.)1.6 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.