Scope 1.1 This specification covers average or minimum wall thickness electric resistance welded (ERW) tubing to be used for boilers, heat exchangers, condensers, and similar heat-transfer apparatus. 1.2 The tubing sizes and thicknesses usually furnished to the specification are 0.375 in. [9.5 mm] inside diameter (ID) to 1.5 in. [38 mm] outside diameter (OD) and 0.020 to 0.079 in. [0.5 to 2 mm], inclusive, in wall thickness. Tubing having other dimensions may be furnished provided such tubes comply with all other requirements of this specification. 1.3 The steel materials shall have the (1) external tube surface, (2) internal tube surface, or (3) both internal and external tube surfaces textured to improve heat transfer or fluid flow or both. Textured surface(s) are produced by cold forming a specified configuration on the surface(s) of base strip material before welding. 1.4 Optional supplementary requirements are provided and, when desired, shall be so stated on the purchase order. 1.5 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the 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 nonconformance with the standard. The inch-pound units shall apply unless the “M” designation (SI) of the product specification is specified in the order. 1.6 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. 1.7 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.
