ASTM B956-19 pdf can be downloaded on www.freestandardsdownload.com.The title is Standard Specification for Welded Copper and Copper-Alloy Condenser and Heat Exchanger Tubes with Integral Fins.
A net friend,who comes from America,shared this standard.The detail is as follows:
ASTM B956-19 establishes the requirements for heat exchanger tubes manufactured from forge-welded copper and copper alloy tubing in straight lengths on which the external or internal surface, or both, has been modified by cold forming process to produce an integral enhanced surface for improved heat transfer.
Chemical Composition
The material shall conform to the chemical compositional requirements in Table 1 for Copper UNS No. designation specified in the ordering information.
The composition limits do not preclude the presence ofother elements. By agreement between the manufacturer and purchaser, limits may be established and analysis required for unnamed elements.
