1.1 This specification establishes requirements for seamless and welded copper-nickel tubes from 0.250 to 2.125 in. (6.35 to 54.0 mm) in diameter for use in heat exchangers in water desalting plants. The following alloys are involved:This guide establishes requirements for seamless and welded copper-nickel tubes for use in heat exchangers in water desalting plants. Seamless tubes shall be manufactured by hot extrusion or piercing, and subsequent cold working and annealing as to pro