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:
| Copper or | Type of Metal |
| C70600 | 90-10 copper-nickel |
| C70620 | 90-10 copper-nickel |
| C71500 | 70-30 copper-nickel |
| C71520 | 70-30 copper-nickel |
| C71640 | copper-nickel-iron-manganese |
| C72200 | copper-nickel |