1.1 This specification 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.

1.2 Units - The values stated in either inch-pounds units or SI units are to be regarded separately as the standard. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems could result in non-conformance with the specification.

1.2.1 Within the text, the SI units are shown in brackets.

1.3 The tubes are typically used in surface condensers, evaporators, and heat exchangers.