ASTM A498/A498M-17 + Redline

1.1 This specification describes seamless or welded low-carbon steel tubes on which the external or internal surface, or both, have been modified by a cold forming process to produce an integral increased surface area for improved heat transfer. The tubes are used in tubular heat exchangers, surface condensers, evaporators, superheaters, and similar heat-transfer apparatus in outside diameters up to 2 in. [50 mm], inclusive.