scope:

This specification² covers minimum-wall thickness, seamless ferritic and austenitic steel, boiler and superheater tubes and austenitic steel heat-exchanger tubes, designate Grades T5, TP304, etc. These steels are listed in Tables 1 and 2, respectively.

Grades TP304IL TP304N, TP316H, TP316N, TP321H, TP341H, and TP348H are modifications of Grades TP304, TP316, TP321, TP347, and TP348, and are intended for high temperature service, such as for superheaters and reheaters.

The tubing sizes and thicknesses usually furnished to this specification are ¹/₈ in. (3.2 mm) in inside diameter to 5 in. (127.00 mm) in outside diameter and 0.015 to 0.500 in. (0.38 to 12.70 mm), inclusive, in minimum wall thickness, Tubing having other dimensions may be furnished, provided such tubes comply with an other requirements of this specification.

Mechanical property requirements do not apply to tubing smaller than ¹/₈ in. (3.2 mm) in inside diameter or 0.015 in. (0.38 mm) in thickness.

Optional supplementary requirements are provided and, when desired, shall be so stated in the order.

The values stated in inch-pound units are to be regarded as the standard.

² For ASME Boiler and Pressure Vessel Code applications see related Specification SA-213 in Section II of that Code.