1.1 This specification covers seamless and straight-seam welded austenitic steel pipe intended for high-temperature and general corrosive service.
1.2 Grades TP304H, TP309H, TP309HCb, TP310H, TP310HCb, TP316H, TP321H, TP347H, and TP348H are modifications of Grades TP304, TP309Cb, TP309S, TP310Cb, TP310S, TP316, TP321, TP347, and TP348, and are intended for high-temperature service.
1.3 Optional supplementary requirements are provided for pipe where a greater degree of testing is desired. These supplementary requirements call for additional tests to be made and, when desired, one or more of these may be specified in the order.
1.4 The ASTM table lists the dimensions of welded and seamless stainless steel pipe as shown in ANSI B36.19. Pipe having other dimensions may be furnished provided such pipe complies with all other requirements of this specification.
1.5 Grades TP321 and TP321H have lower strength requirements for pipe manufactured by the seamless process in nominal wall thicknesses greater than 3/8 in. [9.5 mm].
1.6 The values stated in either inch-pound units or SI units are to be regarded separately as the standard. (A combination of values from the two systems may result in nonconformance with the specification.) The inch-pound units shall apply unless the "M" designation of this specification is specified in the order.