This specification covers spray-formed seamless austenitic stainless steel pipe intended for high-temperature and general corrosive service. The steel shall conform to the specified chemical composition and tensile requirements. The mechanical test requirement includes, transverse or longitudinal tension test, flattening test, hydrostatic test and grain size determination are presented. One tension tests shall be made on a specimen for lots of more than 100 pipes. For material heat treated in a batch-typed furnace, flattening tests shall be made on 5% of the pipe from each heat treated lot. Each length of finished pipe shall be subjected to hydrostatic tests.

1.1 This specification covers spray-formed seamless austenitic stainless 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 Appendix X1 lists the dimensions of 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 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

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

1.5.2 The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.

Note 1—The dimensionless designator NPS (nominal pipe size) has been substituted in this standard for such traditional terms as “nominal diameter,” “size,” and “nominal size.”