ASTM A943/A943M-01(2005) - 1.9.2005
 
1. Scope

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 inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining 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.

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."

 
2. Referenced Documents

B1.20.1

Pipe Threads, General Purpose

B36.10

Welded and Seamless Wrought Steel Pipe

B36.19

Stainless Steel Pipe

SAE??J1086

Practice for Numbering Metals and Alloys (UNS)

E527-23

Standard Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS)

E381-22

Standard Method of Macroetch Testing Steel Bars, Billets, Blooms, and Forgings

E112-25

Standard Test Methods for Determining Average Grain Size

A999/A999M-23

Standard Specification for General Requirements for Alloy and Stainless Steel Pipe

A941-26a

Standard Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys (Includes all amendments and changes 4/15/2026).

A450/A450M-25a

Standard Specification for General Requirements for Carbon and Low Alloy Steel Tubes (Includes all amendments and changes 5/16/2025).

A262-15(2021)

Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels