This document is the American National Standard specification for electric-fusion-welded austenitic chromium-nickel alloy steel pipe for high-temperature service. It covers 19 grades of alloy steel pipe in 5 classes, with requirements for double or single welding processes, radiography testing, and filler metals. The specification provides terminology, ordering information, material and product requirements, inspection, testing, marking and certification procedures. It references other ASTM, ASME, AWS and SAE standards for test methods, welding procedures, and numbering systems.