1.1 This specification covers the requirements for welded and seamless carbon steel pipe nipples, black and zinc-coated (hot-dip galvanized), and welded and seamless austenitic stainless steel pipe nipples in standard steel pipe sizes fro This specification covers welded and seamless carbon steel and austenitic stainless steel pipe nipples. The mechanical requirements stated that, pipe nipples shall be made from new, hydrostatic tested or NDE-tested pipe, pipe and nipples shall be threa