This specification covers seamless and welded black and hot-dipped galvanized steel pipe in NPS 1/8 to NPS 26. The steel categorized in this standard must be open-hearth, basic-oxygen or electric-furnace processed and must have the following chemical requirements: carbon, manganese, phosphorus, sulfur, copper, nickel, chromium, molybdenum, and vanadium. The tubing shall undergo a seamless or welding process. Tension, bend, and flattening tests shall be performed to make sure that it must adhere to the mechanical properties of the standard. The hydrostatic test shall be applied, without leakage through the weld seam or the pipe body. Nondestructive electric test shall be made to make sure that the full volume of the pipe must be in accordance with the standard. The purchaser shall have the right to perform any of the inspections and tests set forth in this specification where deemed necessary to ensure that the pipe conforms to the specified requirements.

1.1 This specification covers seamless and welded black and hot-dipped galvanized steel pipe in NPS ¹/₈ to NPS 26 [DN 6 to DN 650] (Note 1), inclusive, with nominal wall thickness (Note 2) as given in Table X2.2 and Table X2.3. It shall be permissible to furnish pipe having other dimensions provided that such pipe complies with all other requirements of this specification. Supplementary requirements of an optional nature are provided and shall apply only when specified by the purchaser.

Note 1—The dimensionless designators NPS (nominal pipe size) [DN (diameter nominal)] have been substituted in this specification for such traditional terms as “nominal diameter,” “size,” and “nominal size.”

Note 2—The term nominal wall thickness has been assigned for the purpose of convenient designation, existing in name only, and is used to distinguish it from the actual wall thickness, which may vary over or under the nominal wall thickness.