This standard applies to new construction and covers pressure-temperature ratings, dimensions, tolerances, materials, nondestructive examination requirements, testing and marking for cast, forged and fabricated flanged, threaded, and welding end and wafer or flangeless valves of steel, nickel base alloys and other alloys as listed in table 1 of the standard. Wafer or flangeless valves, bolted or through-bolt types, that are installed between flanges or against a flange are treated as flanged-end valves. Alternative rules for NPS 2 1/2 and smaller valves are given in Annex G of the standard.