General This Standard Practice covers pressure-temperature ratings@ materials@ dimensions@ tolerances@ marking@ and testing for steel pipeline flanges. The welding neck type flanges shall be forged steel@ and the blind flanges may be made from either forged steel or from steel plate. Dimensional and tolerance requirements for NPS 10 and smaller are provided by reference to ASME B16.5. When such flanges are produced from materials meeting Table 2 requirements@ and meet all other stipulations of this Standard Practice@ then they shall be considered as complying therewith.