ASME B16.47, developed by the American Society of Mechanical Engineers, is a critical standard for large-diameter pipe flanges and flanged fittings. It covers two main series: Series A (based on API 605) and Series B (derived from MSS SP-44), with sizes ranging from NPS 26 to NPS 60. The standard specifies dimensions, materials, pressure-temperature ratings, tolerances, and marking requirements. It's widely used in oil, gas, petrochemical, and power industries globally, ensuring interchangeability, structural integrity, and safety of large-diameter flanged connections. By standardizing these components, it simplifies design, manufacturing, and installation processes for heavy-duty piping systems.