ISO International General Pipeline Basic Standard
The ISO international piping standards are a common foundational specification system for global EPC engineering and cross-border pipeline projects. They are formulated by the International Organization for Standardization and are based on DN nominal diameter and PN nominal pressure. They include basic general guidelines such as dimensional definitions, threads, materials, and inspection, and are often used in conjunction with regional standards such as EN, ASME, GOST, and JIS. This article reviews the ISO piping foundational standards framework and core foundational specifications, explains nominal size, pressure definitions, fitting threads, and general rules for inspection and testing, compares the similarities and differences between ISO and various regional standards, and analyzes key application points and selection misconceptions in foreign trade procurement, so as to provide technical support for standardized alignment in piping and fittings foreign trade projects and reduce the risk of parameter mismatches in multinational engineering.