Api: Specification 6a 21st Edition Pdf Link

API 6A defines specific material classes (AA through HH) based on the corrosiveness of the well fluids (ranging from general service to sour service requiring NACE MR0175/ISO 15156 compliance). It mandates strict charpy impact testing, tensile testing, and hardness testing to prevent catastrophic brittle fractures. 2. Design Validation (PR1 vs. PR2)

The 21st edition represented a "total revision" and reorganization of the standard: American Petroleum Institute | API api specification 6a 21st edition pdf link