22 Section VIII: Division 2–Alternative Rules

This chapter covers alternative rules to the construction of pressure vessels under Section VIII, Division 2. The Section is made up of nine parts and the organization within each part is as follows: rules and requirements, nomenclature, tables, figures, normative annexes, and informative annexes. Part 1 contains general requirements addressing the following subjects: reference standards, units of measurement, tolerances, and technical inquiries. Part 2 consolidates the responsibilities and duties of the User, Manufacturer, and Authorized Inspector. It also contains general requirements for report forms and maintenance of records. Part 3 contains all requirements related to materials of construction and is organized in a similar fashion to Part AM of VIII-2. The coverage includes materials permitted for construction of vessel parts, and supplemental requirements for ferrous materials, Cr–Mo steels, Q and T steels with enhanced tensile properties, nonferrous metals, and boltings and castings. The requirements of Part 4 provide design rules for commonly used pressure vessel shapes under pressure loading and, within specified limits, rules or guidance for treatment of other loadings. Design requirements for the application of the design-by-analysis methodology in VIII-2 are described in Part 5. Detailed design procedures utilizing the results from a stress analysis are provided to evaluate components for plastic collapse, local failure, buckling, and cyclic loading. Part 6 consolidates the various fabrication requirements from old VIII-2 and VIII-1. Part 7 contains the requirements for examination during construction of pressure vessels. Part 7A covers the responsibilities and duties for inspection and examination during construction of pressure vessels. Part 8, which contains the rules pertaining to the pressure testing of the vessel following completion of fabrication, describes requirements for hydrostatic testing and pneumatic testing. The requirements for overpressure protection of vessels built in accordance with this VIII-2 are provided in Part 9.