What does external pressure design use?

What does external pressure design use?

• A. UG-16 charts
• B. ASME VIII charts
• C. API charts
• D. UG-28 charts

Answer: (D)

External pressure design is all about preventing buckling when a vessel or its heads are subjected to pressure from the outside. The standard way to handle this in ASME Section VIII, Division 1 is to use the UG-28 charts. These charts provide the relationship between the shell geometry (outer diameter, wall thickness, and the relevant unsupported length or radius of curvature), material properties (through allowable stresses), and the external pressure that the shell can safely resist without collapsing. They are specifically tailored for the buckling behavior that occurs under external loading, which is different from the stresses generated by internal pressure. The other options don’t serve this exact purpose within ASME VIII. UG-28 is the designated tool for external-pressure buckling checks, whereas API charts belong to API standards rather than the ASME code, and UG-16 or generic ASME VIII charts cover other design aspects or methods not focused on external buckling.

External pressure design is all about preventing buckling when a vessel or its heads are subjected to pressure from the outside. The standard way to handle this in ASME Section VIII, Division 1 is to use the UG-28 charts. These charts provide the relationship between the shell geometry (outer diameter, wall thickness, and the relevant unsupported length or radius of curvature), material properties (through allowable stresses), and the external pressure that the shell can safely resist without collapsing. They are specifically tailored for the buckling behavior that occurs under external loading, which is different from the stresses generated by internal pressure.

The other options don’t serve this exact purpose within ASME VIII. UG-28 is the designated tool for external-pressure buckling checks, whereas API charts belong to API standards rather than the ASME code, and UG-16 or generic ASME VIII charts cover other design aspects or methods not focused on external buckling.