This standard describes a design analysis methodology and requirements that apply to design verification of certain pressure-containing products and equipment in the oil and natural gas industry. The methods included in this document apply to designs where normative reference to this standard is made in an API product specification and to those components for which the methods of this standard are required or permitted.

Methods are in accordance with the rules of Appendix 4 of the ASME Boiler and Pressure Vessel Code, 2004, Section VIII, Division 2.

API has adopted slightly different stress limits from the ASME Boiler and Pressure Vessel Code, 2004. The criteria used assume defect-free, tough, and ductile material behavior.

Fatigue analysis is outside the scope of this document. Bolting allowable stresses are given in API product specifications and are outside the scope of this document.