API 579-1 (2021) Annex 9B — Mode I stress intensity factor K_I compendium (plate & cylinder, 12 solutions)
Selects an API 579-1/ASME FFS-1 (2021) Annex 9B compendium solution by crack geometry and assembles the Mode I stress intensity factor K_I. Plate solutions cover through-wall, surface semi-elliptical, surface infinite-length and embedded flaws; cylinder solutions cover longitudinal/circumferential through-wall (with optional net-section bending) and longitudinal/360° surface flaws. Stress is entered as membrane+bending \sigma_m/\sigma_b or as a fourth-order through-wall polynomial \sigma_0..\sigma_4 (Eq 9B.3). K_I is reported in MPa·√mm (= N/mm^{1.5}; divide by 31.6228 for MPa·√m). Sibling to the BS 7910 Annex M K_I calculator — same Newman-Raju/Anderson lineage, independent API 579 coefficients. Simplified-assessment estimate; deep flaws (a/t \to 1) lose accuracy and may require re-characterization per Part 9.
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