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Through years of practice and by referring to the technical specifications of similar international standards, the GB/T 150 standard takes into account the following failure modes, both directly and indirectly, in its technical requirements; corresponding design criteria and strength theories are established for these failure modes: a) Brittle fracture: Brittle fracture is prevented through requirements regarding material selection, material toughness, manufacturing and inspection procedures, as well as structural design aspects. b) Ductile rupture: Ductile rupture is avoided through requirements for material selection, methods for designing structural strength, and specified allowable stresses. c) Leakage at joints: Leakage at joints is prevented through methods for designing flanges and special sealing structures, along with structural requirements and specifications for gaskets, studs, and nuts； d) Elastic or plastic instability: Preventing overall instability through external pressure structural design methods ； Local plastic instability is controlled through local stress analysis and evaluation ； e) Creep rupture: The occurrence of creep rupture is controlled by limiting the temperature range at which the material is used. Corrosion is the most common failure mode of pressure vessels. Corrosion and its prevention constitute a specialized field within the study and application of materials. Based on the process and mechanisms of corrosion, it can be classified as follows: a) Physical corrosion: Damage to metals caused by simple physical dissolution; b) Chemical corrosion: Damage to materials resulting from direct chemical reactions between the metal surface and non-electrolytic media ； c) Electrochemical corrosion: The degradation of a material resulting from an electrochemical reaction between the metal surface and an electrolyte solution, with electricity being generated during this reaction. This is also the most common failure mode of pressure vessels.