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Regarding the causes and mechanisms of metal stress corrosion caused by gas, this type of corrosion problem can be systematically mitigated through four approaches: material selection, surface protection, electrochemical protection, and environmental control. First, optimize material selection by giving priority to corrosion-resistant alloys that are resistant to stress corrosion, such as special alloys containing elements like Ni, Cr, and Mo, as alternatives to ordinary carbon steel； For gas conditions with high H₂S content, specialized pipes that have undergone low-hardness quenching and tempering treatment are used to reduce the stress corrosion susceptibility of the material at its source. II. Surface Coating Protection: The pipe surface is first pre-treated through shot blasting, after which special anti-corrosion coatings such as melt-bonded epoxies and self-healing metal coatings are applied to prevent corrosive agents in gas, including H₂S and moisture, from coming into contact with the metal substrate. ZnNb and ZnCr coatings prepared by cold spraying can provide long-term self-healing protection under gas conditions. III. Electrochemical protection: A cathodic protection system is implemented to maintain the metal surface in a state of cathodic polarization by precisely controlling the protection current density, thereby preventing hydrogen atoms from penetrating into the metal. The effectiveness of the cathodic protection is checked regularly each year to identify areas where the coating may be peeling off. IV. Regulation of environmental conditions: Dehydration devices are installed in gas transmission systems to reduce the moisture content in the gas, thereby eliminating the underlying conditions that lead to electrochemical corrosion ； At the same time, imidazoline-based corrosion inhibitors can be added to the system to neutralize acidic corrosive agents, thereby significantly reducing the likelihood of stress corrosion.