What impact does high temperature H₂ corrosion have on equipment life?
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High-temperature H₂ corrosion will significantly shorten the service life of petrochemical hydrogen equipment. The specific effects can be divided into the following aspects:: High-temperature hydrogen corrosion will directly reduce the structural life of the equipment. High-temperature hydrogen corrosion will cause decarburization of the steel, internal micro-cracks, and continuously weaken the mechanical strength of the metal. Hydrogen equipment that can originally serve for more than 10 years may directly reduce its life by 30% to 50% without targeted protection, or even crack and fail prematurely. Accelerate the aging process of equipment. Hydrogen atoms continue to invade the metal matrix at high temperatures, destroying the original stable organizational structure of the steel, causing the equipment's ability to resist erosion and medium erosion to rapidly decrease. The corrosion rate increases exponentially with the increase in temperature and hydrogen partial pressure, further compressing the normal service life of the equipment. Indirectly shortening the effective operating life, wall thickness thinning and local leakage problems caused by corrosion will force the equipment to frequently shut down for maintenance and replacement of parts, significantly increasing the length of unplanned downtime. The actual effective operating life of the equipment is far lower than the design expectation, and at the same time pushing up the operation and maintenance costs. Inducing the risk of sudden failure When corrosion accumulates to a certain extent, internal micro-cracks will rapidly expand and connect, and malignant accidents such as pipe bursts and cracks may occur at a stage far below the design life, directly leading to early scrapping of the equipment.
After reading the poster’s sharing, the analysis is very accurate! High-temperature H₂ corrosion is indeed a long-standing problem in hydrogen-facing equipment, especially the hidden dangers caused by decarburization and micro-cracks. In many cases, they cannot be discovered at the early stage, and by the time they are detected, they are often already serious. I would like to add some practical experience for reference.: In terms of material selection, for high-temperature hydrogen working conditions, it is generally recommended to use 2.25Cr-1Mo or improved Cr-Mo steel, which can significantly improve hydrogen corrosion resistance, but the specific grade must be selected based on the operating temperature and hydrogen partial pressure. During operation, try to control temperature fluctuations and avoid frequent rapid cooling and heating, otherwise hydrogen penetration and stress superposition will accelerate crack expansion. Regular ultrasonic or metallographic re-examination is necessary, paying special attention to welded joints and heat-affected zones, where many failure cases begin. Of course, this is just personal experience, and the working conditions of different devices vary greatly. For the final material selection and protection plan, it is recommended to consult a professional corrosion engineer or refer to relevant standards (such as API RP 941) based on specific design parameters. If it is convenient for the poster, you can further share the operating temperature and hydrogen partial pressure range of your equipment, and we can talk in depth~