Corrosion Reason Analysis of 6E-4 Tube Bundle Heat Exchanger in Hydrogen Manufacturing Plant

The reason of leakage of low-pressure-convert-gas heat exchanger 6E-4 tube bundle in a hydrogen manufacturing plant of a petrochemical company.The results indicated that the essential leakage reason of 6E-4 tube bundle was the stress-corrosion of 0Cr18Ni10Ti austenite stainless steel resulted from Cl- contained in the shell-side cooling water.In addition, the temperature of the cooling water surpassed the normal temperature, resulting in severe scalling.The crack sources were formed from the region of under-scale-corrosion, the chlorine ions were concentrated,and thus the stress-corrosion was speeded up.The means of material quality upgrading,water quality controlling and process technology improvement could ensure long-period operation for the heat exchanger.