Abstract: Aiming at the frequent occurrence of local material fracture, perforation and thinning in the inlet and outlet pipes of convertor and process syngas waste heat boilers at home and abroad in recent 15 years, this paper analyzes the stress release cracks in the collecting main, high-temperature hydrogen corrosion in the outlet cold-wall collecting main and CO metal dusting in the process syngas waste heat boiler respectively. And it elaborates on the material failure mechanism, engineering application and prevention measures. It is considered after the analysis that reasonable material selection, welding, heat treatment and non-destructive testing can prevent or mitigate the above-mentioned material failure to a certain extent.

Key words: steam methane reformer, failure mechanism, stress release crack, high temperature