J. Phys. IV France 09 (1999) Pr9-137-Pr9-146
Hydrogen attack in a welded reactorS.M. Schlögl and E. van der Giessen
Delft University of Technology, Koiter Institute Delft, Mekelweg 2, 2628 CD Delft, The Netherlands
Reactors for hydrocracking and hydrotreating are exposed to high hydrogen pressures at elevated temperature. The critical failure mechanism in these vessels is hydrogen attack, i.e. chemically-driven damage accumulation leading to intergranular failure. These rectors are typically manufactured by circumferential welding of forged belts made of 2.25Cr-1Mo steel, and the associated microstructural changes make these weldments especially suspectible to hydrogen attack. This paper summarizes a recently developed model that links the chemistry of hydrogen attack with the mechanical behavior through a damage model. This model is then incorporated into a finite element model and used to calculate the deformation and damage evolution, stress distribution and failure time of a welded reactor under internal hydrogen pressure.
© EDP Sciences 1999