Stress assisted corrosion (SAC) is a major concern for kraft recovery boilers in the pulp and paper industry. A water leak can cause a smelt-water explosion in the boiler. A number of carbon steel tubes showed a deep decarburized layer on the inner surface (water-touched) and also an unusually large grain size at the inner tube surface.
Failure analysis methodology is applied to the principal mechanisms by which boiler tubes fail during service. sThe failure analysis procedure, or methodology for evaluation, is provided in a step by step approach. Among the case histories discussed are: fatigue, erosion, short-term overheating, and hydrogen damage.