Novel Risk Based Assessment of Pressure Vessels Integrity

Abstract

New methodology for risk based approach to integrity assessment of pressure vessels has been introduced. Namely, the risk matrix has been defined with consequence taken as usual, whereas probability has been separated into two, emphasizing effects of human factor and material defects. Toward this end, the failure assessment diagram (FAD) has been used here as a simple engineering tool to estimate probability of the failure due to material defects. Probability of failure due to human factor has been estimated according to the survey performed (with operators and managers) in the firm where pressure vessel is located and operated. With consequence estimated according to the simple standard procedure or by using more complex procedures (API 581, RIMAP), the novel risk based structural assessment has been completed. As an example, cylindrical storage tanks for compressed air are analysed.