Abstract
On June 5, 2009, there was an oil leakage failure accident from an above ground oil storage tank in a large oil depot. The pump of the tank was broken, therefore, the oil contained in the pipeline leaked. The leaked oil amounted to 35, 000L.
The authors have investigated the tank, the pump and the pipeline to find the cause of the accident and to suggest a preventive measure against same kind of accidents. Some important issues of the investigation are fractography examination of a part on which failure occurred, strength of the pump and a type of load and its magnitude which produced during the operation. As a result, the authors have found that the accident was caused because of an excessive internal pressure rise in the pipeline because the pressure relief valve had been removed from the tank due to an improper piping work. Also the authors have estimated that the internal pressure could reach up to 5. 49MPa, and then the pressure caused the brittle fracture of the pump casing.
