Failure analysis of an old oil pipeline

Following the collapse of a section of a steel oil pipeline during its return to service after maintenance work, an analysis was made of the section itself and its fracture site. Chemical examination showed that the steel was too sensitive to brittle fracture and not suitable for this application. Investigation of the crack showed that the collapse was caused by a pressure surge which resulted in a brittle fracture at an already defective point. The question of the environmental safety of this pipeline and whether it could be improved is also discussed.