Safety calculation of cold-hot oil alternating transportation for crude oil pipeline

By using theoretical calculation model, based on basic parameters, pipe features, soil type, and operation parameters of cold-hot oil alternating transportation, structure analysis under the effect of pipeline temperature and pressure load, static strength check, stability analysis and fatigue life calculation of typical sections of the pipeline are made. Results show that radial stability, axial stability, pipe strength and elbow strength of the pipe all meets operation requirements. The fatigue life of pipeline which contains plane defect and deep-buried defect will shorten as the diameter increases, the pressure changing amplitude increases, and defect depth increases. The results can provide reference to the primary design of cold-hot oil alternating transportation process for crude oil pipelines, and provide a check base to the pipeline's operation safety.