A Study on Quasi-periodic Operating Temperature for Buried Hot Oil Pipelines

The oil temperature along the buried hot oil pipelines is influenced by operating schedule. The soil temperature outside the pipelines varies as quasi-periodic law under the affection of air temperature above the ground and oil temperature in it. The formula of periodic operating temperature along it is given and the influence on periodic operating temperature by transporting schedule is discussed in this paper. According to this research results, when allowable shutdown time needs to be determined under the oil pipeline failure, it is necessary to take the variations of operating parameters in it before shutdown into account.