9 - Thermal Expansion Design

Abstract

Thermal expansion of pipeline may be induced, because the temperature and pressure of production in pipeline are normally higher than the ambient condition. The thermal expansion of pipelines is one of the most important issues in the design and operation of the subsea pipeline system, for example, tie-in design, lateral and upheaval buckling, axial walking and fatigue, free spans, and pipeline crossing. The thermal expansion of the pipeline depends on the temperature and pressure profiles along pipeline, pipeline submerged weight, and axial friction force. The analytical solutions of stress and strain distributions along the pipeline under different load conditions are given. Effective axial forces of pipelines, which is a very important concept in subsea pipeline engineering, are defined and calculated under different conditions. Finally, examples of thermal expansion calculations for single pipeline and PIP are given and discussed.