Application of the ZIGZAG Concept to a Heated Pipeline in the Soft Soil of the Guanabara Bay

In January 2000, a buckling caused by a thermal expansion of a pipeline in the Guanabara Bay/Rio de Janeiro led to the rupture of a 16” pipeline to the leakage of heavy heated MF380 oil into the bay area. In order to avoid such undesired incident, PETROBRAS has carried out research looking for solutions for a new pipeline. As a result the concept of a pipeline with “ZIGZAG” geometry was introduced. There are very few examples of oil industries that apply this concept, especially with the soil conditions of the Guanabara Bay. Several studies were carried out to verify the thermal stability of this new pipeline structure. This paper presents a comparison between the conventional single pipeline and the ZIGZAG pipeline.