Design check of an S-Lay offshore pipeline launching using numerical methods

The production of oil and gas from offshore oil fields is, nowadays, more and more important. As a result of the increasing demand of oil, and being the shallow water reserves not enough, the industry is pushed forward to develop and exploit more difficult fields in deeper waters. The purpose of this paper is to determine the optimum launching parameters of a subsea pipeline in S-Lay system using the software OffPipe. The offshore pipelines designing is an intricate enterprise following very demanding designing codes since at stake is the integrity of multi-million dollars investments in offshore oil and gas exploitation facilities. The case study of this paper is taken on purpose to show how the numeric analysis may help to detect potential problems that might occur during pipe launching with S-Lay method. In the analysed case the launching process is under control since all the launching parameters and stresses are well below the critical ones. In any event the numeric modelling of the process was demonstrated to be a valuable tool in the design engineer hands in order to assess the feasibility of any launching subsea pipe launching.