An offshore platform has several modules that contain much of the equipment needed for oil and gas production, and these are placed on the limited space of the topside, which must be used wisely by taking into account several factors including the efficiency of the equipment, the weight distribution of the modules, and so on. Furthermore, the equipment layout should leave sufficient space in between to ensure operability, maintainability, and safety. The proper arrangement of the offshore topside is subjected to many requirements, including those mandated by international codes and standards. The design problem to arrange the topside of an offshore platform can be difficult to solve due to the number of modules and equipment placed on the topside. Furthermore, the arrangement depends heavily on knowledge and experience from experts and from previous projects.
This study proposes a method to arrange the offshore topside based on an expert system and multistage optimization in order to obtain the optimal arrangement that addresses various considerations and satisfies the given requirements. The proposed method consists of four components. First, an expert system is proposed to systematically computerize experts' knowledge and experience and to evaluate the feasibility of alternatives for the arrangement of the offshore topside. This system expands on the results of a previous study where authors presented the arrangement design of a submarine. Second, a multi-stage optimization method is proposed to yield a better arrangement design by formulating the arrangement design problem as an optimization problem with two stages. Third, an arrangement template model (ATM) was proposed to store the arrangement data of the offshore topside, and the data stored in the ATM was used to express the expert knowledge or the corresponding variables of the optimization problem. Fourth, the user interface was developed to run the expert system and for optimization. A prototype program was then developed to solve an FPSO topside problem in order to evaluate the applicability of the proposed method. The results showed that the proposed method can be used to obtain the optimal arrangement of an offshore topside.