The Agency of Industrial Science and Technology (AIST) of the Ministry of International Trade and Industry (MITI) started a research project of a subsea production system in 1978 and finished it in 1984. The target of the project is to design a prototype of the subsea production system that can be used at depths of 300 m to a maximum of 900 m. A pre-prototype of the system was tested in 50 m of water in the Seto Inland Sea during a period of about nine months from 1983 through 1984. Most of the system functioned properly as expected. The system comprises five subsystems: total, wellhead, pipeline, manifold and riser-storage. AIST administrated the project and gave financial supports to the Mechanical Engineering Laboratory of AIST and the Technology Research Association of Subsea Production System.
The Japanese Government has a policy to improve off shore oil development technologies in general. Several offshore oil and gas fields are developed in Japan. In 1984, gas production began from a platform built in 150 m of water. A wildcat well was drilled in 470 m of water by a semisubmersible rig. Considering these trends in advance, AIST started the national project of SUBSEA PRODUCTION SYSTEM in 1978, and completed it in 1984. The Mechanical Engineering Laboratory and the Technology Research Association of Subsea Production System organized by eighteen Japanese companies have carried out this project. The organization of the project is shown in Figure 1, and the project schedule is indicated in Figure 2. An offshore pilot test was conducted successfully in 50 m of water in the Seto Inland Sea near Hiroshima for about nine months from 1983 through 1984. The test confirmed operation-capabilities of equipment. The detail design of the system has been completed as a result of the test.
The system comprises five subsystems: total, wellhead, pipeline, manifold and riser-storage. The This paper discusses the system, in general terms, description to results of-the offshore pilot test. More detailed discussions of some subsystems are provided by three companion papers on the system, which are also being presented at this conference: wellhead (OTC 4958), reentry (OTC 4959) and production riser (OTC 5011) systems, respectively.
The target of the project is to design a subsea production system that can be used at depths of 300 m to a maximum of 900 m in Japanese environment. In the sea areas surrounding our country, fishery is quite active. The system has to coexist with fishing operations. Sizes of Japanese oil fields usually rank as medium or marginal ones. The basic concept of the design is chosen by considering the abovementioned conditions.
All the systems put on the seabed should be installed and/or retrieved by guide lineless and diver1ess methods.
The TFL system may be made use of to maintain well bores.
The system should be adapted for casing and tubing hangers established in the industry.
