Submarines used for civil services subsea offer so many advantages that they have the potential to replace the present multipurpose support vessels (MSV) and initiate a new era of support vessels, the submersible support vessels (SSV). The latest developments in submarine components show that the SSV is a safe, economic and comfortable system As described in other contributions, the submarines can be used for a variety of tasks and offer many operational advantages such as performance of work on the spot and independence of weather and also economical advantages such as low-cost operation, time-saving operation and high availability The technology developed by Thyssen Nordseewerke will achieve a reliable SSV Combined with the operational technology developed by NORSUB. this will revolutionize the subsea intervention market
The name of the conference expresses what offshore oil and gas production really is-a subsea activity. One may take the view that the development of huge islands for production was the work of ambitious engineers.
In the last few years there has been an escalation of size and costs and economists-forced by market realities-are now trying to reduce production costs. This production cost decrease can be achieved not by cheaper construction but by change of technology. Change of technology in offshore production is concentrated on subsea activities. This started with subsea completions and manifolds and will end with complete subsea production At the end of this development the only activity to be seen at surface could be the struggle to lower down tools in bad weather over distances of 500 m.
But there is a chance to overcome these remaining problems by the introduction of submersible support vessels (SSV), whose operational benefits have been extensively described in other contributions. The vessels under discussion now are to be understood as fully autonomous submarines that do not need any offshore support.
Thyssen Nordseewerke started in 1980 with the development of the first autonomous submarines for multipurpose intervention, the AOS 500–1000 versions. A small boom of designs appeared at that time and disappeared mainly because of technical problems with the key components, e.g. the power supply Thyssen Nordseewerke continued this development with two concepts-OSS and SSS-that are powered by closed-cycle diesel engines. The SSS, so called after the project name Super Subsea System, is chosen as the latest example of SSV evolution in submarine technology.
The main feature of the Super Subsea System concept has been described elsewhere It is its modular system that makes the SSS different from the HCS, MASU and others Thus, the submarine designer has only to consider the interfaces to, for example power supply, work personnel or hardware. The neutrally buoyant modules are designed to be adaptable to these common interfaces.
The submarine designer can prepare an optimal design with respect to trim, buoyancy weight, volume, size and power requirements, whereas the designer of the work modules can look for the best solutions to perform the lob.
The SSS (Fig. 1) comprises a pressure hull and a streamlined outer shell.