Objective
This project consists of testing in a significant water depth and without the intervention of divers, a remote controlled modular system for the preparation of pipeline extremities in view of a subsequent connection.
The object of the project is to validate one of the main phases of a complete subsea pipeline repair operation, an efficient preparation of pipe extremities being indispensable whatever the considered connection method.
The connection itself is not included in this project.
The main two objectives of the programme have been completely achieved, these objectives being the proof that the pipe extremily preparation module is efficient, and that the remote controlled and guideline less handling, positioning and recovery of heavy loads in deep waters is possible. The general structure of the system is reliable inspite of the small modifications to be made.
Moreover, the concept of handling without guidelines with the aid of a transfer vehicle is well mastered and opens a field of important tasks in significant depths.
From the commercialization standpoint, it must be noted that the RMP equipment is aimed at repairing deep see pipelines, operations which fortunately occur seldom. Consequently, the overall programme must be considered as a guarantee, like for instance when a fault is detected on a deep sea pipeline, the technology exists and the problem can be solved.
The commercialization of the RMP system may thus be envisaged in the form of a club of operators using deep sea pipelines. A multidiameter RMP system would be kept operational by this club. This alternative presents the advantage of sharing the important costs linked of the manufacture and maintenance of such a system. The risk would thus be shared between these companies by the intermediate of the club which would operates as an insurance company.
Nevertheless, no deep sea development (down till 1000 m) has yet been achieved. There is no deep sea pipeline market; there exists only one pipeline beyond a 300 m depth in the straits of Sicily. On the other hand, developments in intermediate depths between 300 and 500 m are envisaged (North Sea, Gulf of Mexico, California).
The nearest potential market thus exists at this level. It will require the achievement of additional studies so to propose a complete repair, the connection being done either by mechanical connector, or by hyperbaric welding. Indeed, for these depths, one may envisage the intervention of divers, but only for tasks such as welding.
The following means have been implemented to run this test:
- a pipeline section (layed for this purpose) of about 100 m formed by pipes of 610 mm (24" external diameter) and 25 mm (1") thick in API 5L x 65 steel. This pipeline was lined with coal pitch. Inside this pipe some deposits simulated the pipe dirt.
- a dynamic positioning surface support of the "SEACOM" type : approximately 2500 tjb with a lifting capacity of 70 t minimum in single line and 500 m2 of available deck surface.
- an assistance ship
- a submersible aimed at operating the RMP H-frame, ensuring backup functions and adequate observations.
- an acoustic signalling system allowing to spot the equipment on the seafloor
- the RMP devices : manufactured and tested in shallow waters within the scope of contract 09019/79 i.e. :
- a transfer vehicle to handle and position the equipment (H-frame, table + girder + module assembly) and transmit the required energy.
- a H-frame, monitored by the transfer vehicle or the submersible, allowing to adjust the position of the pipe section and hold it during the operation.
- a worktable to maintain the pipe extremely in position during the operation of modules, also serving a support for the girder
- a module carrying girder which mates onto the worktable equipped with a module carrying trolley serving as guide to the different modules during their operation.
- 3 work modules : external brushing, fine cutting, internal brushing.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
92500 Rueil Malmaison
France