HANDLING OF HEAVY INTEGRATED DECKS AT SEA [STEP 1]

Objectif

To demonstrate the technical viability of new equipment and associated method for the safe and stockless installation of heavy integrated decks onto offshore platform and to install or to remove large size offshore packages.
The method calls for the usage of conventional cargo barges available on the market, thus eliminating the need for Heavy Lift Vessel (HLV).
The method applies also for installation of decks which weight is beyond the capacity of existing HLV.
Thus, the proposed method is cost effective.
The project includes 2 steps :
- STEP 1 : Model basin testing and building of a prototype (1994-1995)
- Object of the Contract OG./00287/94/FR
- STEP 2 : Tests at sea (1996-1997).
PROTOTYPE TESTS
All the sequences and phases were satisfactorily run, and the prototype behaved as expected. All the Smart Leg functions were properly achieved, especially the transient phase between the touchdown and the free heave.
It was confirmed that this mating process is shockless, without the need of external energy.
NUMERICAL MODELLING AND PHYSICAL BASIN TESTS
Software design, testing, simulations and additional enhancements to the programme were completed and ended by 22/12/95. The programme is fully operational. The tests have proved the operability of the Smart Leg system, and have demonstrated the accuracy of the software by confirmation of the predicted results.
CONCLUSION
Both prototype tests and tank tests show that the technical options and the numerical modelling give considerable confidence in the full scale SMART LEG system.
This project gave ETPM :
- a reliable and validated numerical tool to perform calculations on SMART LEG studies,
- a further theoretical and operational knowledge of the SMART LEG system.
1. INNOVATIVE TECHNOLOGY
Smart Leg cancels shocks while other methods intend absorbing them.
The method allow for the shockless transfer of the load from the conventional cargo barge to the offshore supporting structure (jacket) using hydraulic chambers driven with a check-valve. The control of the check-valve is based on the real time analysis of loads and relative motions.
The proposed equipment is simple, energy-free, reliable and safe.
2. THE CONTEXT IN WHICH THE TECHNOLOGY IS OPERATING
This new technology will operate in the offshore platforms installation market. Potential users are the oil and gas companies operating offshore. The competitors are of a limited number and the competition is very keen and active. Thus, it is essential to develop new methods and equipments in order to reduce operation costs and to remain competitive.
The weight of the decks contemplated is in the range 4000/20000 tons or even more, which covers a large part of the market.
3. ECONOMIC ASPECTS
The method proposes drastic reduction of costs for installation of offshore platforms together with enhanced safety. Saving apply on installation itself as Heavy Lift Vessels are no longer required Marine installation spread will consist of cargo barge and tugs much cheaper to mobilize and operate than the HLV.
Saving apply also on the hook-up costs as the heavy decks can be installed in one single piece only, thus eliminating the work for the interconnection of the various modules (hook-up).

Programme(s)

ENG-THERMIE 1 - Programme (EEC) for the promotion of energy technology in Europe (THERMIE), 1990-1994

Thème(s)

5.3 - ENVIRONMENTAL INFLUENCE

Appel à propositions

Data not available

Régime de financement

DEM - Demonstration contracts

Coordinateur

ETPM SA

Contribution de l’UE

Aucune donnée

Adresse

AVENUE PABLO PICASSO 32 TSA 76001
92754 Nanterre
France

Coût total