64 |
Oilfield Technology
December
2014
topsides in the world. The state‑of‑the art topsides was equipped
with a hotel and restaurant to accommodate about 200 personnel,
as well as apparatus for drilling and production capabilities.
With a vertical centre of gravity located 48.3 m above the keel,
the topsides’ stability requirements pushed the limits of the
installation barge – one of only two barges in the world capable
of performing this operation. The bottle‑shaped barge made the
float‑over operation feasible because it satisfied both the stability
and jacket footprint requirements. However, it created challenges
for the mooring arrangement and transportation global strength
needs. The short, fat and heavy jacket also brought challenges to
the launch operation.
Softwaresimulations
The engineering challenges were tackled by numerous analyses and
design iterations based on MOSES and SACS simulations. MOSES is
Bentley’s suite of analysis software for the installation of offshore
structures and the design of all types of floating offshore systems.
SACS is an integrated suite of software for structural analysis and
design of offshore structures, including oil, gas and wind farm
platforms and topsides. The ability of SACS to dynamically iterate
designs allowed the project team to perform advanced analysis,
comply with offshore design criteria and visualise complex results. The
Bentley technology improved
efficiency and accuracy
throughout the duration of the
project. The topsides float‑over
analysis was a time‑consuming
process that required huge
data transfer between SACS
and MOSES. Information such
as structure stiffness and static
reactions were calculated from
the SACS model and passed
to MOSES, which was used to
calculate all the time‑history
hydrodynamic‑related
information such as float‑over
impact force and motions.
All the results obtained from
MOSES were fed back to
SACS to make sure that the
structure was adequate for
all of the load conditions
during the different floatover
stages, which included
stand‑by, entry, mating and
exit. This whole process
had to be updated for each
mooring arrangement for the
bottle‑shape barge feasibility
study, until the optimal
arrangement was selected for
the final design.
Efficientdatatransfer
For the jacket launch analysis,
the jacket was initiallymodelled
in SACS. The jacketmodel was
then converted toMOSES for
launch analysis, which had
an established reputation
World’s heaviest topsides transported and installed on schedule
Dockwise develops solutions for heavy transport and installation (T&I) in the maritime infrastructure
sector using a fleet of 23 semisubmersible vessels and two floating super pallets.
As part of the US$ 1.5 billion SHWE field development project in the Bay of Bengal, Myanmar,
Dockwise set a weight record with installation of the nearly 22 000 t jacket and 30 000 t topsides with
deck support frame for the SHWE platform.
Dockwise performed the engineering design for the T&I contract, as well as provided transportation
and launch operation of the jacket, and transportation and floatover operation of the topsides, as well as
operational support for jacket and topsides load-out. Using MOSES and SACS, Bentley’s offshore platform
analysis, design and installation software, helped to save 5000 man-hours and two operation days during
the project execution.
Alex Rodenburg, Dockwise Senior Project Manager, noted: “The successful SHWE topsides installation
and jacket launch marked a significant milestone for Dockwise. This further validates the company’s
evolution into an offshore contracting partner for the transport and installation of oil and gas platforms.”
Project summary
Organisation
Dockwise Shipping B.V.
Location
Bay of Bengal, Myanmar.
Project objective
Detailed installation design of SHWE platform jacket and topsides.
Load-out, transportation and launch of 22 000 t jacket.
Load-out, transportation and floatover of 30 000 t topsides.
Products used
Products used: MicroStation, MOSES, ProjectWise, SACS.
Fast facts
Dockwise was the T&I contractor selected to install the record-breaking jacket and topsides in terms of
weight.
Bentley’s offshore platform analysis, design and installation software was selected for detailed design.
MicroStation and ProjectWise were used by team members in project offices located in the Netherlands,
USA and China.
ROI
Efficiencies achieved during detail design saved 5000 man-hours of the 30 000 engineering hours.
Simulations conducted using MOSES and SACS cut the estimated topsides floatover time from four days
to two days.
Safety considerations during simulations allowed the installation to be performed without incident.
Figure 1.
SACS andMOSESwere used for engineeringdesignand
installation operations.
