Petronas Yetagun FSO Replacement Project

MOS Engineering Pte. Ltd has successfully assisted Bluewater Asia Pacific Group (BWAPG) and Adidaya Energi Mandiri (AEM) on the Yetagun FSO Replacement Project for Petronas Carigali Myanmar (Hong Kong) Limited (PCML).  

The Yetagun Floating Storage Offshore (FSO) was stationed within the Yetagun Gas and Condensate Field, which straddles the blocks M-12, M-13 and M-14 in the Gulf of Martaban, Andaman Sea, covering an area of approximately 24,130km².

The Yetagun Gas and Condensate Field is approximately 230km (125 nautical miles) off the Myanmar coast, in the Taninthayi offshore area, and resides in 105m water depth. 

The Yetagun FSO mooring configuration was a turret mounted nine (9) point 80mm studless chain type mooring.  There were three (3) clusters of three (3) chains with each chain cluster arranged at 120 degree offsets.  The mooring system contained the following components, from the pile to the vessel connection:

  • Nine (9) Suction Piles;
  • Nine (9) Ø80mm Mooring Chain Legs ≈ 752m each

The scope included the disconnection of the nine catenary anchor leg mooring chains of the Yetagun FSO, disconnection of the 16” x 280m export (floating) hose, and the disconnection of the flexible 6” riser.  

The installation of the Yet Sena FSO (formally Bratasena) and Single Point Mooring (SPM) utilised the same assets to pick up, install and tension the chains around the mooring.  

The entire operation from disconnection of the Yetagun FSO to completion of the installation of the Yet Sena FSO and SPM was completed without incident or injury.

 

PARTICULARS                YETAGUN FSO                     YET SENA FSO

Length Overall (LOA)               245m                                                 180m

Breadth                                      42m                                                   31m

Lightship Weight                       17,395Te                                           12,193Te

Dead Weight Tonnage               81,000Te                                           45,789Te

Cargo Tank Capacity                 99,244m3 (624,226 bbls)                  53,324m3 (335,398 bbls) 

Number of Risers                      1 x 6” Production                               1 x 6” Production

Max. Throughput                     16,000bbls oil per day

Mooring                                    Cantilevered Turret                            Single Point Mooring

                                                  9 x Catenary Mooring Chains           9 x Catenary Mooring Chains

Bumi Armada 1203Te Riser Turret Removal

MOS Engineering Pte. Ltd was contracted by Armada Balnaves Pte Ltd, a subsidiary of Bumi Armada Berhad to remove the 1203Te Balnaves Riser Turret Mooring (RTM) from Australian waters prior to cyclone season and transport the RTM to Singapore.  

The RTM was moored within the port area off the coast of Dampier, Western Australia where MOS Engineering towed the RTM from the mooring to the anchorage, where the Heavy Lift Vessel (HLV) MV Jumbo Javelin connected the dedicated sling set around the RTM central column with the assistance of the MOS Engineering diving contractor.  The RTM was lifted onto the main deck of the HLV using the dual 900Te vessel cranes.

Discharging operations were conducted in Jurong, Singapore, where the RTM was lifted off the HLV and transported to the laydown area using 2 x 32 axle Self-Propelled Modular Transporters (SPMT).  The riser was transported to the laydown area and jacked down onto 11 dedicated cradles. 

MOS Engineering completed the scope with well-coordinated project planning, managing a number of teams which allowed a smooth transition for a project that could not be stopped midway as it involved a number of sub-contractors.

The entire operation from disconnection of the RTM off the mooring in Dampier, Western Australia to jack down at the laydown area in Singapore was completed on schedule and without incident.

 

Riser Particulars:

Length Overall (LOA)   97.762m

Body Diameter              Varies 4.0-8.0m

Max Deck Diameter     11.73m

As-Left Weight              1203.5Te

Lightship Weight           996.9Te