Ocean Dynamics LLC :: Projects

Liwan 3-1 3rd Party Verification

Liwan 3-1 3rd Party Verification: Jacket Design and Float-Over Installation

• Timeline: 2010
• Location: South China Sea
• Water Depth: 200m
• Operator: CNOOC
• Client: COOEC

Project Description:
Liwan 3-1 is China’s first deepwater project with an estimated contingent reserves of between 4 trillion and 6 trillion cubic feet of gas. While the deepwater depths approach 1500m, the Central Processing Facility sits in 200m depth and is connected to the field via a 100km subsea pipeline. It is estimated that the jacket is the largest single piece jacket.

ODL Scope of Work:
ODL was contracted to complete a 3rd party verification of the basic design of the Liwan 3-1 jacket and to design the float-over installation of the Central Processing Facility.

Key Details:
ODL reduced the jacket weight by 6,000mt creating a significant cost savings on steel tonnage and construction costs for CNOOC.
The outside diameter of the piling is of the largest in the world at 108 inches.
The topsides transportation weight of 27,000mt is one of top 5 heaviest transports in the world. The not to exceed in-place topsides weight is 40,000mt.
The jacket is the third largest single piece jacket in the world at 32,000mt. It is the largest conventional steel jacket outside the Gulf of Mexico.
ODL will complete an evaluation on the HYSY229 barge to re-configure the dimensions of the barge.