CP-8001 Load Chart PDF + Specifications

The Penta-Ocean CP-8001 is a large SEP-type multipurpose crane vessel developed for offshore wind installation, marine foundation work and other heavy offshore construction duties. It was completed in December 2018 and represented an important milestone for Japan’s offshore wind industry as the first domestically owned SEP vessel fitted with a large fully revolving crane.

The vessel was designed to combine the stability of a jack-up platform with the lifting flexibility of a revolving heavy-lift crane. By raising the hull clear of the water, CP-8001 can reduce the influence of waves during lifting, improving safety, working accuracy and operational availability in difficult offshore conditions.

Design and Construction

The basic vessel design is the GustoMSC GJ-3750C. GustoMSC also supplied the hydraulic jacking system, while the main crane was supplied by Huisman.

The vessel measures approximately 73 m in length between perpendiculars, 40 m in beam and 6.5 m in depth, with a full-load draught of about 4.35 m. The main deck provides approximately 1,750 m² of working area, allowing the vessel to carry construction equipment, foundation components and wind turbine installation materials.

International gross tonnage is approximately 7,456 GT, and the vessel can accommodate up to 120 people. A helideck is also fitted to support offshore crew transfer and project logistics.

Main Crane

CP-8001 is equipped with a fully revolving Huisman pedestal crane with a maximum rated lifting capacity of 800 tonnes at a 26 m working radius.

Its load-radius performance includes approximately:

• 800 tonnes at 26 m
• 600 tonnes at 35 m
• 400 tonnes at 48 m
• 200 tonnes at 76 m

This gives the crane relatively strong capacity at longer radii compared with conventional harbour or construction cranes, which is important when handling offshore wind components, foundation structures and large marine equipment from the deck of a jack-up vessel.

Jack-Up System

The vessel is equipped with four jack-up legs and a GustoMSC continuous hydraulic jacking system.

Standard leg length is approximately 66.7 m, while the design allows installation of legs up to about 86 m long. The standard configuration supports jack-up work in water depths of around 30 m, while the long-leg configuration can extend this capability to approximately 50 m.

Each leg has a jacking capacity of approximately 2,400 tonnes. The continuous hydraulic jacking system can raise or lower the vessel at around 0.4 m/min, while leg handling speed is approximately 0.6–0.67 m/min.

Spudcans are fitted to the leg bottoms, and a jetting system is provided to assist with seabed penetration and leg extraction.

Dynamic Positioning and Thrusters

Before the vessel is elevated, precise positioning is handled by a ClassNK DPS-B dynamic positioning system.

CP-8001 uses four azimuth thrusters, with one positioned on each side at the bow and stern. The system is designed with redundancy so that loss of one thruster, control unit or power source does not immediately result in loss of station-keeping capability.

This positioning capability is particularly useful when aligning the vessel accurately over turbine foundations or other offshore structures before the jack-up legs are lowered.

Offshore Wind Capability

One of the principal reasons for developing CP-8001 was the expansion of Japan’s offshore wind sector.

The combination of an 800-tonne revolving crane, jack-up stability and relatively large working deck gives the vessel the capability to install or remove large offshore wind components and marine foundations. Penta-Ocean has stated that the vessel is capable of handling installation work associated with 10 MW-class wind turbines.

Marine Construction Applications

In addition to wind turbine work, CP-8001 can be used for installation of large offshore structures and subsea foundations.

The 800-tonne revolving crane and jack-up arrangement allow the vessel to perform heavy lifting from a fixed elevated position rather than from a freely floating hull. This is particularly useful for pile installation, jacket structures, large marine modules and other work where precise load placement is required.

CP-8001 can also work together with Penta-Ocean’s self-propelled multipurpose crane vessel CP-5001, allowing transport and installation activities to be divided between vessels for more efficient marine construction operations.

Early Offshore Wind Work

One of CP-8001’s early significant assignments involved the removal of the 2 MW offshore wind turbine and observation tower off Kitakyushu, originally installed as part of a J-Power/NEDO research project.

Penta-Ocean announced the use of CP-8001 for this removal work in 2019, demonstrating the vessel’s ability to handle both installation and decommissioning-related offshore wind activities.

Relationship to CP-16001

CP-8001 became the foundation for Penta-Ocean’s later investment in larger offshore wind installation vessels.

Experience gained from building and operating CP-8001 contributed directly to the development of the much larger CP-16001, equipped with a 1,600-tonne crane. Penta-Ocean specifically cited its shipbuilding and operational experience with CP-8001 when planning its second SEP vessel.

Overall Assessment

The Penta-Ocean CP-8001 is best described as an 800-tonne self-elevating crane vessel / offshore installation vessel designed for offshore wind and heavy marine construction.

Its combination of a Huisman 800-tonne revolving crane, four jack-up legs, GustoMSC continuous hydraulic jacking system, DPS-B positioning, 1,750 m² deck and up to 50 m water-depth capability made it a significant step in the development of Japan’s domestic offshore wind construction fleet.