Construction barges taking shape in Abu Dhabi (OE 2009)

Sept. 10, 2009
The hull for the first of two new self-propelled jack-up barges has arrived today at Gulf Marine Services' yard in Abu Dhabi, said Commercial Manager Mark Preston at Offshore Europe.

Offshore staff

ABERDEEN, UK-- The hull for the first of two new self-propelled jackup barges has arrived today at Gulf Marine Services' yard in Abu Dhabi, said Commercial Manager Mark Preston at Offshore Europe.

Sainty Marine in China has built the steel hulls for both the GMS Endurance and the GMS Endeavour. The second hull is currently under tow in Hong Kong, and should be delivered to Abu Dhabi in the next three weeks.

Gulf Marine Services (GMS) is assembling the decks, topsides and equipment, and 150-man accommodation blocks. The barges are already being marketed to support operations in the North Sea, Middle East, and West Africa. Both vessels are based on the new Gusto MSC 2500 design.

GMS', which was formed in the 1970s, currently has two K-class accommodation/jack-up barges working in waters off the UAE for the ExxonMobil/ADNOC joint venture Zadco and for the BP/Total/ADNOC Adma-Opco joint venture. Another two are under long-term contracts to Occidental off Qatar.

The K-class barges are limited to operations in 45 m (148 ft) water depth, and can currently cater for 70% of fields in the Arabian Gulf, says Preston. However, the Gusto 2500 design is suited to depths up to 65 m (213 ft). This will allow GMS to pitch the two new barges for forthcoming major projects offshore Saudi Arabia and Qatar.

In the North Sea, the company is hoping to secure one-two year contracts in support of ongoing field operations in the southern gas basin.

As with the K-class, the new vessels feature four legs to speed up jacking operations once on station. However, the legs are of a lattice construction (as opposed to the tubular legs of the K-class vessels), which is better suited to deeper water service. The complex construction means that assembly has to be supervised by a specialist supplier, in this case US company Beacon, which supplied the chords for the jacking system.

Other advantages of the new vessels, according to Preston, are a larger available deck space (around 1,000 sq m), and a much larger deck load of around 1,200 metric tons (1,323 tons), twice that of the existing vessels. Both have a 30-year design life.

The Gusto MSC 2000 jackup vessels are driven by a new-concept diesel-electric, low-loss propulsion system supplied by Wartsila. "The new system uses four azimuthing thrusters linked to a Kongsberg DP2 system," Preston adds, "as opposed to two azimuth and two tunnel thrusters for the K-class barges, which are not dynamically positioned."

The pedestal of the crane is designed to accommodate lifts if required of up to 300 metric tons (331 tons), but more normal loads will likely be 167 metric tons (184 tons) maximum. This should be sufficient for deployment of most shallow waters subsea structures, Preston says. 

Beyond these two, he adds, GMS is looking to build two further look-alike Gusto MSC 2500s. "We will move ahead with this as soon as we secure contracts for the first two units."

When the yard in Abu Dhabi is less busy, GMS undertakes construction for other offshore contractors. One recently completed job involved converting the pipelay barge Stealth for Australian contractor Leighton International. The scope included fitting a new pre-fabricated 280-man accommodation block, a new bow section, and re-arrangement of the pipelay spread. The vessel has since re-deployed to a contract offshore western India.

09/10/2009