Jackup barge set for service off Saudi Arabia

Offshore staff

SCHIEDAM, the Netherlands -- Aramco Overseas has taken delivery of the new heavy-lift jackup barge ARB-3 from Jurong Shipyard in Singapore.

According to GustoMSC, which supported Saudi Aramco with the design, the barge was due to start operations offshore Saudi Arabia before year-end.

An article in GustoMSC’s latest Inside newsletter describes how in 2003, Aramco asked GustoMSC to perform design studies for a self-propelled installation and maintenance vessel.

This was followed by design of a heavy-lift jackup barge in 2006, with Aramco providing the design specifications based on its experiences with offshore maintenance in its fields.

The barge has a hull measuring 110 x 42.5 x 9 m (361 x 139 x 29 ft), with a leg length of 95.3-m (312 ft), and can operate in water depths of 5-60 m (16-197 ft). It incorporates a 550-ton heavy-lift offshore crane, pipeline repair equipment, and a variable load capacity of 2,500 tons.

To improve deck layout efficiency, the crane is positioned on the centreline, just aft of the deckhouse, allowing an unobstructed tail swing. This way, the full free deck area can be overseen, with no danger of swinging heavy lifts over the accommodation area, which houses 119 personnel.

Additional lifting is provided by four 30-ton knuckle boom cranes positioned over the jacking structures. On the starboard side are six 50-ton pipeline davits with a 3-m (9.8-ft) outreach – in a floating condition, the barge will be able to perform pipeline repairs while being held in place via a four-point, 2.5-in. (6.3-cm) wire mooring system. Within this spread, the barge can be relocated over distances up to 200 m (656 ft).

Aramco signed the construction contract in December 2006, and Jurong Shipyard later commissioned GustoMSC to supply the GCC-550 electrically driven heavy-lift crane. The main hoist is split into two blocks of 275 tons, available for combined and separate operations. Load tests were performed in Singapore in August.

GustoMSC also supplied the GLL-80/6 rack and pinion jacking system, driven by electric motors with variable-speed drives. The latter allow step-less speed control. Loads are distributed equally over the drives, which facilitates smooth control of jacking operations.

12/31/2010