by Hans | June 23rd, 2010
After waiting some time offshore Hoek van Holland due to the weather situation, the SAIPEM 7000 entered the Waterweg Monday morning bound for the Keppel-Verolme yard in Rotterdam-Botlek
Saipem 7000 is the world’s second largest crane vessel, after the Thialf. The crane radius of the Saipem 7000 grants a lifting capability of 14,000 tonnes at 42 meters while the Thialf can lift 14,200 tonnes at 31.2 meters. It is owned by the oil and gas industry contractor Saipem S.p.A. The Saipem 7000, originally named the Micoperi 7000, was conceived in the mid 1980s by its original owners Micoperi as a multipurpose offshore oil platform installation vessel that would be able to install very large oil production platform decks (known as integrated decks) as well as the decks’ supporting structures (known as jackets) using its two very large fully revolving cranes. It would also be able to support the offshore completion of the platform by providing hotel and workshop facilities for large construction crews. Saturation Diving facilities would support subsea connection work. The vessels size and semi-submersible form would allow it to operate in worse weather conditions than smaller and conventionally shaped vessels.
The huge cost of a vessel of this size would be offset by the cost and time savings made by the oil company as the large integrated decks could be completed, tested and commissioned onshore. Prior to the introduction of the large crane vessels offshore oil platforms were made up of 1000 – 2000 tonne modules which were lifted into place individually by smaller SSCV’s or monohull crane vessels and then connected together offshore, tested and then commissioned, this often took over a year. Other savings in the installation of the jackets could also be made. The vessel was designed by Gusto Engineering during 1984 and was built between 1985 and 1987 by Fincantieri-Cantieri Navali Italiana S.p.A. at their Monfalcone yard, Trieste in north-eastern Italy. The vessel was built in two halves in a long dry dock. The halves were then floated out from the dry dock and mated. During the mating operation the halves were supported by temporary pontoons. The hull mating was complete in early 1987 and the two cranes built by Officine Meccaniche Reggiane under subcontract to American Hoist & Derrick Company (Amhoist) were installed in sections by the Saipem crane vessel Castoro Otto in April of that year. The sea trials, which took two months, started in September, and on 15 December the vessel was handed over to Micoperi.
The cost of the vessel was not released by Micoperi but it was estimated in the technical press as being up to 400 million US dollars. Two fully revolving cranes with 140-metre-long booms fitted with 4 hooks. Each crane is capable of lifting up to 7,000 tonnes at 40 m lift radius using the main hook. The auxiliary hook capacities are 1st Auxiliary 2,500 tonnes at 75 m and 2nd Auxiliary 900 tonne at 115 m. The whip hook has a capacity of 120 tonnes at 140 m. The 2nd Auxiliary hook can be deployed to a water depth of 450 m. Each crane was fitted with 15,600 hp (11,630 kW) engines to power the boom and load hoists, 9 tugger lines and the crane slewing system. The cranes use 48 miles (77 km) of wire rope of various diameters During the winter of 1999-2000 the Saipem 7000 underwent a refit to enhance its positioning and power systems and add a J-lay system. The power system was upgraded to provide up to 70,000 kW using 12 diesel generators. To improve the vessel’s resilience the generators are distributed between four separate engine rooms.
Two 5,500 kW retractable azimuthing thrusters were added, one below the forward part of each hull. The DP system control computers were also replaced. The hull, deck and deck structures were modified to accept the Gusto designed J-lay tower and its support equipment. The J-lay tower can lay pipe from 4″ to 32″ diameter with a tension of up to 525 tonnes (5.15 MN) using the tensioners and up to 2,000 tonnes (20 MN) when using friction clamps. The deck can used to store up to 10,000 tonnes of pipe. To allow space for the increased equipment some items from the original specification were removed, including 2 anchor winches from the bow, all the moon pools, and the boilers used to provide steam for the steam hammers.
The Saipem 7000 set the world offshore lifting record of 12,150 tons for the Sabratha deck in the Mediterranean Sea. A local record for the Gulf of Mexico (Mexican area) was set with the 10,473 tons of the PB-KU-A2 deck. The Saipem 7000 laid the 24″ pipeline for the Blue Stream project between Russia and Turkey up to the record depth of 2,150 meters in the Black Sea. This was broken at the end of 2005 by the Balder which laid a pipeline in 2,200 meters of water.