Simon Stevin into service

The mining and fallpipe vessel Simon Stevin left this morning around 11:00 to Australia for its first 2 rock dumping projects: the free span correction on the Pluto pipeline in 80 meter water depth on the one hand, and the construction of a pipeline crossing for the Reindeer pipeline over the Pluto pipeline on the other. The Simon Stevin will load the required rock on its way to Australia, and due to its size, a large advantage is that the full load of 33,500 tons is just sufficient to execute both projects without reloading. 
The Simon Stevin was delivered last Thursday, 4 February, to its owner Dredging and Maritime Management S.A., subsidiary of Jan De Nul Group. The keel laying of this vessel took place on 30 April 2008 and the launching was celebrated on 13 March 2009. The vessel was built by the shipyard Construcciones Navales del Norte in Sestao, near Bilbao, in Spain. The vessel is by far the largest of its kind and can work down to 2000 m water depth.

Mining and Fallpipe Vessel Simon Stevin

The ambitious investment programme 2007-2011 is in full progress. In total, more than 1.8 billion € will be invested in the new construction programme. By doing so, Jan De Nul Group has at its disposal the largest and most modern dredging fleet in the world, including the fall pipe vessel Simon Stevin, suitable to execute the most complex dredging works by 2010. The 191 m long vessel will be used for precise rock dumping to a depth of 2,000 m. The system for the unfolding of the fall pipe is extremely advanced and operates fully automatically. At the bottom of the fall pipe there is an ROV (Remote Operated Vehicle) that accurately corrects the position of the lower end of the fall pipe. The vessel has a 33,500 tons loading capacity and makes it possible to dump 2,000 tons of rock per hour at a depth of 2,000 m. The vessel can accommodate 70 persons. 
The fall pipe vessel Simon Stevin will mostly be deployed in the offshore industry in which oil and gas pipes have to be installed at large depths: the Simon Stevin can level the seabed and dump rock up to a depth of 2,000 m. The fall pipe can process boulders with a diameter up to 400 mm, which is more than any other fall pipe vessel on the market. This vessel is being built by the shipbuilding yard 'La Naval' in Sestao (Bilbao, Spain) and will be brought into operation at the end of 2009.

Deadweight 36,000 tons
Length 191.5 m
Breadth 40.0 m
Draught loaded 8.5 m
Propulsion power 4 x 3,350 kW
Bow thruster power 4 x 2,000 kW
Total installed diesel power 24,350 kW
Rock storage capacity 19,500 m³
Speed 15.5 kn
Accommodation 70
Dynamic positioning DYNAPOS AM/AT R Class2
Fall pipe  
Maximum dumping depth 2,000 m
Maximum dumping capacity 2,000 tons/hr
Fall pipe diameter 1,000 mm
Rock size D100 max 400 mm














A few interesting facts and numbers regarding the fall pipe vessel Simon Stevin

  • The Simon Stevin is the largest sailing fall pipe vessel in the world with a capacity of 33,500 tons. This is 25% larger than the 2nd in row, the ‘Nordness‘ with a capacity of 25,960 tons. 33,500 tons is enough to provide the Grand Place in Brussels for at least 20 times with new cobble stones.
  • The Simon Stevin is the first ‘purpose built’ fall pipe vessel. From day 1 the design was optimized to work at great depths.
  • In order to install the rocks with great accuracy, the pipe is attached below the vessel until right above the seabed, up to a depth of 2,000 m. That is as deep as 6x the Eiffel tower. The fall pipe can be built in 6 hours and, after dumping, can be dismantled in six hours and taken on board of the vessel. To facilitate this, Jan De Nul Group designed a new installation method that is fully automated and that works independently from the vessel movements at sea. The heart of the installation, the so called ‘motion base’ is manufactured by Jan De Nul Group itself.
  • The bottom of the fall pipe is operated by an unmanned submarine, Remote Operated Vehicle (ROV), that can work at depths up to 2,000 m. A ‘common’ manned submarine cannot go deeper than 250m.
  • The vessel is equipped with a second ROV for survey and other interventions. This can be operated completely independently.
  • The rocks are dumped at 2,000 tons per hour which equals 100 trucks per hour or 1 full truck every 36 seconds.
  • The total engine power amounts to more than 25,000 kW, enough to provide a city of 130,000 inhabitants with electricity to do the housekeeping.
  • The distance between the keel and the bridge equals the height of a church. However, a lift on the vessel makes life a lot easier.
  • The accommodation on the vessel for more than 70 persons can easily compete with four star hotels. For instance, every day 35 m³ - or 3 tankers - of drinking water is produced out of seawater. The same water is being purified on board after which it can flow back into the sea.
  • The vessel has its own helicopter landing platform that is suitable for most types of helicopters such as the well-known Seaking from the popular Flemish TV series and movie “Windkracht 10”.
  • The fall-pipe module was built in Belgium and was hoisted on board in one go. The 2,000 ton heavy module is as large as an apartment complex with 70 apartments divided over 8 floors.

Simon Stevin in the Offshore Industry

New oil and gas fields that are difficult to exploit are being sought for because of the energy shortage. Consequently the demand for specialized equipment continues to rise. The planned fleet expansion is therefore especially concentrated on the offshore capacity. With the construction of the 33,500 tons fall pipe vessel Simon Stevin and the 6,000 tons stone dumper Willem De Vlamingh (under construction) and the conversion of the 4,600 tons La Boudeuse into fall pipe vessel Jan De Nul Group reinforces its position and enters the niche market of the offshore rock works. Although it was not a priority in the past, Jan De Nul Group wishes to meet the demand of the oil industry for a ‘single contractor concept’ in which one company is responsible for the design and execution of all related maritime works such as dredging, rock works and civil constructions. The two new 46,000 m³ trailing suction hopper dredgers Cristóbal Colón and Leiv Eiriksson are not only unique when dredging capacity is concerned, but also when it comes to dredging depth. With these new vessels Jan De Nul Group is the only company in the world that can dredge up to a depth of 155 m.