Fall pipe module Simon Stevin ready for departure to Spain

At 4 pm, the fall pipe module for Jan De Nul Group’s mining and fall pipe vessel Simon Stevin was placed on a pontoon to be transported to the La Naval shipyard in Sestao, Spain.

This Monday, 15 June, the pontoon and its tugboat leave for Spain. Approximately 7 days later, after passing through the Scheldt past Antwerp and Vlissingen, through the Channel over the Biscay Gulf to Bilbao, the pontoon will arrive in Sestao, where the 2,000 ton module will be hoisted on board the Simon Stevin by means of the floating crane Rambiz.

This fall pipe module was designed by Jan De Nul Group itself, aided by Vuyk Engineering Rotterdam in The Netherlands. Iemants Staalconstructies in Arendonk built the module. The heart of the installation, namely the ‘motion base’, was built by Jan De Nul on its own account.

Facts & Figures:

  • This module is 40 m long, 24 m wide and 31.5 m high (above the deck of the Simon Stevin), the size of an apartment building consisting of about 70 flats divided over 8 floors;
  • The weight at transport is 2,000 tons;
  • The 2,000 ton module is moved by means of 16 SPMTs (self-propelled modular trailers). 96 axes, with a total of 384 wheels, are needed to move the module;
  • 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 2,000m. 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’.

The mining and fall pipe vessel Simon Stevin and the investment programme of Jan De Nul Group

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 will have 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 begin November 2009.

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 37,500 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 (both under construction) 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 will be the only company in the world that can dredge up to a depth of 155 m.