Damen Shipyards Group has announced a new line of Trailing Suction Hopper Dredgers (TSHD). The new product range comprises the Marine Aggregate Dredger (MAD) 4000 and 5600 vessels.
The MAD 4000 and 5600 vessels have been designed in collaboration with Maritime Design and Engineering Services (MD&ES) and are said to follow an increase in demand for civil construction supplies deriving from an overall improving economy.
North Sea Conditions
For offshore aggregate operations, the new vessels will be able to work in North Sea conditions up to depths of 60 metres. This allows for mining of sand and gravel in deeper waters, farther from shore than preceding models. The vessels feature Tier III engines and do not require ballast water.
Unlike traditional dredgers, the bow shape of the MAD vessels allows them to operate in adverse weather conditions. The shape is based on a Damen design applied to vessels such as the Damen Offshore Carrier (DOC) and Platform Supply Vessel (PSV). In addition to improved seakeeping behaviour, the bow shape also protects the sand and gravel cargo from green water ingress.
Dredging Equipment
A submerged, wear-resistant Damen dredge pump facilitates the loading of sand and gravel aboard. The aggregate then passes through heavy-duty dredgers’ screening towers, where giant sieves allow for a better assessment and classification of the mined material.
Following this, it is stored and de-watered in the vessel’s hopper – with a capacity of either 4000 or 5600 m3. The operation is supported by optimised instrumentation, offering feedback throughout the entire process.
Upon arrival to port, the vessels’ fully automated clamshell system unloads the material onto a conveyer belt. The flexible system is suitable for use in varying locations.
Standardised and Customised
The design is standardised, but can also be customised. For instance, the vessel can be supplied with bottom doors to offer additional versatility in case it is required to perform differing operations. It can also receive spud poles and the MAD 4000 can easily be converted into a MAD 5600.
