Existing dredger revitalized with Damen dredging gear for challenging project


      

The Chinese dredger “Jie Long” has been redesigned by Damen Dredging Equipment to adapt it to cutter dredging at the important depth of -50 m.
This deep dredging is required for its contribution to the infrastructural works of the Macau-Hong Kong-Zhu Hai transport link.
Damen not only engineered and delivered the components, but also supervised the outfitting process.

The “Jie Long” started life as a plain suction dredger, and had been converted long ago in a relatively standard cutter suction dredger.
As the owner, CCCC Guangzhou Dredging Co, has major plans for the “Jie Long”, it required extensive refurbishment.
The plans included dredging at -50m, a task the “Jie Long” could not accomplish in its current state.
The complete refurbishment project was awarded to Damen Dredging Equipment.

Damen first visited the “Jie Long” to asses the state and outfitting of the dredger.
As a result, the engineering could start to design new customized ladder hinge points in the fore pontoons.
Furthermore a completely new ladder arrangement was designed, which included a submerged dredge pump and a cutter unit.
The Damen dredge pump, type OBP4035, is based half-way the ladder.
It is electrically driven by a 500 kW electric motor at 600 rpm, and directly coupled - without gear box.
The hydraulically driven cutter unit is the standard cutter unit of the CSD450.

The “Jie Long” will dredge at an impressive -50 m with its cutter unit.
This significant dredging depth is required for its contribution to an infrastructural project which is pushing the technical boundaries : the Macau-Hong Kong-Zhu Hai link.
This transport link is to reduce passenger and freight transport over land by creating a bridge and tunnel alternative, cutting travel times by a almost 4 hours to a mere 40 minutes.
The cutter unit can be replaced by a dustpan head, which will be used to clean the tunnel track just before the tunnel elements are positioned.

The “Jie Long” has been fitted out by a Constant Tension system on its winches and Damen Navguard software to determine and keep its position perfectly.
Combined with the depth measurement of the suction head, the process is monitored extremely accurate.
The delivery also included other Damen dredging instrumentation, such as vacuum and pressure indication of the dredge pump and flow en density measurement of the dredged mixture.

All equipment was designed and manufactured in the Netherlands, and shipped out to Guangzhou.
There, the Damen Field Service team was ready to do the refit job without delay.
The “Jie Long” has passed its dredging test with flying colours and is now lining up for the big job.

Source: Damen Dredging Equipment, 4 December 2012