HEAVY
DUTY DREDGING CURTAIN
The Dredging Contractor
Sea Curtain System (DCSCS) has been developed to provide
a solution for major dredging contractors where
highly durable but versatile and variable curtains are
required. It is constructed as follows:
 | A float assembly configured from rotationally moulded foam filled
float elements through bolted to a top tension
member configured from reinforced conveyor belting.
The use of this float assembly configuration
provides the following advantages: The rotationally
moulded foam filled floats; have a high resistance
to impact, however, where floats are damaged for
example by water craft trying to cross they can be
replaced individually in situ without the need to
remove a section of curtain and they are UV
resistant and extremely durable and not damaged by
periodic water blasting where marine growth
accumulation needs to be removed. The use of a
conveyor belt top tension member; allows the
integration of extremely high longitudinal tensile
strength without the addition of sewn on webbing etc
for example the standard at 500mm has a longitudinal
strength rating of 2700kN. Whilst 500mm is the
standard depth this may be varied up to 1800mm
overall depth to,
limit
spread of surface or near surface suspended solids,
provide a combined sediment and oil pollution boom
and limit entanglement by surface debris such as
logs or water craft. |
| The DCSCS
skirt system is usually manufactured from woven
high strength PET or PP geo-textiles which is then
manually attached to the belting under the float
line. The detachable curtain provides the following
benefits: the skirts can be easily replaced when
either damaged or entrained
with contaminated material where cleaning is not a
practical option and where a deeper or shallower
curtain is required. The skirts may be removed from
the float assembly allowing a manageable repair
without having to handle the float assembly through
a sewing machine and permits a variation in skirt
depth from project to project without the expense of
replacing the entire float assembly. |
| The DCSCS is
usually ballasted using either heavy
galvanized or stud link chain. Provision is made at
the bottom of the skirt for the ballast to be
shackled to the bottom of the skirt at 500mm
intervals (webbing and grommets) or 1000mm “D”
ring attachment plates. |
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| DCSCS being configured with a 1800mm top belting
assembly and a 1500mm PET 200 skirt for use as a
spreader barge screen for deposition of material
over a pipeline. |
1500mm detachable skirt being installed using latch
lacing method. On completion of lacing lock
stitches are installed periodically to prevent
lacing unraveling if damaged |
Mid mooring plates are attached at the 25m mark on a
50m curtain. In this case as anchoring is to a
barge the d rings face upwards. For normal
anchoring they are inverted. |
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| Skirt is laced into belting for its entire length
ensuring positive containment of plumes |
Large cutter suction dredge Leonardo Da Vinci operating
in close proximity to a DCSCS installation |
DCSCS fitted with 12m PET skirt and moored to piles
using tidal compensating pile collars |
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