|NoiseControl in Ships and Offshore Plattforms by Damping
steel and aluminium constructions used for ships and plattforms are stiff
and therefore highly resonant, no exceptional forces are required to
excite the structure and give rise to noise, which is then transmitted
efficiently. Viscoelastic damping materials, used in properly designed
treatments, can be used to control that noise transmission, by damping the
structure and removing energy from the resonant vibration.
layer forms the filling of a sandwich construction between the steel of
the deck and a latex modified concrete, which at the same time provides
deck levelling. Over 200.000 square meters of Swedac Deck covering systems
have been installed over the past 15 years.
- System V1, V2 and U
System V 1: Viscoelastic sheet VS - 15 glued
to the substrate by means of B-31 contact adhesive and constrained with
SBR - latex concrete. Ideal for small applications where the whole
installation can be finished in one day and in wet areas where high
water resistance is required.
- Swedac SBR-latex
concrete Thickness: 2-2.5 times steel
- Damping layer VS, ACM or
V2: Damping layer ACM, supplied in liquid form and trowelled
out on the deck to a thickness of 2 mm wet layer and constrained with SBR
- latex concrete.
System U 10: Damping
layer DG-U1, 2 component polyurethane, for use on aluminium deck and wet
areas. Applied at 1.5 mm thickness and constrained with SBR - latex
- System U
System U11: Damping layer DG-U 11
constrained with perforated aluminium. Specially developed damping
system for high speed aluminium hulled vessels where low weight and high
damping performance is essential.
||1. 1.5 mm flexible
2. 1-3 mm perforated
3. 1.5 mm Dampling layer
- Floating floor PVP -
SWEDAC PVP floor is produced from 4 mm "sandwich" steel or
aluminium laminated with 50 mm mineral wool (140 - 150 Kg/m3) and
supplied in cassette form, ready to install onboard.
||1. PVP - 2,0 - 2,0
2. 50 mm rockwool, 150
Highly flexible impact noise reducing underlay for parquet and
wooden floors. Supplied as compound which at the samt time levels the
deck. Very low weight, 700 Kg/m3.
10 - 20 mm
Damping Cassettes consist of a U-Profile backbone into which the
viscoelastic material is cast and into which individual fixation legs
are imbedded. Damping Cassettes are very practical and simple to fit by
welding to flat or curved surfaces and are effective on plate
thicknesses from 4 - 50 mm.
VS and compound DG-U6
These are heavy duty
treatments, having a wide range of temperature and frequency
performance. Constructions can be designed for constrained layer
applications on structures such as ships bulkheads, hullsides and decks.
Viscoelastic layers are typically of 1 - 2 mm thickness,
constrained with the same material as the main
structure of around one-quarter of its thickness.
Vibration damped sheet metal
Used for construction of high efficient
floating floors, low noise radiating lining and improved
transmission loss between cabins. Available in steel, stainless steel
Constraining layer and
Ordinary mortars and concrete have a high
compressive strength. However they have a low tensile strength. SWEDAC
SBR-latex can minimise these deficiencies, e.g. in a typical mix of 1
part cement, 3 parts coarse sand and using 5 - 8 % by weight of SWEDAC
SBR-latex, the tensile strength is doubled. A simple practical
demonstration is to paint a slurry of the latex and cement, and a slurry
of water and cement onto steel strips. After hardening it will be found
that only the strip painted with the latex/cement can be bent without
the coating flaking off. This demonstrates the improvement in adhesion
and flexibility given by the latex.
Weather resistant polyurethane compound.
Can be filled with sand up to 60 volume %. The system includes antislip
and UV resistant topcoats.
|Test and Certificates|
|Primary deck covering tested in
accordance with IMO res A.653 (16) and A.687 817). Meets the
requirements of the following authorities. Certificate from the
actual authority is available on request.|
|Swedish Administration of Shipping
||Finnish Board of Shipping|
||USSR Register of Shipping|
|Danish Goverment Ships
||Polish Register of
|Lloyds Register of Shipping
||See - Berufsgenossenschaft
|Department of Transport (UK)
|French Marine Marchande
||NK - Register of Shipping