Table of Contents
Advertisement
Transducer flush mounted in a steel tank
3.
Slamming is the impact of the bottom structure of a ship onto the sea surface. It is mainly observed
while sailing in waves, when the bow raises from the water and subsequently impacts on it. Slamming
induces extremely high loads to ship structures and is taken under consideration when designing ships.
(Wikipedia)
330254/A
Flush mounting is used on very large vessels with a hull so deep
that no air bubbles are found below the hull, and on vessels
operating in shallow harbours or waters, where a protruding
blister can not be accepted.
The standard procedure for flush mounting on a steel vessel is
to weld a steel tank inside the hull, and mount the transducer
into this tank.
Use mounting and clamping rings whenever
provided
Circular transducers may be provided with mounting and
clamping rings, or with drawings to allow for local production
of these. The mounting ring is welded to the hole prepared for
the transducer, while the clamping ring fits around the edge of
the transducer body. Bolts through the clamping ring into the
mounting ring will secure the transducer between them. Note
that several transducers use direction guides to allow correct
mounting.
Smooth surface is important
Mounting screws or bolts must not be extruding from the
transducer or the area immediately around it. Make sure that the
surface of the transducer face, the installation hardware used to
mount it, the hull plating and the putty around the transducer is
as even and smooth as possible. Obstructions on these surfaces
will create problems with turbulent flow.
Use a horizontal support bar on large transducers
We recommend that large transducers are fitted with a horizontal
support bar. The purpose of this support bar is to protect the
transducer from damage in the event of slamming. This happens
if the vessel hull climbs out of the water in heavy seas. The force
of the water when the hull falls down may push the transducer
up and cause damage to its mounting. The support bar can be
secured to the mounting ring using threaded rods.
Water filled
As for a blister, the interior of the tank must be filled with water.
This can be accomplished by air release through a steel tube,
which is extended either to open air 1.5 m above the water line
or to the water outside the hull at a point higher than the tank
How to install the transducer
[3]
19
Advertisement
Table of Contents
