Simrad EQ60 - Manual (Page 197)

Transducer installation
185
857-164342 / Rev.C
Flush mounting in a steel tank
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. 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 interior. If the tube is extended to open air, drainage
must be provided with leakage at the transducer flange or a
separate hole in the tank bottom. Transducer mounting in a steel
tank is shown in the figure below.
Figure 27 Flush mounting of
transducer in steel tank
Transducer
Steel tube for
air outlet
Steel tank
Stuffing tube
Water
Drainage hole
(CD3000)