Transducer Tank; Tank Length; For Small Frp Ship - Furuno CH-300 Installation Manual

1.4.3

Transducer tank

Tank length

Shorten the transducer tank so the transducer is lowered into water as deep as
possible. Pay particular attention to the tank length Lt. Determine the length of
the main shaft.
Length of main shaft = Lt + 200 mm (for 400
stroke)
Length of main shaft = Lt + 50 mm (for 250
stroke)
Note: When the retraction tank is constructed
locally, finish it so that welding beads do
not protrude on the inner surface of the
tank. The tank guide will hit the bead,
burning out the raise/lower motor. Also, do
not position the welding bead in the ship's
fore-aft line.

For small FRP ship

The retraction tank should be mounted in
parallel with the ship's draft. For a small ship, however, the hull has 2 degrees of
tilt rising toward the bow. This creates high water pressure in the tank because
of the resistance at the rear of the tank well. To solve this problem, attach a fin to
the hull at the location shown in the figure below.
This fin creates a smooth stream in the retraction dome. Fin specifications:
Height, 1-1.5 cm, Material, FRP.
Retraction tank
Bottom of ship
Fin
1. MOUNTING
Welding bead
Welding bead
1-9