About the optional gate valve
On some vessels, additional transducer protection is required. One example is vessels working in arctic conditions. It is important for them to prevent ice from damaging the transducer. A gate valve is be added to the hull unit installation. The gate valve is not manufactured by Kongsberg Maritime.
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The gate valve is manufactured by Meson.
•  Gate valve: DN500
•  ManufacturerMeson
•  Manufacturer’s websitehttp://www.mesongroup.com/valves
Technical information about this unit is not included in this SU90 Installation Manual. Refer to the relevant end-user documentation provided by the manufacturer.
The gate valve is placed at the bottom of the transducer dock. It will then increase the total height of the hull unit installation.
•  The hull unit lowers the transducer down to a specified depth below the ship’s hull. These depths are decreased with the physical height of the gate valve. The depths are further decreased with the height of the mounting flange.
•  The SU90 system allows you to define a middle position for the transducer. When defining the middle position, the total height of the gate valve must be taken into consideration.
The installation trunk is not used when a gate valve is mounted. The installation trunk is replaced with a transducer dock.
Note
It is very important that the gate valve mechanisms is interfaced with the hull unit controller. When the gate valve is closed, it must not be possible to lower the transducer. When the transducer is lowered, it must not be possible to close the gate valve.