Sailor 100, Руководство по установке

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Site preparation
98-136280-B Chapter 3: Installation 3-9
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Mast length and diameter
The placement of the ADU must ensure a rigid structural connection to the hull or
structure of the ship. Parts of the ship with heavy resonant vibrations are not suitable
places for the ADU. A small platform or short mast shall provide rigid support for the
ADU fastening bolts and a rigid interface to the ship.
If it is necessary to use a tall mast, you must stabilise the mast with bracing. Note that
the design values given below depend on rigid ADU-ship interfaces. The cross-
sectional properties and the corresponding maximum free length give a natural
frequency close to 30 Hz. It is recommended to shorten the mast length as much as
possible to obtain higher frequencies. Preferably, mount stays or wires to stabilize the
mast further.
The tables in the next sections give some suggested design values for the free mast
length.
Figure 3-9: Free mast length and bracing for a tall mast
Note Make sure that there is free space below the drain tube. Read
also
Condensation and water intrusion on page 3-15.
Note The tables list the values for steel masts . For aluminium masts ,
the free mast length is reduced to 75% of the values for steel.
Note
Bracing and rigid masts can still not prevent vertical vibration if
the mast is attached to a deck plate that is not rigid. Make every
effort to mount the mast on a surface that is well supported by
ribs. If this is not possible, provide extra deck plate propping.
Free mast length (m)
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