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Water tight doors

Vertically mounted watertight door 
To allow the passage for personnel water tight doors are fitted , openings must be cut only were essential and they should be as small as possible. 1.4m high, 0.7m wide being the usual. Doors should be of mild steel or cast steel, and they may be arranged to close vertically or horizontally.
The closing action must be positive i.e. it must not rely on gravity. Hinged water tight doors may be allowed in passenger ships and in watertight bulkheads above decks which are placed 2.2m or more above the waterline. Similar doors may be fitted in weather decks openings in cargo ships.

Hinged water tight door

 Hinged water tight doors consist of a heavy section door which when closed seals on a resilient packing mounted in channel bar welded to the door frame.
The door is held firmly in the door frame when closed by the dogging arrangements shown which allow the doors to be opened from either side.Normally six of these dogs are spread equally around the periphery

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