CB/T3594-1994 Air pipe head 

The European standard cylindrical air pipe head and disc-shaped breathable cap for ships are mainly through suction and breathing, so that the air pressure in the cabin is close to the atmospheric pressure, so as to keep the pressure within the design pressure of the cabin. In addition, it can prevent seawater, rain and Mars from entering the cabin, and prevent sea wave debris from entering the air permeable pipe into the cabin.

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