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Re: Query re compressed air on submarines
Posted by: ARANTALES ()
Date: October 02, 2017 05:43PM

Dear Sean,

A submarine has flasks with compressed air located in spaces not used by other equipment, and often in free-flooding spaces near stem and stern.

Taken from a design report by the Portsmouth (NH, USA), Naval Shipyard:
A Typ IXC uboat had air flasks aboard having a total capacity of 6200 liters (219 cu.ft.) at 2920 psi.
This was sufficient air to blow all main ballast tanks, fuel ballast and bow and stern buoyancy tanks once at a depth of 180 feet, or 5.65 times the free air volume of these tanks.

A compressor is aboard to refill these tanks once outside-air can be drawn into the boat.

It was possible save bottled air by blowing the tanks just enough for the boat to surface (but ballast tanks not yet fully empty), to start the diesels and then to direct the exhaust from the diesels into the ballast tanks to empty them further.

When the ballast tanks are flooded to dive the boat, the air in the tanks escapes into the free air.

Low pressure air (171 psi, for operating valves, clutches, to blow/drain torpedo tubes, raising masts, pneumatic tools etc.) was derived from the high pressure air through a reducing valve.

Best regards,

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Subject Written By Posted
Query re compressed air on submarines Sean 09/12/2017 05:54PM
Re: Query re compressed air on submarines ARANTALES 10/02/2017 05:43PM
Re: Query re compressed air on submarines Scott Sorenson 10/04/2017 02:20AM

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