[PSUBS-MAILIST] Over Pressure Valve

[John Kammerer via Personal_Submersibles]

Hi Jim:

On the boat if their was an positive pressure while submerged at depth we started the air compressor and charge the air banks. The other option was to raise the snorkel to equalize before opening the hatch.


John K.
(203) 414-1000

Sent from my iPhone

> On Jun 19, 2015, at 3:07 AM, via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
> Jim,
> 
> Thanks for the mental diagram, that helps imensely. Does any one know how the big boys, navy subs, deal with over pressure? Has any one had their OP valve open at depth and if so how much water came in?
> 
> Keith T
> 
> via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
>> Keith,
>> 
>> Sorry, I just got home.  I was hoping Alec and some  others with more 
>> experience than I have would chime in as I see has now  happened.  There have 
>> been some good discussions on OP valves in the  past.  I think some have 
>> installed a T (on its side) inside the sub so  the air enters the horizontal 
>> portion, and any water that comes in  goes down to a small trap or into a tube 
>> that leads to a reservoir.   Others just use a rag to catch the small amount 
>> of water.
>> 
>> Alec, does the OP on the exterior of Snoopy point downward  after it exits 
>> at the top?
>> 
>> We've also discussed having an air pressure gauge or altimeter  set to zero 
>> (1 atm) before diving.  If it indicates any pressure above  that level at 
>> anytime during your dive, you'll know you'll have an over pressure  situation 
>> to deal with as you surface and you'll have an indication of how  severe 
>> that will be.  We've also discussed various things that could cause  an over 
>> pressure condition.
>> 
>> Best regards,
>> Jim
>> 
>> 
>> In a message dated 6/18/2015 7:09:19 P.M. Central Daylight Time,  
>> personal_submersibles at psubs.org writes:
>> 
>> If it opens when submerged, it is because air is on the way out,  and that 
>> prevents water from coming in. Its like blowing through your nose  
>> underwater, your nose is open but if you're blowing, you don't get water in  your 
>> lungs.  
>> 
>> 
>> Certainly you do get a little water in if you push the valve open  manually 
>> while submerged, as a test. Or a few drops if you do so when surfaced  to 
>> equalize, as the valve is all wet. But its nothing much.
>> 
>> 
>> 
>> Best,
>> 
>> Alec
>> 
>> 
>> 
>> On Thu, Jun 18, 2015 at 7:19 PM, Ken Martindale via  Personal_Submersibles 
>> <_personal_submersibles at psubs.org_ (mailto:personal_submersibles at psubs.org) 
>>> wrote:
>> 
>> TEST!!!
>> 
>> -----Original  Message-----
>> From: Personal_Submersibles 
>> [mailto:_personal_submersibles-bounces at psubs.org_ (mailto:personal_submersibles-bounces at psubs.org) ]  On Behalf Of via 
>> Personal_Submersib