[PSUBS-MAILIST] Fw:

[hank pronk via Personal_Submersibles]

Steve,There is no over pressure valve in the traditional sense.  I will secure the hatch with rubber straps, the same as what holds a Jeep hood down.  If there is an over pressure it will burp out the hatch.  That is the plan for now at least.   When I return from the deep test, I plan to build a test pool also.Hank 


     On Saturday, September 19, 2015 8:01 PM, Stephen Fordyce via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
   

 Hi Hank,
I knew there would be a bunch more behind it:).Is there an over pressure valve though?Cheers,
SteveOn 20/09/2015 7:24 AM, "hank pronk via Personal_Submersibles" <personal_submersibles at psubs.org> wrote:

Hi Steve,I did not mention that the hatch will have two valves to act as a snorkel, in case there is a problem with the bladder and I can not open the hatch at the surface.  I have the same thoughts you mention about the bolts  in some situations, e.g., if I want to get out in a hurry because a leak is developing.  I went this way because it is bullet proof and quick and easy to build.  I do think about it a lot so I may change it to remove the bolts from inside the pod where it is safe.If the sub and pod are at a great overpressure, I can deal with that by pumping air out with my hp compressor, I would just dump the air overboard.  Also it takes very little depth to hold the pod in place with the bolts removed.  At a depth where the pod could fall off, I could just swim out of that scenario.Hank 


     On Saturday, September 19, 2015 3:04 PM, Stephen Fordyce via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
   

 Hi Hank,
That is admirably simple, especially the bit about the pressure holding it on after you undo the bolts.I wonder though did you consider the scenarios of a partly or fully pressurised sub as you are escaping?  (I'm curious as to what valves are included for the escape pod) Highly unlikely really, but then so is having to use the escape pod - here are some specific cases I can think of.
1. There is a slight vacuum in the pod on surfacing (sucking hatch closed)
2. There is a slight overpressure in the pod on surfacing (blowing hatch open)
3. There is a major over-pressure during ascent (ie. Sub and pod were partly or fully at ambient before escape). Main implication is blowing the hatch, but if you were actually at ambient it would be incredibly tragic if the pod fell off due to lack of pressure holding it on.Cheers,
Steve
_______________________________________________
Personal_Submersibles mailing list
Personal_Submersibles at psubs.org
http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles


   
_______________________________________________
Personal_Submersibles mailing list
Personal_Submersibles at psubs.org
http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles



_______________________________________________
Personal_Submersibles mailing list
Personal_Submersibles at psubs.org
http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles


  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20150920/9707941e/attachment.html>