<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div id="yui_3_16_0_1_1442751502541_2861"><span>Steve,</span></div><div id="yui_3_16_0_1_1442751502541_2860" dir="ltr"><span>There is no over pressure valve in the traditional </span>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.</div><div id="yui_3_16_0_1_1442751502541_2860" dir="ltr">Hank</div> <br><div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"> <font size="2" face="Arial"> On Saturday, September 19, 2015 8:01 PM, Stephen Fordyce via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br> </font> </div> <br><br> <div class="y_msg_container"><div id="yiv0017344269"><div><div dir="ltr">Hi Hank,<br clear="none">
I knew there would be a bunch more behind it:).</div>
<div dir="ltr">Is there an over pressure valve though?</div>
<div dir="ltr">Cheers,<br clear="none">
Steve</div>
<div class="yiv0017344269gmail_quote">On 20/09/2015 7:24 AM, "hank pronk via Personal_Submersibles" <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><blockquote class="yiv0017344269gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div class="yiv0017344269yqt8933213976" id="yiv0017344269yqt95673"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div><span>Hi Steve,</span></div><div dir="ltr"><span>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. </span></div><div dir="ltr"><span>I have the </span>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. </div><div dir="ltr">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.</div><div dir="ltr">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. </div><div dir="ltr">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.</div><div dir="ltr">Hank</div> <br clear="none"><div><br clear="none"><br clear="none"></div><div style="display:block;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div dir="ltr"> <font size="2" face="Arial"> On Saturday, September 19, 2015 3:04 PM, Stephen Fordyce via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"> </font> </div> <br clear="none"><br clear="none"> <div><div><div><div dir="ltr">Hi Hank,<br clear="none">
That is admirably simple, especially the bit about the pressure holding it on after you undo the bolts.</div>
<div dir="ltr">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.<br clear="none">
1. There is a slight vacuum in the pod on surfacing (sucking hatch closed)<br clear="none">
2. There is a slight overpressure in the pod on surfacing (blowing hatch open)<br clear="none">
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.</div>
<div dir="ltr">Cheers,<br clear="none">
Steve</div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div> </div> </div> </div></div></div></div><br clear="none">_______________________________________________<br clear="none">
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