<div dir="ltr">The original Kittredge arrangement is two SCUBA tanks inside the hull, with ball valves allowing you to switch between them. On Snoopy I moved the tanks outside, with independent HP lines into the hull. They had separate hull stops, and from those were combined in a manifold. The HP lines had check valves so that air could only enter the manifold but not back up, so that if for whatever reason (say a blown tank valve O ring) you lost pressure in one of the tanks, its check valve would prevent the manifold and the second tank from emptying. In Shackleton I have reproduced the same exact arrangement except everything but the gauges and BIBS has moved outside. <div><br></div><div>Best,</div><div><br>Alec </div></div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Jan 22, 2016 at 9:09 PM, Alan James via Personal_Submersibles <span dir="ltr"><<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"><div><span>I don't know Brian, maybe Alec could answer that.</span></div><div><span>G. L. have that golden rule that I quoted,</span></div><div><span>Section 2 A.1..."Wherever expedient & feasible, submersibles are to be constructed in such a way</span></div><div dir="ltr"><span>that failure of any single component cannot give rise to a dangerous situation."</span></div><div dir="ltr"><span>   That seems a good rule of thumb to design from.</span></div><div dir="ltr"><span>Cheers Alan</span></div><div dir="ltr"><span><br></span></div><br> <div><br><br></div><div style="display:block">  <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div dir="ltr"> <font size="2" face="Arial"><span class=""> <hr size="1"> <b><span style="font-weight:bold">From:</span></b> Brian Cox via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br> <b><span style="font-weight:bold">To:</span></b> Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> <br> </span><b><span style="font-weight:bold">Sent:</span></b> Saturday, January 23, 2016 2:41 PM<div><div class="h5"><br> <b><span style="font-weight:bold">Subject:</span></b> Re: [PSUBS-MAILIST] Hp valves<br> </div></div></font> </div><div><div class="h5"> <div><br><div><div><div style="font-family:Arial,sans-serif;font-size:10pt"><div>Alan,  Are the Kittridge subs all redundant in that respect?   </div><div> </div><div>Brian<br clear="none"><br clear="none">--- <a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a> wrote:<br clear="none"><br clear="none">From: Alan James via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none">To: Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none">Subject: Re: [PSUBS-MAILIST] Hp valves<br clear="none">Date: Fri, 22 Jan 2016 22:57:07 +0000 (UTC)<br clear="none"><br clear="none"></div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px;background-color:rgb(255,255,255)"><div><span>Brian,</span></div><div><span>just looked up the G.L. rules Section 9 piping systems, pumps & compressors.</span></div><div><span>It says 1.2 Pipes which are led thriught the pressure hull are to be fitted with 2 shut off valves.</span></div><div><span>One of which is to be fitted immediately at the hull wall.</span></div><div><span>    In 3.3 it says " The compressed air supply is to be carried in at least 2 separate banks of receivers with the</span></div><div><span>same total volume."</span></div><div><span>Alan</span></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:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"> <b><span style="font-weight:bold">From:</span></b> Alan James via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold">To:</span></b> Personal Submersibles General Discussion <<a href="mail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r 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:16px"> <div style="font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"> <div dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"> <b><span style="font-weight:bold">From:</span></b> Brian Cox via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold">To:</span></b> Personal Submersibles General Discussion <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold">Sent:</span></b> Saturday, January 23, 2016 6:34 AM<br clear="none"> <b><span style="font-weight:bold">Subject:</span></b> Re: [PSUBS-MAILIST] Hp valves<br clear="none">  </div> <div><br clear="none"><div><div><div style="font-family:Arial,sans-serif;font-size:10pt"><div>ABS says " as close as possible"  I guess I'm ok with a short nipple coming off a elbow.</div><div> </div><div>Brian<br clear="none"><br clear="none">--- <a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a> wrote:<br clear="none"><br clear="none">From: Brian Cox via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none">To: "PSubs " <<a href="mailto:personal_submersibles@psubs.org" target="_blank">personal_submersibles@psubs.org</a>><br clear="none">Subject: [PSUBS-MAILIST] Hp valves<br clear="none">Date: Wed, 20 Jan 2016 08:34:43 -0800<br clear="none"><br clear="none"></div><div><div style="font-family:Arial,sans-serif;font-size:10pt"><div>Is there any distinction as to how close a HP shut off valve or check valve has to be to the hull penetration so as to meet ABS requirements?   Can there be a short nipple between an elbow and the valve for instance?</div><div> </div><div>Brian Cox</div></div></div>
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