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        <div>Alec,  </div><div>I should maybe just put one of the new valves in my pressure chamber with a plug in the low pressure side port and run it up to 4000 feet and see what happens.  I might be over thinking this.</div><div>Hank</div><div><br></div>
        
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                    On Friday, December 21, 2018, 6:56:09 PM MST, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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        <div>Alec,</div><div>Thank you, I am pretty pleased with it.  I am concerned that the water pressure may be too much for the thin SS wall of the cylinder.  There is a very small air space below the piston that would be at atmosphere, as well as the air feed line.  Originally I was thinking about a bleed port and that would solve the problem.  I am not liking that idea.  Then I thought the seal would let water go by but testing shows it won't.</div><div>The solution is a compensator.</div><div>Hank</div><div><br clear="none"></div>
        
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                    On Friday, December 21, 2018, 6:22:22 PM MST, Alec Smyth via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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                <div><div id="yiv8931328418"><div>Now that looks really presentable! But I’m not understanding the issue with the low pressure side. Why would that need protecting, is it not open to the sea?<div><br clear="none"></div><div>Thanks,</div><div>Alec<br clear="none"><div><br clear="none"></div><div><br clear="none"><br clear="none"><div class="yiv8931328418yqt5564302336" id="yiv8931328418yqt56404"><div dir="ltr"><br clear="none">On Dec 21, 2018, at 5:56 PM, 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"><br clear="none"></div><blockquote type="cite"><div dir="ltr"><div class="yiv8931328418ydpf2a8e6eeyahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div></div>
        <div>Hello fellow sub nerds.  After do some total destruction testing of my prototype vent valve - I have decided to replace the plastic top with an aluminum disk.   Also I had to pressurize the air cylinder until it exploded before the piston seal would leak.  I was hoping it had a weaker seal so that the cylinder would be self protecting from water pressure.  The test shows that a compensation system needs to be added to protect the low pressure side of the piston.  No problem - I will mount a second small air cylinder in the air line to act a compensator.  I now have three valves built and ready to install.</div><div>Hank</div><div><br clear="none"></div>
        
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                <div>----- Forwarded Message -----</div>
                <div><b>From:</b> hank pronk <<a rel="nofollow" shape="rect" ymailto="mailto:hanker_20032000@yahoo.ca" target="_blank" href="mailto:hanker_20032000@yahoo.ca">hanker_20032000@yahoo.ca</a>></div><div><b>To:</b> hank pronk <<a rel="nofollow" shape="rect" ymailto="mailto:hanker_20032000@yahoo.ca" target="_blank" href="mailto:hanker_20032000@yahoo.ca">hanker_20032000@yahoo.ca</a>></div><div><b>Sent:</b> Friday, December 21, 2018, 3:49:20 PM MST</div><div><b>Subject:</b> </div><div><br clear="none"></div>
                <div><div dir="ltr"><br clear="none"></div><div dir="ltr"><br clear="none"></div><br clear="none"><br clear="none">Sent from my iPhone</div>
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