<HTML><HEAD></HEAD><BODY><font face="Courier New" size=2>Most time the OPV akts on the surface to equalize the small
pressure difference before you unlock the hatch.<BR>Just to safe your ear drums
on a long term. <BR><BR>On Euronaut we have a normal manual ball vale in
the hatch to do so. <BR></font>You are right on Euronut a overpressure vale will
be a really huge think. <BR>Its not installed for this reason - instead two
large compressors. <BR>But the hatch of Euronaut has heavy hinges and locking
device and can handle some overpressure. <BR><BR>But for 1-3 men sub the OVP is
the much better solution.<BR><BR>"hank pronk via Personal_Submersibles" <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> schrieb:<BR>> <BR>> You have to be experienced to surface slowly and hover while the valve leaks out the air.--------------------------------------------<BR>> On Fri, 6/19/15, Alec Smyth via Personal_Submersibles <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<BR>> <BR>> Subject: Re: [PSUBS-MAILIST] over pressure valve<BR>> To: "Personal Submersibles General Discussion" <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><BR>> Received: Friday, June 19, 2015, 4:16 PM<BR>> <BR>> I<BR>> don't get the "in the hands" part... its<BR>> completely automatic.<BR>> On Fri, Jun 19, 2015 at<BR>> 4:09 PM, hank pronk via Personal_Submersibles <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><BR>> wrote:<BR>> <BR>> <BR>> Agreed,<BR>> <BR>> In the hands of an experienced submarine operator an over<BR>> pressure valve is safe, providing it is large enough. I<BR>> have not seen an example of a large enough OPV. A simple<BR>> valve in the hatch will do the same job, just need an<BR>> umbrella :-)<BR>> <BR>> The noise of a compressor is a welcome sound if it means<BR>> keeping the dome on the sub :-)<BR>> <BR>> Hank--------------------------------------------<BR>> <BR>> On Fri, 6/19/15, Carsten Standfuß" via<BR>> Personal_Submersibles <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><BR>> wrote:<BR>> <BR>> <BR>> <BR>> Subject: Re: [PSUBS-MAILIST] over pressure valve<BR>> <BR>> To: "Personal Submersibles General Discussion"<BR>> <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><BR>> <BR>> Received: Friday, June 19, 2015, 2:47 PM<BR>> <BR>> <BR>> <BR>> But a overpressure vale works<BR>> <BR>> full auto. A compressor<BR>> <BR>>
not. <BR>> <BR>> <BR>> <BR>> A OPV needs<BR>> <BR>> no energy - but a compressor did.<BR>> <BR>> <BR>> <BR>> <BR>> <BR>> A OPV needs no room - but<BR>> <BR>> a compressor did.<BR>> <BR>> <BR>> <BR>> And a<BR>> <BR>> compressor is<BR>> <BR>> a noisy solution..<BR>> <BR>> <BR>> <BR>> vbr<BR>> <BR>> Carsten<BR>> <BR>> <BR>> <BR>> <BR>> <BR>> <BR>> <BR>> "hank<BR>> <BR>> pronk via Personal_Submersibles" <<A href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><BR>> <BR>> schrieb:<BR>> <BR>> > Personally I think an onboard<BR>> <BR>> compressor is a much safer option than an over pressure<BR>> <BR>> valve. There are multiple safety benefits to an<BR>> onboard<BR>> <BR>> compressor, over pressure being the biggy. With a<BR>> <BR>> compressor you can get rid of the pressure without<BR>> surfacing<BR>> <BR>> and trying to control a perfect ascent. With the OPV<BR>> you<BR>> <BR>> have to surface a bit and let air out and wait then<BR>> surface<BR>> <BR>> more and wait and so on. You can't just surface and<BR>> hope<BR>> <BR>> the valve keeps up with the demand. This is more<BR>> important<BR>> <BR>> for subs with large domes.<BR>> <BR>> > The next<BR>> <BR>> benefit to a compressor is, if you lost all your air,<BR>> you<BR>> <BR>> surface by dropping your weight. In my case the weight<BR>> is<BR>> <BR>> small and I would also drop the thruster and tail<BR>> assembly.<BR>> <BR>> Still, not much sub out of the water. With the<BR>> compressor,<BR>> <BR>> I can open my vent valve in the hatch and use the<BR>> compressor<BR>> <BR>> to fill the ballast tanks.<BR>> <BR>> > Hank<BR>> <BR>> ><BR>> <BR>> _______________________________________________<BR>> <BR>> > Personal_Submersibles mailing list<BR>> <BR>> > <A href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><BR>> <BR>> > <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><BR>> <BR>> ><BR>> <BR>> <BR>> <BR>> -----Inline Attachment Follows-----<BR>> <BR>> <BR>> <BR>> _______________________________________________<BR>> <BR>> Personal_Submersibles mailing list<BR>> <BR>> Personal_Submersibles@psubs.org<BR>> <BR>> <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><BR>> <BR>> <BR>> <BR>> <BR>> <BR>> _______________________________________________<BR>> <BR>> Personal_Submersibles mailing list<BR>> <BR>> <A href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><BR>> <BR>> <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><BR>> <BR>> <BR>> <BR>> -----Inline Attachment Follows-----<BR>> <BR>> _______________________________________________<BR>> Personal_Submersibles mailing list<BR>> <A href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><BR>> <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><BR>> <BR>> <BR>> _______________________________________________<BR>> Personal_Submersibles mailing list<BR>> <A href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><BR>> <a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><BR>> <BR><font face="Courier New" size=2> </font></BODY></HTML>