<html><head></head><body><p dir="ltr">There is another option, which may be a touch more expensive, but that is to use air-operated valves for the hydraulic system, which would be mounted outside without an enclosure and handle whatever hydraulic pressure you want to operate at, and then supply this pilot air from (relatively) low pressure solenoid valves inside the pressure boundary. This way, no oil can get inside in the event of failure, every air line can have a shutoff at the pressure boundary, and eg 24 VDC solenoids with small apertures and modest pressure ratings can be used.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On January 21, 2015 5:12:40 PM MST, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<pre class="k9mail"><br />Allan,<br />There are benefits and draw backs as well.  The benefit is having the valve in the oil.  If not then the valve needs an enclosure around the solenoids filled with oil.  It is a pain in the butt. Next is the membrane lid, that eliminates the air bag deal.  So it just depends what your needs and expectations are.  <br />Hank<hr /><br />On Wed, 1/21/15, Alan James via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br /><br /> Subject: Re: [PSUBS-MAILIST] Manipulator arm<br /> To: "Personal Submersibles General Discussion" <personal_submersibles@psubs.org><br /> Received: Wednesday, January 21, 2015, 6:40 PM<br /> <br /> Hank,they also<br /> use water hydraulics on the Remora rov.<a href="http://www.hydra-cell.com/applications/salt-water-pump.html">http://www.hydra-cell.com/applications/salt-water-pump.html</a><br /> I like the<br /> idea of Scott's, of housing the pump & shuttle<br /> valvesin an oil<br /> filled
enclosure with flexible membrane for<br /> equalization;however I<br /> wonder if there is much advantage. You would still have<br /> tohave<br /> through hulls in that enclosure for hydraulic hoses &<br /> electricalpower<br /> & signals. You would end up with more through hulls<br /> &loose the<br /> ability to manually release pressure from the<br /> systemin an<br /> emergency.Alan<br /> <br /> <br />  <br />   <br /> <br />   <br />    From: hank pronk via<br /> Personal_Submersibles<br /> <personal_submersibles@psubs.org><br /> <br /> To: Personal<br /> Submersibles General Discussion<br /> <personal_submersibles@psubs.org> <br /> <br /> Sent:<br /> Thursday, January 22, 2015 12:01 PM<br /> <br /> Subject: Re:<br /> [PSUBS-MAILIST] Manipulator arm<br />  <br />  <br /> <br /> Alan,<br /> When I<br /> had my tour of Nuytco, I saw the arms well actually a shelf<br /> full of them and the valves.  I assumed they were<br /> hydraulic, but maybe not.  It
could work with sea water,<br /> but fresh water could be problematic with freezing.<br /> Hank<hr /><br /> On Wed, 1/21/15, Alan James via<br /> Personal_Submersibles <personal_submersibles@psubs.org><br /> wrote:<br /> <br />  Subject: Re:<br /> [PSUBS-MAILIST] Manipulator arm<br />  To:<br /> "Personal Submersibles General Discussion" <personal_submersibles@psubs.org><br />  Received: Wednesday, January 21, 2015, 2:50<br /> PM<br />  <br />  Not sure,<br />  but don't the "Deep Workers"<br /> have<br />  a hydraulic<br />  system<br /> using sea water, with externalpump &<br /> <br /> valves.Does<br />  anyone know anything about<br /> this?Alan<br />          From:<br />  "swaters@waters-ks.com<br /> via Personal_Submersibles"<br />  <personal_submersibles@psubs.org><br />  <br />  To: Personal<br />  Submersibles General Discussion<br />  <personal_submersibles@psubs.org><br /> <br />  <br />  Sent:<br /> <br /> Thursday, January 22, 2015 4:58
AM<br />  <br /> Subject: Re:<br />  [PSUBS-MAILIST] Manipulator<br /> arm<br />   <br />   <br /> <br /> My plan<br />  was to use O ring seal. I am using<br /> a comoensated<br />  system.Thanks,Scott<br />  Waters<br />  <br />  Sent<br /> from my U.S.<br />  Cellular® Smartphone<br />  <br />  -------- Original message<br />  --------<br />  From: hank pronk<br /> via<br />  Personal_Submersibles  <br />  Date:01/21/2015 <br />  9:41 AM <br /> (GMT-06:00) <br />  To: Personal<br /> <br /> Submersibles General Discussion  <br /> <br /> Subject:<br />  Re: [PSUBS-MAILIST] Manipulator<br /> arm <br />  <br />  <br /> <br /> Scott,<br />  You<br />  need to decide<br /> on what type of hyd system you are going with<br />  before you dive into cylinders.  If you are<br /> going with a<br />  pressure compensated system,<br /> you can use cylinders with a<br />  wiper seals on<br /> the shafts.  If you not pressure<br /> <br /> compensating, then use cylinders with o-ring
seals on the<br />  shafts.  I would use o-ring sealed shafts<br /> regardless.<br /> <br /> Hank<hr /><br />  On Wed, 1/21/15, swaters@waters-ks.com<br /> via<br />  Personal_Submersibles<br /> <br /> <personal_submersibles@psubs.org><br /> wrote:<br />  <br />   Subject: Re:<br /> [PSUBS-MAILIST]<br />  Manipulator arm<br />   To: "Personal<br /> <br /> Submersibles General Discussion"<br /> <br /> <personal_submersibles@psubs.org><br />  <br />  Received: Wednesday, January<br /> 21, 2015, 8:25 AM<br />   <br />  <br /> Gotcha.<br />   I<br />  got about 8<br /> different suppliers I have found so far with<br />   SS cylinders. I think I'll order a few<br /> to<br />  play with. I<br />   am also<br /> planning on using<br />  electric silionoids<br /> for<br />   controlling the<br /> <br /> valves.Thanks,Scott<br />   Waters<br />  <br />  <br />   Sent<br />   from my U.S.<br />  Cellular®<br /> Smartphone<br />   <br />  <br />  -------- Original
message --------<br />   From:<br />  hank pronk via<br /> Personal_Submersibles  <br />  <br /> <br /> Date:01/21/2015  6:54 AM  (GMT-06:00) <br /> <br /> <br />  To: Personal Submersibles General<br /> Discussion  <br />   Subject: Re:<br /> [PSUBS-MAILIST] Manipulator arm<br />  <br />   <br />   <br />  <br />  Scott,<br />   Gamma uses air<br /> cylinders with<br />  hydraulic fluid and<br />   pump.  The hydraulic<br /> <br /> system is very standard except it<br />   uses<br /> air<br />  cylinders in place of hydraulic<br /> cylinders.  <br />  <br /> <br /> Hank<hr /><br />   On Tue, 1/20/15, swaters@waters-ks.com<br /> via<br />   Personal_Submersibles<br />  <br />  <personal_submersibles@psubs.org><br /> wrote:<br />   <br />    Subject:<br /> Re:<br />  [PSUBS-MAILIST] Manipulator arm<br />    To:<br />  "Personal<br /> Submersibles General Discussion"<br />  <br /> <personal_submersibles@psubs.org><br />    Received: Tuesday, January 20,
2015,<br /> 10:27<br />  PM<br />    <br />    <br />    Is Gamma all air<br /> cylinders? Do you just<br />  use<br /> <br />   a air compressor? What happens to the<br /> <br /> air once it is in<br />   the<br /> <br />  <br />  cylinder and you want to lower the<br /> cylinder? Is it<br />    recompressed or somehow<br /> expelled? I really<br />  don't know<br />    crap about pnematics.<br /> <br /> Haha. Why do all the subs use<br />   <br /> hydrolics<br />  and not air. For example<br />   <br />  hydro-lek?Thanks,Scott<br />    Waters<br />    <br />    Sent<br />   <br /> <br /> from my U.S. Cellular® Smartphone<br />    <br />    -------- Original message --------<br />    From: hank pronk via<br /> Personal_Submersibles <br />  <br /> <br />   Date:01/20/2015  9:06 PM  (GMT-06:00)<br /> <br /> <br />    To: Personal Submersibles General<br />  Discussion  <br />    Subject:<br /> Re:<br />  [PSUBS-MAILIST] Manipulator arm <br />    <br />   
<br />   <br /> Scott,<br />    Not sure why you want hydraulic<br /> cylinders. <br />  You want<br />   <br /> air cylinders, they are light<br />  weight and<br /> all<br />   aluminum. <br />    If<br /> you use 2 in bore air cylinders you can<br />  run<br /> on a 500<br />   psi<br />   <br />  system.  Also air cylinders typically have<br /> 5/8 rods<br />   and<br />    that is<br /> the most<br />  important part.  The rod size<br /> is<br />   what<br />    the water<br /> pressure is pushing back against<br />  you<br />   system. <br />    Air<br />  cylinders have a single o ring on the piston<br /> and are<br />    cheap and easy to replace. If<br /> you want ss<br />  rods then just<br /> <br />   replace the chrome rods<br />  when they wear<br /> out.  I made<br />   my<br />    own<br /> rods for Gamma, easy peezy.<br />   <br /> <br /> Hank<hr /><br />    On Tue, 1/20/15, swaters@waters-ks.com<br />  via<br />   <br />
Personal_Submersibles<br />    <personal_submersibles@psubs.org><br />  wrote:<br />    <br />  <br />   Subject: Re:<br />  [PSUBS-MAILIST] Manipulator<br /> arm<br />     To:<br /> <br /> "Personal Submersibles General<br />  <br />  Discussion"<br />   <br />  <personal_submersibles@psubs.org><br />    <br />  Received: Tuesday,<br /> January 20, 2015, 8:52 PM<br />     <br />     Hydrolic.<br />     Also what<br /> size bore does yoursub have<br />    <br /> Hank?Thanks,Scott Waters<br />  <br /> <br />   <br />     Sent<br />     from<br /> my<br />  U.S. Cellular® Smartphone<br />     <br />     -------- Original<br /> message --------<br />     From: hank pronk<br /> via<br />  Personal_Submersibles  <br />    <br />  Date:01/20/2015  7:34<br /> PM  (GMT-06:00) <br />    <br />  To:<br /> Personal Submersibles General Discussion  <br />     Subject: Re: [PSUBS-MAILIST]<br /> Manipulator<br />  arm <br />     <br />    
<br />     Are you using<br /> hydraulic cylinders or air<br />  cylinders.<br />    <br /> <br /> Hank<hr /><br />     On Tue, 1/20/15, swaters@waters-ks.com<br />  via<br />    <br /> Personal_Submersibles<br />     <personal_submersibles@psubs.org><br />  wrote:<br />     <br /> <br />     Subject:<br />  [PSUBS-MAILIST] Manipulator<br /> arm<br />      To:<br /> <br /> "psubs"<br />    <br /> <br /> <personal_submersibles@psubs.org><br />   <br />    Received: Tuesday,<br /> January 20, 2015, 7:51 PM<br />      <br />      Does<br />      anyone have<br /> a reccomendation on a source<br />  for<br />    hydrolic<br />     <br />  cylinders? Ofcourse there are tons online,<br /> just<br />    wondering<br />    <br /> if<br />      someone has a particular place<br /> they like<br />  to get<br />     <br /> them.Thanks,Scott Waters<br />      <br />      Sent<br />      from my U.S.<br /> Cellular®<br />     
Smartphone<br />     <br />  -----Inline Attachment<br /> Follows-----<br />     <br />  <br />     <br /> <br /><hr /><br />      Personal_Submersibles mailing list<br />      Personal_Submersibles@psubs.org<br />     <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 /><hr /><br />     Personal_Submersibles mailing list<br />     Personal_Submersibles@psubs.org<br />    <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<br /> Follows-----<br />     <br />    <br /> <br /><hr /><br />     Personal_Submersibles mailing list<br />     Personal_Submersibles@psubs.org<br />    <br />  <br />  <a
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